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Ritsche P, Franchi MV, Faude O, Finni T, Seynnes O, Cronin NJ. Fully Automated Analysis of Muscle Architecture from B-Mode Ultrasound Images with DL_Track_US. Ultrasound Med Biol 2024; 50:258-267. [PMID: 38007322 DOI: 10.1016/j.ultrasmedbio.2023.10.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/27/2023]
Abstract
OBJECTIVE B-mode ultrasound can be used to image musculoskeletal tissues, but one major bottleneck is analyses of muscle architectural parameters (i.e., muscle thickness, pennation angle and fascicle length), which are most often performed manually. METHODS In this study we trained two different neural networks (classic U-Net and U-Net with VGG16 pre-trained encoder) to detect muscle fascicles and aponeuroses using a set of labeled musculoskeletal ultrasound images. We determined the best-performing model based on intersection over union and loss metrics. We then compared neural network predictions on an unseen test set with those obtained via manual analysis and two existing semi/automated analysis approaches (simple muscle architecture analysis [SMA] and UltraTrack). DL_Track_US detects the locations of the superficial and deep aponeuroses, as well as multiple fascicle fragments per image. RESULTS For single images, DL_Track_US yielded results similar to those produced by a non-trainable automated method (SMA; mean difference in fascicle length: 5.1 mm) and human manual analysis (mean difference: -2.4 mm). Between-method differences in pennation angle were within 1.5°, and mean differences in muscle thickness were less than 1 mm. Similarly, for videos, there was overlap between the results produced with UltraTrack and DL_Track_US, with intraclass correlations ranging between 0.19 and 0.88. CONCLUSION DL_Track_US is fully automated and open source and can estimate fascicle length, pennation angle and muscle thickness from single images or videos, as well as from multiple superficial muscles. We also provide a user interface and all necessary code and training data for custom model development.
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Affiliation(s)
- Paul Ritsche
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland.
| | - Martino V Franchi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Oliver Faude
- Department of Sport, Exercise and Health, University of Basel, Basel, Switzerland
| | - Taija Finni
- Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
| | - Olivier Seynnes
- Department for Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Neil J Cronin
- Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland; School of Sport & Exercise, University of Gloucestershire, Gloucester, UK
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Cronin NJ, Walker J, Tucker CB, Nicholson G, Cooke M, Merlino S, Bissas A. Feasibility of OpenPose markerless motion analysis in a real athletics competition. Front Sports Act Living 2024; 5:1298003. [PMID: 38250008 PMCID: PMC10796501 DOI: 10.3389/fspor.2023.1298003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 12/14/2023] [Indexed: 01/23/2024] Open
Abstract
This study tested the performance of OpenPose on footage collected by two cameras at 200 Hz from a real-life competitive setting by comparing it with manually analyzed data in SIMI motion. The same take-off recording from the men's Long Jump finals at the 2017 World Athletics Championships was used for both approaches (markerless and manual) to reconstruct the 3D coordinates from each of the camera's 2D coordinates. Joint angle and Centre of Mass (COM) variables during the final step and take-off phase of the jump were determined. Coefficients of Multiple Determinations (CMD) for joint angle waveforms showed large variation between athletes with the knee angle values typically being higher (take-off leg: 0.727 ± 0.242; swing leg: 0.729 ± 0.190) than those for hip (take-off leg: 0.388 ± 0.193; swing leg: 0.370 ± 0.227) and ankle angle (take-off leg: 0.247 ± 0.172; swing leg: 0.155 ± 0.228). COM data also showed considerable variation between athletes and parameters, with position (0.600 ± 0.322) and projection angle (0.658 ± 0.273) waveforms generally showing better agreement than COM velocity (0.217 ± 0.241). Agreement for discrete data was generally poor with high random error for joint kinematics and COM parameters at take-off and an average ICC across variables of 0.17. The poor agreement statistics and a range of unrealistic values returned by the pose estimation underline that OpenPose is not suitable for in-competition performance analysis in events such as the long jump, something that manual analysis still achieves with high levels of accuracy and reliability.
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Affiliation(s)
- Neil J. Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
- School of Education and Sciences, University of Gloucestershire, Gloucester, United Kingdom
| | - Josh Walker
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
| | | | - Gareth Nicholson
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
| | - Mark Cooke
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
| | - Stéphane Merlino
- International Relations and Development Department, World Athletics, Monaco, Monaco
| | - Athanassios Bissas
- School of Education and Sciences, University of Gloucestershire, Gloucester, United Kingdom
- Carnegie School of Sport, Leeds Beckett University, Leeds, United Kingdom
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van Dijk K, Khair RM, Sukanen M, Cronin NJ, Finni T. Medial gastrocnemius muscle fascicle function during heel-rise after non-operative repair of Achilles tendon rupture. Clin Biomech (Bristol, Avon) 2023; 105:105977. [PMID: 37156191 DOI: 10.1016/j.clinbiomech.2023.105977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 03/23/2023] [Accepted: 04/27/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND To better understand muscle remodelling in dynamic conditions after an Achilles tendon rupture, this study examined the length of medial gastrocnemius muscle fascicles during a heel-rise at 6- and 12-months after non-operative ATR treatment. METHODS Participants (15 M, 3F) were diagnosed with acute Achilles tendon rupture. Medial gastrocnemius subtendon length, fascicle length and pennation angle were assessed in resting conditions, and fascicle shortening during bi- and unilateral heel-rises. FINDINGS Fascicle shortening was smaller on the injured side (mean difference [95% CI]: -9.7 mm [-14.7 to -4.7 mm]; -11.1 mm [-16.5 to -5.8 mm]) and increased from 6- to 12 months (4.5 mm [2.8-6.3 mm]; 3.2 mm [1.4-4.9 mm]) in bi- and unilateral heel-rise, respectively. The injured tendon was longer compared to contralateral limb (2.16 cm [0.54-3.79 cm]) and the length decreased over time (-0.78 cm [-1.28 to -0.29 cm]). Tendon length correlated with fascicle shortening in bilateral (r = -0.671, p = 0.002; r = -0.666, p = 0.003) and unilateral (r = -0.773, p ≤ 0.001; r = -0.616, p = 0.006) heel-rise, at 6- and 12-months, respectively. In the injured limb, the change over time in fascicle shortening correlated with change in subtendon length in unilateral heel-rise (r = 0.544, p = 0.02). INTERPRETATION This study showed that the lengths of the injured tendon and associated muscle can adapt throughout the first year after rupture when patients continue physiotherapy and physical exercises. For muscle, measures of resting length may not be very informative about adaptations, which manifest themselves during functional tasks such as unilateral heel-rise.
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Affiliation(s)
- Koen van Dijk
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Rautpohjankatu 8, 40700 Jyväskylä, Jyväskylä, Finland
| | - Raad M Khair
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Rautpohjankatu 8, 40700 Jyväskylä, Jyväskylä, Finland
| | - Maria Sukanen
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Rautpohjankatu 8, 40700 Jyväskylä, Jyväskylä, Finland
| | - Neil J Cronin
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Rautpohjankatu 8, 40700 Jyväskylä, Jyväskylä, Finland; School of Sport & Exercise, University of Gloucestershire, Gloucestershire, UK
| | - Taija Finni
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Rautpohjankatu 8, 40700 Jyväskylä, Jyväskylä, Finland.
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Khair RM, Stenroth L, Cronin NJ, Ponkilainen V, Reito A, Finni T. Exploration of muscle-tendon biomechanics one year after Achilles tendon rupture and the compensatory role of flexor hallucis longus. J Biomech 2023; 152:111586. [PMID: 37080080 DOI: 10.1016/j.jbiomech.2023.111586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 03/30/2023] [Accepted: 04/10/2023] [Indexed: 04/22/2023]
Abstract
Achilles tendon (AT) rupture leads to long-term structural and functional impairments. Currently, the predictors of good recovery after rupture are poorly known. Thus, we aimed to explore the interconnections between structural, mechanical, and neuromuscular parameters and their associations with factors that could explain good recovery in patients with non-surgically treated AT rupture. A total of 35 patients with unilateral rupture (6 females) participated in this study. Muscle-tendon structural, mechanical, and neuromuscular parameters were measured 1-year after rupture. Interconnections between the inter-limb differences (Δ) were explored using partial correlations, followed by multivariable linear regression to find associations between the measured factors and the following markers that indicate good recovery: 1) tendon length, 2) tendon non-uniform displacement, and 3) flexor hallucis longus (FHL) normalized EMG amplitude difference between limbs. Δmedial gastrocnemius (MG) (β = -0.12, p = 0.007) and Δlateral gastrocnemius (β = -0.086, p = 0.030) subtendon lengths were associated with MG tendon Δstiffness. MG (β = 11.56, p = 0.003) and soleus (β = 2.18, p = 0.040) Δsubtendon lengths explained 48 % of variance in FHL EMG amplitude. Regression models for tendon length and non-uniform displacement were not significant. Smaller inter-limb differences in Achilles subtendon lengths were associated with smaller differences in the AT stiffness between limbs, and a smaller contribution of FHL muscle to the plantarflexion torque. In the injured limb, the increased contribution of FHL appears to partially counteract a smaller contribution from MG due to the elongated tendon, however the role of FHL should not be emphasized during rehabilitation to allow recovery of the TS muscles.
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Affiliation(s)
- Ra'ad M Khair
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland.
| | - Lauri Stenroth
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Neil J Cronin
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland; School of Sport and Exercise, University of Gloucestershire, UK
| | | | - Aleksi Reito
- Central Finland Central Hospital Nova, Jyväskylä, Finland
| | - Taija Finni
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
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Mayfield DL, Cronin NJ, Lichtwark GA. Understanding altered contractile properties in advanced age: insights from a systematic muscle modelling approach. Biomech Model Mechanobiol 2023; 22:309-337. [PMID: 36335506 PMCID: PMC9958200 DOI: 10.1007/s10237-022-01651-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 10/14/2022] [Indexed: 11/09/2022]
Abstract
Age-related alterations of skeletal muscle are numerous and present inconsistently, and the effect of their interaction on contractile performance can be nonintuitive. Hill-type muscle models predict muscle force according to well-characterised contractile phenomena. Coupled with simple, yet reasonably realistic activation dynamics, such models consist of parameters that are meaningfully linked to fundamental aspects of muscle excitation and contraction. We aimed to illustrate the utility of a muscle model for elucidating relevant mechanisms and predicting changes in output by simulating the individual and combined effects on isometric force of several known ageing-related adaptations. Simulating literature-informed reductions in free Ca2+ concentration and Ca2+ sensitivity generated predictions at odds qualitatively with the characteristic slowing of contraction speed. Conversely, incorporating slower Ca2+ removal or a fractional increase in type I fibre area emulated expected changes; the former was required to simulate slowing of the twitch measured experimentally. Slower Ca2+ removal more than compensated for force loss arising from a large reduction in Ca2+ sensitivity or moderate reduction in Ca2+ release, producing realistic age-related shifts in the force-frequency relationship. Consistent with empirical data, reductions in free Ca2+ concentration and Ca2+ sensitivity reduced maximum tetanic force only slightly, even when acting in concert, suggesting a modest contribution to lower specific force. Lower tendon stiffness and slower intrinsic shortening speed slowed and prolonged force development in a compliance-dependent manner without affecting force decay. This work demonstrates the advantages of muscle modelling for exploring sources of variation and identifying mechanisms underpinning the altered contractile properties of aged muscle.
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Affiliation(s)
- Dean L Mayfield
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, USA.
| | - Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
- School of Sport and Exercise, University of Gloucestershire, Cheltenham, UK
| | - Glen A Lichtwark
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
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Cronin NJ, Mansoubi M, Hannink E, Waller B, Dawes H. Accuracy of a computer vision system for estimating biomechanical measures of body function in axial spondyloarthropathy patients and healthy subjects. Clin Rehabil 2023:2692155221150133. [PMID: 36638533 DOI: 10.1177/02692155221150133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE Advances in computer vision make it possible to combine low-cost cameras with algorithms, enabling biomechanical measures of body function and rehabilitation programs to be performed anywhere. We evaluated a computer vision system's accuracy and concurrent validity for estimating clinically relevant biomechanical measures. DESIGN Cross-sectional study. SETTING Laboratory. PARTICIPANTS Thirty-one healthy participants and 31 patients with axial spondyloarthropathy. INTERVENTION A series of clinical functional tests (including the gold standard Bath Ankylosing Spondylitis Metrology Index tests). Each test was performed twice: the first performance was recorded with a camera, and a computer vision algorithm was used to estimate variables. During the second performance, a clinician measured the same variables manually. MAIN MEASURES Joint angles and inter-limb distances. Clinician measures were compared with computer vision estimates. RESULTS For all tests, clinician and computer vision estimates were correlated (r2 values: 0.360-0.768). There were no significant mean differences between methods for shoulder flexion (left: 2 ± 14° (mean ± standard deviation), t = 0.99, p < 0.33; right: 3 ± 15°, t = 1.57, p < 0.12), side flexion (left: - 0.5 ± 3.1 cm, t = -1.34, p = 0.19; right: 0.5 ± 3.4 cm, t = 1.05, p = 0.30) and lumbar flexion ( - 1.1 ± 8.2 cm, t = -1.05, p = 0.30). For all other movements, significant differences were observed, but could be corrected using a systematic offset. CONCLUSION We present a computer vision approach that estimates distances and angles from clinical movements recorded with a phone or webcam. In the future, this approach could be used to monitor functional capacity and support physical therapy management remotely.
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Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland.,School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
| | - Maedeh Mansoubi
- Intersect@Exeter, Medical School, 171002University of Exeter, Exeter, UK.,Biomedical Research Center, Medical School, Faculty of Health and Life sciences, 6397University of Exeter, Exeter, UK
| | - Erin Hannink
- Centre for Movement, Occupational and Rehabilitation Science (MOReS), 6395Oxford Brookes University, Oxford, UK
| | - Benjamin Waller
- Physical Activity, Physical Education, Sport and Health Research Centre (PAPESH), Sports Science Department, School of Science and Engineering, 64401Reykjavik University, Reykjavik, Iceland.,Good Boost Wellbeing limited, London, UK
| | - Helen Dawes
- Intersect@Exeter, Medical School, 171002University of Exeter, Exeter, UK.,Centre for Movement, Occupational and Rehabilitation Science (MOReS), 6395Oxford Brookes University, Oxford, UK.,Oxford Health, Biomedical Research Centre, University of Oxford, Oxford, UK
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Ritsche P, Wirth P, Cronin NJ, Sarto F, Narici MV, Faude O, Franchi MV. DeepACSA: Automatic Segmentation of Cross-Sectional Area in Ultrasound Images of Lower Limb Muscles Using Deep Learning. Med Sci Sports Exerc 2022; 54:2188-2195. [PMID: 35941517 DOI: 10.1249/mss.0000000000003010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Muscle anatomical cross-sectional area (ACSA) can be assessed using ultrasound and images are usually evaluated manually. Here, we present DeepACSA, a deep learning approach to automatically segment ACSA in panoramic ultrasound images of the human rectus femoris (RF), vastus lateralis (VL), gastrocnemius medialis (GM) and lateralis (GL) muscles. METHODS We trained three muscle-specific convolutional neural networks (CNN) using 1772 ultrasound images from 153 participants (age = 38.2 yr, range = 13-78). Images were acquired in 10% increments from 30% to 70% of femur length for RF and VL and at 30% and 50% of muscle length for GM and GL. During training, CNN performance was evaluated using intersection-over-union scores. We compared the performance of DeepACSA to manual analysis and a semiautomated algorithm using an unseen test set. RESULTS Comparing DeepACSA analysis of the RF to manual analysis with erroneous predictions removed (3.3%) resulted in intraclass correlation (ICC) of 0.989 (95% confidence interval = 0.983-0.992), mean difference of 0.20 cm 2 (0.10-0.30), and SEM of 0.33 cm 2 (0.26-0.41). For the VL, ICC was 0.97 (0.96-0.968), mean difference was 0.85 cm 2 (-0.4 to 1.31), and SEM was 0.92 cm 2 (0.73-1.09) after removal of erroneous predictions (7.7%). After removal of erroneous predictions (12.3%), GM/GL muscles demonstrated an ICC of 0.98 (0.96-0.99), a mean difference of 0.43 cm 2 (0.21-0.65), and an SEM of 0.41 cm 2 (0.29-0.51). Analysis duration was 4.0 ± 0.43 s (mean ± SD) for analysis of one image in our test set using DeepACSA. CONCLUSIONS DeepACSA provides fast and objective segmentation of lower limb panoramic ultrasound images comparable with manual segmentation. Inaccurate model predictions occurred predominantly on low-quality images, highlighting the importance of high-quality image for accurate prediction.
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Affiliation(s)
- Paul Ritsche
- Department of Sport, Exercise and Health, University of Basel, Basel, SWITZERLAND
| | | | - Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, FINLAND
| | - Fabio Sarto
- Department of Biomedical Sciences, University of Padova, Padova, ITALY
| | | | - Oliver Faude
- Department of Sport, Exercise and Health, University of Basel, Basel, SWITZERLAND
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Khair RM, Stenroth L, Cronin NJ, Reito A, Paloneva J, Finni T. In vivo localised gastrocnemius subtendon representation within the healthy and ruptured human Achilles tendon. J Appl Physiol (1985) 2022; 133:11-19. [PMID: 35546126 DOI: 10.1152/japplphysiol.00084.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Achilles tendon (AT) is composed of three distinct in-series elastic subtendons, arising from different muscles in the triceps surae. Independent activation of any of these muscles is thought to induce sliding between the adjacent AT subtendons. We aimed to investigate displacement patterns during voluntary contraction (VOL) and selective transcutaneous stimulation of medial (MGstim) and lateral (LGstim) gastrocnemius between ruptured and healthy tendons, and to examine the representative areas of AT subtendons. Twenty-eight patients with unilateral AT rupture performed bilateral VOL at 30% of the maximal isometric un-injured plantarflexion torque. AT displacement was analysed from sagittal B-mode ultrasonography images during VOL, MGstim and LGstim. Three-way ANOVA revealed a significant two-way interaction of contraction type*location on the tendon displacement (F(10-815)=3.72, p<0.001). The subsequent two-way analysis revealed a significant contraction type*location interaction for tendon displacement (F(10-410)=3.79, p<0.001) in the un-injured limb only, where LGstim displacement pattern was significantly different from MGstim (p=0.008) and VOL (p=0.005). When comparing contraction types between limbs the there were no difference in the displacement patterns, but displacement amplitudes differed. There was no significant difference in the location of maximum or minimum displacement between limbs. The displacement pattern was not different in non-surgically treated compared to un-injured tendons one-year post rupture. Our results suggest that near the calcaneus, LG subtendon is located in the most anterior region adjacent to medial gastrocnemius. However, free tendon stiffness seems to be lower in the injured AT, leading to more displacement during electrically-induced contractions compared to the un-injured.
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Affiliation(s)
- Raad M Khair
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
| | - Lauri Stenroth
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Neil J Cronin
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland.,School of Sport and Exercise, University of Gloucestershire, United Kingdom
| | - Aleksi Reito
- Central Finland Health Care District, Finland and University of Eastern Finland, Finland
| | - Juha Paloneva
- Central Finland Health Care District, Finland and University of Eastern Finland, Finland
| | - Taija Finni
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
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Abstract
PURPOSE Measurement of medial gastrocnemius (MG) tendon length using ultrasonography (US) requires the muscle-tendon junction (MTJ) to be located. Previously, the MG MTJ has been tracked from different proximo-distal locations near the MTJ, which could influence estimates of tendon length change due to the different characteristics of the aponeurosis and tendon. We used US to evaluate the effect of tracking point location on MG MTJ displacement during maximal and submaximal (10, 20 and 30% of the non-injured maximal) isometric plantar flexion contractions. METHODS Displacement behaviour of MTJ was tracked from (1) the exact MTJ; and (2) from an insertion point of a muscle fascicle on the aponeurosis 1.3 ± 0.6 cm proximal to the MTJ, in both limbs of patients with unilateral Achilles tendon rupture (ATR) (n = 22, 4 females, 42 ± 9 years, 177 ± 9 cm, 79 ± 10 kg). RESULTS In the non-injured limb, displacement (1.3 ± 0.5 cm vs. 1.1 ± 0.6 cm) and strain (6.7 ± 2.8% vs. 5.8 ± 3.3%) during maximal voluntary contraction were larger when tracking a point on the aponeurosis than when tracking the MTJ (both p < 0.001). The same was true for all contraction levels, and both limbs. CONCLUSION Tracking a point on the aponeurosis consistently exaggerates estimates of tendon displacement, and the magnitude of this effect is contraction intensity-dependent. When quantifying displacement and strain of the Achilles tendon, the MTJ should be tracked directly, rather than tracking a surrogate point proximal to the MTJ. The latter method includes part of the aponeurosis, which due to its relative compliance, artificially increases estimates of MTJ displacement and strain.
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Affiliation(s)
- Taija Finni
- Faculty of Sport and Health Sciences, Neuromuscular Research Centre, University of Jyväskylä, Viveca 227, Rautpohjankatu 8, 40700, Jyväskylä, Finland.
| | - Annamaria Peter
- Faculty of Sport and Health Sciences, Neuromuscular Research Centre, University of Jyväskylä, Viveca 227, Rautpohjankatu 8, 40700, Jyväskylä, Finland
| | - Ra'ad Khair
- Faculty of Sport and Health Sciences, Neuromuscular Research Centre, University of Jyväskylä, Viveca 227, Rautpohjankatu 8, 40700, Jyväskylä, Finland
| | - Neil J Cronin
- Faculty of Sport and Health Sciences, Neuromuscular Research Centre, University of Jyväskylä, Viveca 227, Rautpohjankatu 8, 40700, Jyväskylä, Finland.,School of Sport & Exercise, University of Gloucestershire, Gloucester, UK
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Khair RM, Stenroth L, Cronin NJ, Reito A, Paloneva J, Finni T. Muscle-tendon morphomechanical properties of non-surgically treated Achilles tendon 1-year post-rupture. Clin Biomech (Bristol, Avon) 2022; 92:105568. [PMID: 35066440 DOI: 10.1016/j.clinbiomech.2021.105568] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 10/12/2021] [Accepted: 12/30/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Achilles tendon rupture appears to alter stiffness and length of the tendon. These alterations may affect the function of tendon in force transmission and in energy storage and recovery. We studied the mechanical properties of the Achilles' tendon post-rupture and their association with function. METHODS Twenty-four (20 males, 4 females) participants (mean age: 43 y, 176 cm, 81 kg) were recruited. Ultrasonography and dynamometry were used to assess the muscle-tendon unit morphological and mechanical properties of non-surgically treated patients 1-year post rupture. FINDINGS Injured tendons were longer with difference of 1.8 cm (95%CI: 0.5-1.9 cm; P < 0.001), and thicker by 0.2 mm (0.2-0.3 mm; P < 0.01). Medial gastrocnemius cross-sectional area was 1.0 cm2 smaller (0.8-1.1 cm2; P < 0.001), fascicles were 0.6 cm shorter (0.5-0.7 cm; P < 0.001) and pennation angle was 2.5° higher (1.3-3.6°; P < 0.001) when compared to the uninjured limb. We found no differences between injured and uninjured tendon stiffness 1-year post-rupture (mean difference: 29.8 N/mm, -7.7-67.3 N/mm; P = 0.170). The injured tendon showed 1.8 mm (1.2-2.4 mm; P < 0.01) lower elongation during maximal voluntary isometric contractions. Patient-reported functional outcome was related to the tendon resting length (β = 0.68, r(10) = 4.079, P = 0.002). Inter-limb differences in the medial gastrocnemius fascicle length were related to inter-limb differences in maximum contractions (β = 1.17, r(14) = 2.808, P = 0.014). INTERPRETATION Longer Achilles tendon resting length was associated with poorer self-evaluated functional outcome. Although the stiffness of non-surgically treated and uninjured tendons was similar 1-year post rupture, plantar flexion strength deficit was still present, possibly due to shorter medial gastrocnemius fascicle length.
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Affiliation(s)
- Ra'ad M Khair
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland.
| | - Lauri Stenroth
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Neil J Cronin
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland; School of Sport & Exercise, University of Gloucestershire, UK
| | | | - Juha Paloneva
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Central Finland Health Care District, Finland
| | - Taija Finni
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
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11
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Walker J, Bissas A, Wainwright B, Hanley B, Cronin NJ. Repeatability and sensitivity of passive mechanical stiffness measurements in the triceps surae muscle-tendon complex. Scand J Med Sci Sports 2021; 32:83-93. [PMID: 34606650 DOI: 10.1111/sms.14070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 09/16/2021] [Accepted: 10/01/2021] [Indexed: 01/03/2023]
Abstract
Measurements of muscle-tendon unit passive mechanical properties are often used to illustrate acute and chronic responses to a training stimulus. The purpose of this study was to quantify the inter-session repeatability of triceps surae passive stiffness measurements in athletic and non-athletic populations, with the view to discussing its usefulness both as a muscle-tendon profiling tool and a control measure for studies with multiple data collection sessions. The study also aimed to observe the effects of quiet standing on passive stiffness parameters. Twenty-nine men (10 cyclists, nine triathletes, 10 controls) visited the laboratory on three separate occasions, where passive stiffness tests were carried out using an isokinetic dynamometer and B-mode ultrasound. Participants were fully rested on two of the sessions and subjected to 20 min of quiet standing in the other. The passive stiffness assessment generally showed only moderate inter-session repeatability but was still able to detect inter-group differences, with triathletes showing higher passive stiffness than cyclists (p < 0.05). Furthermore, quiet standing impacted passive stiffness by causing a reduction in ankle joint range of motion, although mechanical resistance to stretch in the muscle-tendon unit at a given joint angle was relatively unaffected. These findings show that passive stiffness assessment is appropriate for detecting inter-group differences in the triceps surae and even the effects of a low-intensity task such as quiet standing, despite showing some inter-session variation. However, the inter-session variation suggests that passive stiffness testing might not be suitable as a control measure when testing participants on multiple sessions.
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Affiliation(s)
- Josh Walker
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Athanassios Bissas
- School of Sport and Exercise, University of Gloucestershire, Cheltenham, UK
| | | | - Brian Hanley
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Neil J Cronin
- School of Sport and Exercise, University of Gloucestershire, Cheltenham, UK.,Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
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12
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Hegyi A, Csala D, Kovács B, Péter A, Liew BXW, Yue Y, Finni T, Tihanyi J, Cronin NJ. Superimposing hip extension on knee flexion evokes higher activation in biceps femoris than knee flexion alone. J Electromyogr Kinesiol 2021; 58:102541. [PMID: 33706051 DOI: 10.1016/j.jelekin.2021.102541] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/24/2021] [Accepted: 03/01/2021] [Indexed: 01/12/2023] Open
Abstract
Hamstring muscle function during knee flexion has been linked to hamstring injury and performance. However, it is unclear whether knee flexion alone (KF) requires similar hamstring electromyography (EMG) activity pattern to simultaneous hip extension and knee flexion (HE-KF), a combination that occurs in the late swing phase of sprinting. This study examined whether HE-KF maximal voluntary isometric contraction (MVIC) evokes higher (EMG) activity in biceps femoris long head (BFlh) and semitendinosus (ST) than KF alone. Effects of shank rotation angles were also tested. Twenty-one males performed the above-mentioned MVICs while EMG activity was measured along ST and BFlh. Conditions were compared using a one-way mixed functional ANOVA model under a fully Bayesian framework. Higher EMG activity was found in HE-KF in all shank rotation positions than in KF in the middle region of BFlh (highest in the 9th channel, by 0.022 mV [95%CrI 0.014 to 0.030] in neutral shank position). For ST, this was only observed in the neutral shank position and in the most proximal channel (by 0.013 mV [95%CrI 0.001 to 0.025]). We observed muscle- and region-specific responses to HE-KF. Future studies should examine whether hamstring activation in this task is related to injury risk and sprint performance.
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Affiliation(s)
- A Hegyi
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Finland; Laboratory "Movement, Interactions, Performance", Faculty of Sport Sciences, University of Nantes, France.
| | - D Csala
- Department of Kinesiology, University of Physical Education, Budapest, Hungary
| | - B Kovács
- Department of Kinesiology, University of Physical Education, Budapest, Hungary
| | - A Péter
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Finland
| | - B X W Liew
- School of Sport, Rehabilitation and Exercise Sciences, University of Essex, Colchester, Essex CO4 3SQ, United Kingdom
| | - Y Yue
- Paul H. Chook Department of Information Systems and Statistics, Zicklin School of Business, Baruch College, The City University of New York, United States
| | - T Finni
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Finland
| | - J Tihanyi
- Department of Kinesiology, University of Physical Education, Budapest, Hungary
| | - N J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Finland; School of Sport and Exercise, University of Gloucestershire, UK
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13
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M Khair R, Stenroth L, Péter A, Cronin NJ, Reito A, Paloneva J, Finni T. Non-uniform displacement within ruptured Achilles tendon during isometric contraction. Scand J Med Sci Sports 2021; 31:1069-1077. [PMID: 33464638 DOI: 10.1111/sms.13925] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 01/21/2023]
Abstract
The purpose of this study was investigate tendon displacement patterns in non-surgically treated patients 14 months after acute Achilles tendon rupture (ATR) and to classify patients into groups based on their Achilles tendon (AT) displacement patterns. Twenty patients were tested. Sagittal images of AT were acquired using B-mode ultrasonography during ramp contractions at a torque level corresponding to 30% of the maximal isometric plantarflexion torque of the uninjured limb. A speckle tracking algorithm was used to track proximal-distal movement of the tendon tissue at 6 antero-posterior locations. Two-way repeated measures ANOVA for peak tendon displacement was performed. K-means clustering was used to classify patients according to AT displacement patterns. The difference in peak relative displacement across locations was larger in the uninjured (1.29 ± 0.87 mm) than the injured limb (0.69 ± 0.68 mm), with a mean difference (95% CI) of 0.60 mm (0.14-1.05 mm, P < .001) between limbs. For the uninjured limb, cluster analysis formed 3 groups, while 2 groups were formed for the injured limb. The three distinct patterns of AT displacement during isometric plantarflexion in the uninjured limb may arise from subject-specific anatomical variations of AT sub-tendons, while the two patterns in the injured limb may reflect differential recovery after ATR with non-surgical treatment. Subject-specific tendon characteristics are a vital determinant of stress distribution across the tendon. Changes in stress distribution may lead to variation in the location and magnitude of peak displacement within the free AT. Quantifying internal tendon displacement patterns after ATR provides new insights into AT recovery.
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Affiliation(s)
- Ra'ad M Khair
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
| | - Lauri Stenroth
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Annamária Péter
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
| | - Neil J Cronin
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland.,Department for Health, University of Bath, Bath, UK
| | - Aleksi Reito
- Central Finland Health Care District, Jyväskylä, Finland
| | - Juha Paloneva
- Central Finland Health Care District, Jyväskylä, Finland
| | - Taija Finni
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
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14
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Cronin NJ, Finni T, Seynnes O. Using deep learning to generate synthetic B-mode musculoskeletal ultrasound images. Comput Methods Programs Biomed 2020; 196:105583. [PMID: 32544777 DOI: 10.1016/j.cmpb.2020.105583] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND OBJECTIVE Deep learning approaches are common in image processing, but often rely on supervised learning, which requires a large volume of training images, usually accompanied by hand-crafted labels. As labelled data are often not available, it would be desirable to develop methods that allow such data to be compiled automatically. In this study, we used a Generative Adversarial Network (GAN) to generate realistic B-mode musculoskeletal ultrasound images, and tested the suitability of two automated labelling approaches. METHODS We used a model including two GANs each trained to transfer an image from one domain to another. The two inputs were a set of 100 longitudinal images of the gastrocnemius medialis muscle, and a set of 100 synthetic segmented masks that featured two aponeuroses and a random number of 'fascicles'. The model output a set of synthetic ultrasound images and an automated segmentation of each real input image. This automated segmentation process was one of the two approaches we assessed. The second approach involved synthesising ultrasound images and then feeding these images into an ImageJ/Fiji-based automated algorithm, to determine whether it could detect the aponeuroses and muscle fascicles. RESULTS Histogram distributions were similar between real and synthetic images, but synthetic images displayed less variation between samples and a narrower range. Mean entropy values were statistically similar (real: 6.97, synthetic: 7.03; p = 0.218), but the range was much narrower for synthetic images (6.91 - 7.11 versus 6.30 - 7.62). When comparing GAN-derived and manually labelled segmentations, intersection-over-union values- denoting the degree of overlap between aponeurosis labels- varied between 0.0280 - 0.612 (mean ± SD: 0.312 ± 0.159), and pennation angles were higher for the GAN-derived segmentations (25.1° vs. 19.3°; p < 0.001). For the second segmentation approach, the algorithm generally performed equally well on synthetic and real images, yielding pennation angles within the physiological range (13.8-20°). CONCLUSIONS We used a GAN to generate realistic B-mode ultrasound images, and extracted muscle architectural parameters from these images automatically. This approach could enable generation of large labelled datasets for image segmentation tasks, and may also be useful for data sharing. Automatic generation and labelling of ultrasound images minimises user input and overcomes several limitations associated with manual analysis.
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Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyvaskyla, Finland; Department for Health, Bath University, UK; School of Sport & Exercise, University of Gloucestershire, Gloucestershire, UK.
| | - Taija Finni
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyvaskyla, Finland
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15
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Gao Y, Cronin NJ, Nevala N, Finni T. Validity of long-term and short-term recall of occupational sitting time in Finnish and Chinese office workers. J Sport Health Sci 2020; 9:345-351. [PMID: 32768127 PMCID: PMC7411120 DOI: 10.1016/j.jshs.2017.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 11/10/2016] [Accepted: 05/15/2017] [Indexed: 06/11/2023]
Abstract
BACKGROUND As sedentary behavior is a global health issue, there is a need for methods of self-reported sitting assessment. The accuracy and reliability of these methods should also be tested in various populations and different cultural contexts. This study examined the validity of long-term and short-term recall of occupational sitting time in Finnish and Chinese subgroups. METHODS Two cohort groups of office-based workers (58.6% female, age range 22-67 years) participated: a Finnish group (FIN, n = 34) and a Chinese group (CHI, n = 36). Long-term (past 3-month sitting) and short-term (daily sitting assessed on 5 consecutive days) single-item measures were used to assess self-reported occupational sitting time. Values from each participant were compared to objectively measured occupational sitting time assessed via thigh-mounted accelerometers, with Spearman's rho (ρ) used to assess validity and the Bland-Altman method used to evaluate agreement. Coefficients of variation depicted day-to-day variability of time spent on sitting at work. RESULTS In the total study sample, the results showed that both long-term and short-term recall correlated with accelerometer-derived sitting time (ρ = 0.532, 95% confidence intervals (CI): 0.336-0.684, p< 0.001; ρ = 0.533, 95%CI: 0.449-0.607, p< 0.001, respectively). Compared to objectively measured sitting time, self-reported occupational sitting time was 2.4% (95%CI: -0.5% to 5.3%, p = 0.091) and 2.2% (95%CI: 0.7%-3.6%, p = 0.005) greater for long-term and short-term recall, respectively. The agreement level was within the range -21.2% to 25.9% for long-term recall, and -24.2% to 28.5% for short-term recall. During a 5-day work week, day-to-day variation of sitting time was 9.4% ± 11.4% according to short-term recall and 10.4% ± 8.4% according to accelerometry-derived occupational sitting time. CONCLUSION Overall, both long-term and short-term self-reported instruments provide acceptable measures of occupational sitting time in an office-based workplace, but their utility at the individual level is limited due to large variability.
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Affiliation(s)
- Ying Gao
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä FI-40014, Finland.
| | - Neil J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä FI-40014, Finland
| | - Nina Nevala
- Finnish Institute of Occupational Health, Helsinki FI-00250, Finland
| | - Taija Finni
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä FI-40014, Finland
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16
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Abstract
INTRODUCTION Hamstring strain injuries typically occur in the proximal biceps femoris long head (BFlh) at high running speeds. Strain magnitude seems to be the primary determinant of strain injury, and may be regulated by muscle activation. In running, BFlh strain is largest in the proximal region, especially at high speeds. However, region-specific activity has not been examined. This study examined the proximal-distal and intermuscular activity of BFlh and semitendinosus (ST) as a function of increasing running speed. METHODS Thirteen participants ran at steady speeds of 4.1 (slow), 5.4 (moderate), and 6.8 m·s (fast) on a treadmill. Region- and muscle-specific EMG activity were recorded at each speed using high-density EMG, and were normalized to maximal voluntary isometric activity. Muscle-tendon unit lengths were calculated from kinematic recordings. Speed effects, regional, and intermuscular differences were tested with Statistical Parametric Mapping. RESULTS With increasing running speed, EMG activity increased in all regions of both muscles to a similar extent in the clinically relevant late swing phase. Increases in muscle-tendon unit lengths in late swing as a function of running speed were comparatively small. In fast running, EMG activity was highest in late swing in all regions, and reached 115% ± 20% (proximal region, mean ± 95% confidence limit), 106% ± 11% (middle), and 124% ± 16% (distal) relative to maximal voluntary isometric activity in BFlh. Regional and intermuscular EMG patterns were highly individual, but each individual maintained similar proximal-distal and intermuscular EMG activity patterns across running speeds. CONCLUSIONS Running is associated with highly individual hamstring activity patterns, but these patterns are similar across speeds. It may thus be crucial to implement running at submaximal speeds early after hamstring injury for restoration of normal neuromuscular function.
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Affiliation(s)
- András Hegyi
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, FINLAND
| | - Basílio A M Gonçalves
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, FINLAND.,School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, AUSTRALIA
| | - Taija Finni
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, FINLAND
| | - Neil J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, FINLAND
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17
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Bissas A, Havenetidis K, Walker J, Hanley B, Nicholson G, Metaxas T, Christoulas K, Cronin NJ. Muscle-tendon morphology and function following long-term exposure to repeated and strenuous mechanical loading. Scand J Med Sci Sports 2020; 30:1151-1162. [PMID: 32246562 DOI: 10.1111/sms.13669] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/16/2020] [Accepted: 03/13/2020] [Indexed: 01/12/2023]
Abstract
We mapped structural and functional characteristics of muscle-tendon units in a population exposed to very long-term routine overloading. Twenty-eight military academy cadets (age = 21.00 ± 1.1 years; height = 176.1 ± 4.8 cm; mass = 73.8 ± 7.0 kg) exposed for over 24 months to repetitive overloading were profiled via ultrasonography with a senior subgroup of them (n = 11; age = 21.4 ± 1.0 years; height = 176.5 ± 4.8 cm; mass = 71.4 ± 6.6 kg) also tested while walking and marching on a treadmill. A group of eleven ethnicity- and age-matched civilians (age = 21.6 ± 0.7 years; height = 176.8 ± 4.3 cm; mass = 74.6 ± 5.6 kg) was also profiled and tested. Cadets and civilians exhibited similar morphology (muscle and tendon thickness and cross-sectional area, pennation angle, fascicle length) in 26 out of 29 sites including the Achilles tendon. However, patellar tendon thickness along the entire tendon was greater (P < .05) by a mean of 16% for the senior cadets compared with civilians. Dynamically, cadets showed significantly smaller ranges of fascicle length change and lower shortening velocity in medial gastrocnemius during walking (44.0% and 47.6%, P < .05-.01) and marching (27.5% and 34.3%, P < .05-.01) than civilians. Furthermore, cadets showed lower normalized soleus electrical activity during walking (22.7%, P < .05) and marching (27.0%, P < .05). Therefore, 24-36 months of continuous overloading, primarily occurring under aerobic conditions, leads to more efficient neural and mechanical behavior in the triceps surae complex, without any major macroscopic alterations in key anatomical structures.
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Affiliation(s)
| | | | - Josh Walker
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - Brian Hanley
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | | | - Thomas Metaxas
- Laboratory of Evaluation of Human Biological Performance, Department of Physical Education and Sport Science, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Kosmas Christoulas
- Laboratory of Evaluation of Human Biological Performance, Department of Physical Education and Sport Science, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Neil J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.,Department for Health, University of Bath, Bath, UK
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18
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Mesquita RNO, Cronin NJ, Kyröläinen H, Hintikka J, Avela J. Effects of caffeine on neuromuscular function in a non-fatigued state and during fatiguing exercise. Exp Physiol 2020; 105:690-706. [PMID: 32092208 DOI: 10.1113/ep088265] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 01/27/2020] [Indexed: 12/22/2022]
Abstract
NEW FINDINGS What is the central question of the study? What are the effects of caffeine on neuromuscular function in a non-fatigued state and during fatiguing exercise? What is the main finding and its importance? In a non-fatigued state, caffeine decreased the duration of the silent period evoked by transcranial magnetic stimulation. Caffeine-induced reduction of inhibitory mechanisms in the central nervous system before exercise was associated with an increased performance. Individuals who benefit from caffeine ingestion may experience lower perception of effort during exercise and an accelerated recovery of M-wave amplitude postfatigue. This study elucidates the mechanisms of action of caffeine and demonstrates that inter-individual variability of its effects on neuromuscular function is a fruitful area for further work. ABSTRACT Caffeine enhances exercise performance, but its mechanisms of action remain unclear. In this study, we investigated its effects on neuromuscular function in a non-fatigued state and during fatiguing exercise. Eighteen men participated in this randomized, double-blind, placebo-controlled crossover trial. Baseline measures included plantarflexion force, drop jump, squat jump, voluntary activation of triceps surae muscle, soleus muscle contractile properties, M-wave, α-motoneuron excitability (H-reflex), corticospinal excitability, short-interval intracortical inhibition, intracortical facilitation, silent period evoked by transcranial magnetic stimulation (SP) and plasma potassium and caffeine concentrations. Immediately after baseline testing, participants ingested caffeine (6 mg·kg-1 ) or placebo. After a 1-h rest, baseline measures were repeated, followed by a fatiguing stretch-shortening cycle exercise (sets of 40 bilateral rebound jumps on a sledge apparatus) until task failure. Neuromuscular testing was carried out throughout the fatigue protocol and afterwards. Caffeine enhanced drop jump height (by 4.2%) and decreased the SP (by 12.6%) in a non-fatigued state. A caffeine-related decrease in SP and short-interval intracortical inhibition before the fatiguing activity was associated with an increased time to task failure. The participants who benefitted from an improved performance on the caffeine day reported a significantly lower sense of effort during exercise and had an accelerated postexercise recovery of M-wave amplitude. Caffeine modulates inhibitory mechanisms of the CNS, recovery of M-wave amplitude and perception of effort. This study lays the groundwork for future examinations of differences in caffeine-induced neuromuscular changes between those who are deemed to benefit from caffeine ingestion and those who are not.
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Affiliation(s)
- Ricardo N O Mesquita
- School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia.,Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Neil J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.,Department for Health, Bath University, Bath, UK
| | - Heikki Kyröläinen
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Jukka Hintikka
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Janne Avela
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
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Seynnes OR, Cronin NJ. Simple Muscle Architecture Analysis (SMA): An ImageJ macro tool to automate measurements in B-mode ultrasound scans. PLoS One 2020; 15:e0229034. [PMID: 32049973 PMCID: PMC7015391 DOI: 10.1371/journal.pone.0229034] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 01/28/2020] [Indexed: 12/23/2022] Open
Abstract
In vivo measurements of muscle architecture (i.e. the spatial arrangement of muscle fascicles) are routinely included in research and clinical settings to monitor muscle structure, function and plasticity. However, in most cases such measurements are performed manually, and more reliable and time-efficient automated methods are either lacking completely, or are inaccessible to those without expertise in image analysis. In this work, we propose an ImageJ script to automate the entire analysis process of muscle architecture in ultrasound images: Simple Muscle Architecture Analysis (SMA). Images are filtered in the spatial and frequency domains with built-in commands and external plugins to highlight aponeuroses and fascicles. Fascicle dominant orientation is then computed in regions of interest using the OrientationJ plugin. Bland-Altman plots of analyses performed manually or with SMA indicate that the automated analysis does not induce any systematic bias and that both methods agree equally through the range of measurements. Our test results illustrate the suitability of SMA to analyse images from superficial muscles acquired with a broad range of ultrasound settings.
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Affiliation(s)
- Olivier R. Seynnes
- Department for Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
- * E-mail:
| | - Neil J. Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
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20
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Cronin NJ. Let the machine do the work: learning to reduce the energetic cost of walking on a split-belt treadmill. J Physiol 2019; 597:3791-3792. [PMID: 31264227 DOI: 10.1113/jp278459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
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21
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Werkhausen A, Cronin NJ, Albracht K, Bojsen-Møller J, Seynnes OR. Distinct muscle-tendon interaction during running at different speeds and in different loading conditions. J Appl Physiol (1985) 2019; 127:246-253. [PMID: 31070955 DOI: 10.1152/japplphysiol.00710.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The interaction between the Achilles tendon and the triceps surae muscles seems to be modulated differently with various task configurations. Here we tested the hypothesis that the increased forces and ankle joint work during running under contrasting conditions (altered speed or load) would be met by different, time-dependent adjustments at the muscle-tendon level. Ultrasonography, electromyography, kinematics, and ground reaction force measurements were used to examine Achilles tendon, gastrocnemius, and soleus muscle mechanics in 16 runners in four different running conditions, consisting of a combination of two different speeds (preferred and +20% of preferred speed) and two loading conditions (unloaded and +20% of body mass). Positive ankle joint work increased similarly (+13%) with speed and load. Gastrocnemius and soleus muscle fascicle length and peak velocity were not altered by either condition, suggesting that contractile conditions are mostly preserved despite the constraints imposed in this experimental design. However, at higher running speed, tendon length changes were unaltered but mean muscle electromyographic activity increased in gastrocnemius (+10%, P < 0.01) and soleus (+14%, P < 0.01). Conversely, when loading was increased, mean muscle activity remained similar to unloaded conditions but the mean velocity of gastrocnemius fascicles was reduced and tendon recoil increased (+29%, P < 0.01). Collectively, these results suggest that the neuromuscular system meets increased mechanical demands by favoring economical force production when enough time is available. NEW & NOTEWORTHY We demonstrate that muscle-tendon mechanics are adjusted differently when running under constraints imposed by speed or load, despite comparable increases in work. The neuromuscular system likely modulates the way force is produced as a function of availability of time and potential energy.
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Affiliation(s)
- Amelie Werkhausen
- Department of Physical Performance, Norwegian School of Sport Sciences , Oslo , Norway
| | - Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä , Jyväskylä , Finland
| | - Kirsten Albracht
- Institute of Biomechanics and Orthopedics, German Sport University Cologne , Cologne , Germany.,Department of Medical Engineering and Technomathematics, Aachen University of Applied Sciences , Aachen , Germany
| | - Jens Bojsen-Møller
- Department of Physical Performance, Norwegian School of Sport Sciences , Oslo , Norway
| | - Olivier R Seynnes
- Department of Physical Performance, Norwegian School of Sport Sciences , Oslo , Norway
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22
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Werkhausen A, Cronin NJ, Albracht K, Paulsen G, Larsen AV, Bojsen-Møller J, Seynnes OR. Training-induced increase in Achilles tendon stiffness affects tendon strain pattern during running. PeerJ 2019; 7:e6764. [PMID: 31086731 PMCID: PMC6486809 DOI: 10.7717/peerj.6764] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 03/06/2019] [Indexed: 12/14/2022] Open
Abstract
Background During the stance phase of running, the elasticity of the Achilles tendon enables the utilisation of elastic energy and allows beneficial contractile conditions for the triceps surae muscles. However, the effect of changes in tendon mechanical properties induced by chronic loading is still poorly understood. We tested the hypothesis that a training-induced increase in Achilles tendon stiffness would result in reduced tendon strain during the stance phase of running, which would reduce fascicle strains in the triceps surae muscles, particularly in the mono-articular soleus. Methods Eleven subjects were assigned to a training group performing isometric single-leg plantarflexion contractions three times per week for ten weeks, and another ten subjects formed a control group. Before and after the training period, Achilles tendon stiffness was estimated, and muscle-tendon mechanics were assessed during running at preferred speed using ultrasonography, kinematics and kinetics. Results Achilles tendon stiffness increased by 18% (P < 0.01) in the training group, but the associated reduction in strain seen during isometric contractions was not statistically significant. Tendon elongation during the stance phase of running was similar after training, but tendon recoil was reduced by 30% (P < 0.01), while estimated tendon force remained unchanged. Neither gastrocnemius medialis nor soleus fascicle shortening during stance was affected by training. Discussion These results show that a training-induced increase in Achilles tendon stiffness altered tendon behaviour during running. Despite training-induced changes in tendon mechanical properties and recoil behaviour, the data suggest that fascicle shortening patterns were preserved for the running speed that we examined. The asymmetrical changes in tendon strain patterns supports the notion that simple in-series models do not fully explain the mechanical output of the muscle-tendon unit during a complex task like running.
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Affiliation(s)
- Amelie Werkhausen
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Kirsten Albracht
- Institute of Biomechanics and Orthopedics, German Sport University Cologne, Cologne, Germany.,Department of Medical Engineering and Technomathematics, Aachen University of Applied Sciences, Aachen, Germany
| | - Gøran Paulsen
- The Norwegian Olympic and Paralympic Committee and Confederation of Sports, Oslo, Norway
| | - Askild V Larsen
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Jens Bojsen-Møller
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Olivier R Seynnes
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
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23
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Hegyi A, Csala D, Péter A, Finni T, Cronin NJ. High‐density electromyography activity in various hamstring exercises. Scand J Med Sci Sports 2018; 29:34-43. [DOI: 10.1111/sms.13303] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 09/07/2018] [Accepted: 09/12/2018] [Indexed: 11/28/2022]
Affiliation(s)
- András Hegyi
- Neuromuscular Research Center, Faculty of Sport and Health Sciences University of Jyvaskyla Finland
| | - Dániel Csala
- Department of Biomechanics University of Physical Education Budapest Hungary
| | - Annamária Péter
- Neuromuscular Research Center, Faculty of Sport and Health Sciences University of Jyvaskyla Finland
| | - Taija Finni
- Neuromuscular Research Center, Faculty of Sport and Health Sciences University of Jyvaskyla Finland
| | - Neil J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences University of Jyvaskyla Finland
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24
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Werkhausen A, Albracht K, Cronin NJ, Paulsen G, Bojsen-Møller J, Seynnes OR. Effect of Training-Induced Changes in Achilles Tendon Stiffness on Muscle-Tendon Behavior During Landing. Front Physiol 2018; 9:794. [PMID: 29997526 PMCID: PMC6028711 DOI: 10.3389/fphys.2018.00794] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/06/2018] [Indexed: 01/21/2023] Open
Abstract
During rapid deceleration of the body, tendons buffer part of the elongation of the muscle–tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of training-induced stiffening of the Achilles tendon on triceps surae muscle–tendon behavior during a landing task. Twenty-one male subjects were assigned to either a 10-week resistance-training program consisting of single-leg isometric plantarflexion (n = 11) or to a non-training control group (n = 10). Before and after the training period, plantarflexion force, peak Achilles tendon strain and stiffness were measured during isometric contractions, using a combination of dynamometry, ultrasound and kinematics data. Additionally, testing included a step-landing task, during which joint mechanics and lengths of gastrocnemius and soleus fascicles, Achilles tendon, and MTU were determined using synchronized ultrasound, kinematics and kinetics data collection. After training, plantarflexion strength and Achilles tendon stiffness increased (15 and 18%, respectively), and tendon strain during landing remained similar. Likewise, lengthening and negative work produced by the gastrocnemius MTU did not change detectably. However, in the training group, gastrocnemius fascicle length was offset (8%) to a longer length at touch down and, surprisingly, fascicle lengthening and velocity were reduced by 27 and 21%, respectively. These changes were not observed for soleus fascicles when accounting for variation in task execution between tests. These results indicate that a training-induced increase in tendon stiffness does not noticeably affect the buffering action of the tendon when the MTU is rapidly stretched. Reductions in gastrocnemius fascicle lengthening and lengthening velocity during landing occurred independently from tendon strain. Future studies are required to provide insight into the mechanisms underpinning these observations and their influence on energy dissipation.
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Affiliation(s)
- Amelie Werkhausen
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Kirsten Albracht
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Cologne, Germany.,Department of Medical Engineering and Technomathematics, Aachen University of Applied Sciences, Aachen, Germany
| | - Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Gøran Paulsen
- The Norwegian Olympic and Paralympic Committee and Confederation of Sports, Oslo, Norway
| | - Jens Bojsen-Møller
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Olivier R Seynnes
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
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25
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Hegyi A, Péter A, Finni T, Cronin NJ. Region-dependent hamstrings activity in Nordic hamstring exercise and stiff-leg deadlift defined with high-density electromyography. Scand J Med Sci Sports 2017; 28:992-1000. [PMID: 29143379 DOI: 10.1111/sms.13016] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2017] [Indexed: 01/03/2023]
Abstract
Recent studies suggest region-specific metabolic activity in hamstring muscles during injury prevention exercises, but the neural representation of this phenomenon is unknown. The aim of this study was to examine whether regional differences are evident in the activity of biceps femoris long head (BFlh) and semitendinosus (ST) muscles during two common injury prevention exercises. Twelve male participants without a history of hamstring injury performed the Nordic hamstring exercise (NHE) and stiff-leg deadlift (SDL) while BFlh and ST activities were recorded with high-density electromyography (HD-EMG). Normalized activity was calculated from the distal, middle, and proximal regions in the eccentric phase of each exercise. In NHE, ST overall activity was substantially higher than in BFlh (d = 1.06 ± 0.45), compared to trivial differences between muscles in SDL (d = 0.19 ± 0.34). Regional differences were found in NHE for both muscles, with different proximal-distal patterns: The distal region showed the lowest activity level in ST (regional differences, d range = 0.55-1.41) but the highest activity level in BFlh (regional differences, d range = 0.38-1.25). In SDL, regional differences were smaller in both muscles (d range = 0.29-0.67 and 0.16-0.63 in ST and BFlh, respectively) than in NHE. The use of HD-EMG in hamstrings revealed heterogeneous hamstrings activity during typical injury prevention exercises. High-density EMG might be useful in future studies to provide a comprehensive overview of hamstring muscle activity in other exercises and high-injury risk tasks.
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Affiliation(s)
- A Hegyi
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
| | - A Péter
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
| | - T Finni
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
| | - N J Cronin
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
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26
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Abstract
PURPOSE Older adults walk slower than young adults, but it is not known why. Previous research suggests that ankle plantarflexors may have a crucial role in the reduction of walking speed. The purpose of this study was to investigate age-related differences in triceps surae muscle-tendon function during walking to further investigate the role of plantarflexors in the age-related reduction of walking speed. METHODS Medial gastrocnemius and soleus muscle fascicle lengths were measured using ultrasound imaging during walking from 13 young (25 ± 4 yr) men at preferred walking speed and from 13 older (73 ± 5 yr) men at preferred speed and at the young men's preferred speed. Muscle-tendon unit lengths were calculated from joint kinematics, and tendinous tissue lengths were calculated by subtracting muscle lengths from muscle-tendon unit lengths. In addition, ground reaction forces and electromyographic activity of medial gastrocnemius and soleus were measured. RESULTS In both medial gastrocnemius and soleus, it was observed that at preferred walking speed, older men used a narrower muscle fascicle operating range and lower shortening velocity at the estimated time of triceps surae peak force generation compared with young men. Fascicles also accounted for a lower proportion of muscle-tendon unit length changes during the stance phase in older compared with young men. Significant differences in triceps surae muscle function were not observed between age groups when compared at matched walking speed. CONCLUSIONS In older men, walking at preferred speed allows triceps surae muscles to generate force with more favorable shortening velocity and to enhance use of tendinous tissue elasticity compared with walking at young men's preferred speed. The results suggest that older men may prefer slower walking speeds to compensate for decreased plantarflexor strength.
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Affiliation(s)
- Lauri Stenroth
- 1Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyvaskyla, Jyvaskyla, FINLAND; 2Department of Health Sciences, Gerontology Research Center, University of Jyvaskyla, Jyvaskyla, FINLAND
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27
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Werkhausen A, Albracht K, Cronin NJ, Meier R, Bojsen-Møller J, Seynnes OR. Modulation of muscle-tendon interaction in the human triceps surae during an energy dissipation task. ACTA ACUST UNITED AC 2017; 220:4141-4149. [PMID: 28883087 DOI: 10.1242/jeb.164111] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 09/06/2017] [Indexed: 11/20/2022]
Abstract
The compliance of elastic elements allows muscles to dissipate energy safely during eccentric contractions. This buffering function is well documented in animal models but our understanding of its mechanism in humans is confined to non-specific tasks, requiring a subsequent acceleration of the body. The present study aimed to examine the behaviour of the human triceps surae muscle-tendon unit (MTU) during a pure energy dissipation task, under two loading conditions. Thirty-nine subjects performed a single-leg landing task, with and without added mass. Ultrasound measurements were combined with three-dimensional kinematics and kinetics to determine instantaneous length changes of MTUs, muscle fascicles, Achilles tendon and combined elastic elements. Gastrocnemius and soleus MTUs lengthened during landing. After a small concentric action, fascicles contracted eccentrically during most of the task, whereas plantar flexor muscles were activated. Combined elastic elements lengthened until peak ankle moment and recoiled thereafter, whereas no recoil was observed for the Achilles tendon. Adding mass resulted in greater negative work and MTU lengthening, which were accompanied by a greater stretch of tendon and elastic elements and a greater recruitment of the soleus muscle, without any further fascicle strain. Hence, the buffering action of elastic elements delimits the maximal strain and lengthening velocity of active muscle fascicles and is commensurate with loading constraints. In the present task, energy dissipation was modulated via greater MTU excursion and more forceful eccentric contractions. The distinct strain pattern of the Achilles tendon supports the notion that different elastic elements may not systematically fulfil the same function.
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Affiliation(s)
- Amelie Werkhausen
- Department of Physical Performance, Norwegian School of Sport Sciences, Sognsveien 220, 0863 Oslo, Norway
| | - Kirsten Albracht
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933 Köln, Germany.,Medical Engineering and Technomathematics, University of Applied Sciences Aachen, Bayernallee 11, 52066 Aachen, Germany
| | - Neil J Cronin
- Department of Biology and Physical Activity, University of Jyväskylä, Seminaarinkatu 15, 40014 Jyväskylän yliopisto, Finland
| | - Rahel Meier
- Institute for Biomechanics, ETH Zurich, Rämistrasse 101, 8092 Zurich, Switzerland
| | - Jens Bojsen-Møller
- Department of Physical Performance, Norwegian School of Sport Sciences, Sognsveien 220, 0863 Oslo, Norway
| | - Olivier R Seynnes
- Department of Physical Performance, Norwegian School of Sport Sciences, Sognsveien 220, 0863 Oslo, Norway
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28
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Kümmel J, Cronin NJ, Kramer A, Avela J, Gruber M. Conditioning hops increase triceps surae muscle force and Achilles tendon strain energy in the stretch-shortening cycle. Scand J Med Sci Sports 2017; 28:126-137. [PMID: 28263394 DOI: 10.1111/sms.12870] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2017] [Indexed: 11/29/2022]
Abstract
Postactivation potentiation can improve athletic performance, but the underlying mechanisms are poorly understood. This study investigated the effect of conditioning hops on triceps surae muscle force and tendon strain and its contribution to potentiated stretch-shortening cycle (SSC) performance. Thirty-two subjects participated in two experiments. In both experiments, subjects performed three drop jumps (DJs) after prior conditioning with 10 maximal hops, three unconditioned DJs served as control. Ground reaction forces, kinematics, and triceps surae electromyographic activity were recorded. Ultrasound imaging was used to determine fascicle lengths (FASC) of the gastrocnemius (GM) and soleus muscles (experiment 1) and the length of the Achilles tendon (experiment 2) during the DJs. DJ height after the conditioning hops was significantly higher compared to control DJs (experiment 1: +12% and experiment 2: +19%). A significantly shorter GM FASC during the DJs performed after the conditioning hops coincided with an increased force acting on the triceps surae muscle. Moreover, the triceps surae muscle-tendon unit (MTU) showed increased energy absorption during the eccentric phase of the DJs and increased energy release during the concentric phase. The second experiment revealed a higher Achilles tendon strain in DJs performed after the conditioning hops compared to control DJs. No significant differences in muscle activities were observed. The shorter FASC in GM and the larger Achilles tendon strain facilitated MTU energy transfer from the eccentric to the concentric phase during the DJ. Thereby, conditioning hops improved SSC efficacy and DJ performance.
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Affiliation(s)
- J Kümmel
- Sensorimotor Performance Lab, Department of Sport Science, University of Konstanz, Konstanz, Germany
| | - N J Cronin
- Faculty of Sport and Health Sciences, NeuroMuscular Research Center, Unit of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - A Kramer
- Sensorimotor Performance Lab, Department of Sport Science, University of Konstanz, Konstanz, Germany
| | - J Avela
- Faculty of Sport and Health Sciences, NeuroMuscular Research Center, Unit of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - M Gruber
- Sensorimotor Performance Lab, Department of Sport Science, University of Konstanz, Konstanz, Germany
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29
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Péter A, Hegyi A, Finni T, Cronin NJ. In vivo fascicle behavior of the flexor hallucis longus muscle at different walking speeds. Scand J Med Sci Sports 2017; 27:1716-1723. [PMID: 28156022 DOI: 10.1111/sms.12810] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/31/2016] [Indexed: 12/27/2022]
Abstract
Ankle plantar flexor muscles support and propel the body in the stance phase of locomotion. Besides the triceps surae, flexor hallucis longus muscle (FHL) may also contribute to this role, but very few in vivo studies have examined FHL function during walking. Here, we investigated FHL fascicle behavior at different walking speeds. Ten healthy males walked overground at three different speeds while FHL fascicle length changes were recorded with ultrasound and muscle activity was recorded with surface electromyography (EMG). Fascicle length at heel strike at toe off and at peak EMG activity did not change with speed. Range of FHL fascicle length change (3.5-4.5 and 1.9-2.9 mm on average in stance and push-off phase, respectively), as well as minimum (53.5-54.9 and 53.8-55.7 mm) and maximum (58-58.4 and 56.8-57.7 mm) fascicle length did not change with speed in the stance or push-off phase. Mean fascicle velocity did not change in the stance phase, but increased significantly in the push-off phase between slow and fast walking speeds (P=.021). EMG activity increased significantly in both phases from slow to preferred and preferred to fast speed (P<.02 in all cases). FHL muscle fascicles worked near-isometrically during the whole stance phase (at least during slow walking) and operated at approximately the same length at different walking speeds. FHL and medial gastrocnemius (MG) have similar fiber length to muscle belly length ratios and, according to our results, also exhibit similar fascicle behavior at different walking speeds.
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Affiliation(s)
- A Péter
- Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyvaskyla, Jyvaskyla, Finland
| | - A Hegyi
- Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyvaskyla, Jyvaskyla, Finland
| | - T Finni
- Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyvaskyla, Jyvaskyla, Finland
| | - N J Cronin
- Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyvaskyla, Jyvaskyla, Finland
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30
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Kümmel J, Kramer A, Cronin NJ, Gruber M. Postactivation potentiation can counteract declines in force and power that occur after stretching. Scand J Med Sci Sports 2016; 27:1750-1760. [PMID: 27935646 DOI: 10.1111/sms.12817] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2016] [Indexed: 11/30/2022]
Abstract
Stretching can decrease a muscle's maximal force, whereas short but intense muscle contractions can increase it. We hypothesized that when combined, postactivation potentiation induced by reactive jumps would counteract stretch-induced decrements in drop jump (DJ) performance. Moreover, we measured changes in muscle twitch forces and ankle joint stiffness (KAnkle ) to examine underlying mechanisms. Twenty subjects completed three DJs and 10 electrically evoked muscle twitches of the triceps surae subsequent to four different conditioning activities and control. The conditioning activities were 10 hops, 20s of static stretching of the triceps surae muscle, 20s of stretching followed by 10 hops, and vice versa. After 10 hops, twitch peak torque (TPT) was 20% and jump height 5% higher compared with control with no differences in KAnkle . After stretching, TPT and jump height were both 9% and KAnkle 6% lower. When hops and stretching were combined as conditioning activities, jump height was not different compared with control but significantly higher (11% and 8%) compared with stretching. TPTs were 16% higher compared with control when the hops were performed after stretching and 9% higher compared with the reverse order. KAnkle was significantly lower when stretching was performed after the hops (6%) compared with control, but no significant difference was observed when hops were performed after stretching. These results demonstrate that conditioning hops can counteract stretch-related declines in DJ performance. Furthermore, the differences in TPTs and KAnkle between combined conditioning protocols indicate that the order of conditioning tasks might play an important role at the muscle-tendon level.
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Affiliation(s)
- J Kümmel
- Sensorimotor Performance Lab, Department of Sport Science, University of Konstanz, Konstanz, Germany
| | - A Kramer
- Sensorimotor Performance Lab, Department of Sport Science, University of Konstanz, Konstanz, Germany
| | - N J Cronin
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - M Gruber
- Sensorimotor Performance Lab, Department of Sport Science, University of Konstanz, Konstanz, Germany
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31
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Gao Y, Cronin NJ, Pesola AJ, Finni T. Muscle activity patterns and spinal shrinkage in office workers using a sit-stand workstation versus a sit workstation. Ergonomics 2016; 59:1267-1274. [PMID: 26853458 DOI: 10.1080/00140139.2016.1139750] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 12/23/2015] [Indexed: 06/05/2023]
Abstract
Reducing sitting time by means of sit-stand workstations is an emerging trend, but further evidence is needed regarding their health benefits. This cross-sectional study compared work time muscle activity patterns and spinal shrinkage between office workers (aged 24-62, 58.3% female) who used either a sit-stand workstation (Sit-Stand group, n = 10) or a traditional sit workstation (Sit group, n = 14) for at least the past three months. During one typical workday, muscle inactivity and activity from quadriceps and hamstrings were monitored using electromyography shorts, and spinal shrinkage was measured using stadiometry before and after the workday. Compared with the Sit group, the Sit-Stand group had less muscle inactivity time (66.2 ± 17.1% vs. 80.9 ± 6.4%, p = 0.014) and more light muscle activity time (26.1 ± 12.3% vs. 14.9 ± 6.3%, p = 0.019) with no significant difference in spinal shrinkage (5.62 ± 2.75 mm vs. 6.11 ± 2.44 mm). This study provides evidence that working with sit-stand workstations can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage. Practitioner Summary: This cross-sectional study compared the effects of using a sit-stand workstation to a sit workstation on muscle activity patterns and spinal shrinkage in office workers. It provides evidence that working with a sit-stand workstation can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage.
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Affiliation(s)
- Ying Gao
- a Department of Biology of Physical Activity, Neuromuscular Research Center , University of Jyväskylä , Jyväskylä , Finland
| | - Neil J Cronin
- a Department of Biology of Physical Activity, Neuromuscular Research Center , University of Jyväskylä , Jyväskylä , Finland
| | - Arto J Pesola
- a Department of Biology of Physical Activity, Neuromuscular Research Center , University of Jyväskylä , Jyväskylä , Finland
| | - Taija Finni
- a Department of Biology of Physical Activity, Neuromuscular Research Center , University of Jyväskylä , Jyväskylä , Finland
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32
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Cronin NJ, Hanley B, Bissas A. Mechanical and neural function of triceps surae in elite racewalking. J Appl Physiol (1985) 2016; 121:101-5. [PMID: 27255524 DOI: 10.1152/japplphysiol.00310.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 05/23/2016] [Indexed: 11/22/2022] Open
Abstract
Racewalking is a unique event combining mechanical elements of walking with speeds associated with running. It is currently unclear how racewalking technique impacts lower limb muscle-tendon function despite the relevance of this to muscle economy and overall performance. The present study examined triceps surae neuromechanics in 11 internationally competitive racewalkers (age 25 ± 11 yr) walking and running on a treadmill at speeds between 4.5 and 13.8 km/h while triceps surae fascicle lengths, electromyography, and kinematic data were recorded. Cumulative muscle activity required to traverse a unit distance (CMAPD) was calculated for each muscle. Medial gastrocnemius (MG) and soleus fascicle lengths/velocities were determined using an automated tracking algorithm, and muscle-tendon unit lengths were determined. Running was associated with net shortening of muscle fascicles during stance, combined with substantial lengthening of the muscle-tendon unit, implying energy storage in the Achilles tendon. When the same participants racewalked at the same speed, the fascicles shortened (soleus) or lengthened (MG), coinciding with rapid shortening followed by a relatively small increase in muscle-tendon length during stance. Consequently, compared with running at the same speed, racewalking decreased the energy-saving role of the Achilles tendon. Moreover, CMAPD was generally highest in racewalking, implying that in individual muscles, the energy cost of racewalking was higher than running. Together these results suggest that racewalking is neurally and mechanically costly relative to running at a given speed. As racewalking events are typically between 10 and 50 km, neuromechanical inefficiencies that occur with each stride likely result in substantial energetic penalties.
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Affiliation(s)
- Neil J Cronin
- University of Jyvaskyla, Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyvaskyla, Finland; and
| | - Brian Hanley
- School of Sport, Carnegie Faculty, Leeds Beckett University, United Kingdom
| | - Athanassios Bissas
- School of Sport, Carnegie Faculty, Leeds Beckett University, United Kingdom
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33
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Stenroth L, Cronin NJ, Peltonen J, Korhonen MT, Sipilä S, Finni T. Triceps surae muscle-tendon properties in older endurance- and sprint-trained athletes. J Appl Physiol (1985) 2016; 120:63-9. [DOI: 10.1152/japplphysiol.00511.2015] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 10/19/2015] [Indexed: 12/21/2022] Open
Abstract
Previous studies have shown that aging is associated with alterations in muscle architecture and tendon properties (Morse CI, Thom JM, Birch KM, Narici MV. Acta Physiol Scand 183: 291–298, 2005; Narici MV, Maganaris CN, Reeves ND, Capodaglio P. J Appl Physiol 95: 2229–2234, 2003; Stenroth L, Peltonen J, Cronin NJ, Sipila S, Finni T. J Appl Physiol 113: 1537–1544, 2012). However, the possible influence of different types of regular exercise loading on muscle architecture and tendon properties in older adults is poorly understood. To address this, triceps surae muscle-tendon properties were examined in older male endurance (OE, n = 10, age = 74.0 ± 2.8 yr) and sprint runners (OS, n = 10, age = 74.4 ± 2.8 yr), with an average of 42 yr of regular training experience, and compared with age-matched [older control (OC), n = 33, age = 74.8 ± 3.6 yr] and young untrained controls (YC, n = 18, age = 23.7 ± 2.0 yr). Compared with YC, Achilles tendon cross-sectional area (CSA) was 22% ( P = 0.022), 45% ( P = 0.001), and 71% ( P < 0.001) larger in OC, OE, and OS, respectively. Among older groups, OS had significantly larger tendon CSA compared with OC ( P = 0.033). No significant between-group differences were observed in Achilles tendon stiffness. In older groups, Young's modulus was 31-44%, and maximal tendon stress 44–55% lower, than in YC ( P ≤ 0.001). OE showed shorter soleus fascicle length than both OC ( P < 0.05) and YC ( P < 0.05). These data suggest that long-term running does not counteract the previously reported age-related increase in tendon CSA, but, instead, may have an additive effect. The greatest Achilles tendon CSA was observed in OS followed by OE and OC, suggesting that adaptation to running exercise is loading intensity dependent. Achilles tendon stiffness was maintained in older groups, even though all older groups displayed larger tendon CSA and lower tendon Young's modulus. Shorter soleus muscle fascicles in OE runners may be an adaptation to life-long endurance running.
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Affiliation(s)
- Lauri Stenroth
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyvaskyla, Jyvaskyla, Finland; and
- Gerontology Research Center and Department of Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
| | - Neil J. Cronin
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyvaskyla, Jyvaskyla, Finland; and
| | - Jussi Peltonen
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyvaskyla, Jyvaskyla, Finland; and
| | - Marko T. Korhonen
- Gerontology Research Center and Department of Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
| | - Sarianna Sipilä
- Gerontology Research Center and Department of Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland
| | - Taija Finni
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyvaskyla, Jyvaskyla, Finland; and
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Finni T, Cronin NJ, Mayfield D, Lichtwark GA, Cresswell AG. Effects of muscle activation on shear between human soleus and gastrocnemius muscles. Scand J Med Sci Sports 2015; 27:26-34. [PMID: 26643762 DOI: 10.1111/sms.12615] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2015] [Indexed: 11/30/2022]
Abstract
Lateral connections between muscles provide pathways for myofascial force transmission. To elucidate whether these pathways have functional roles in vivo, we examined whether activation could alter the shear between the soleus (SOL) and lateral gastrocnemius (LG) muscles. We hypothesized that selective activation of LG would decrease the stretch-induced shear between LG and SOL. Eleven volunteers underwent a series of knee joint manipulations where plantar flexion force, LG, and SOL muscle fascicle lengths and relative displacement of aponeuroses between the muscles were obtained. Data during a passive full range of motion were recorded, followed by 20° knee extension stretches in both passive conditions and with selective electrical stimulation of LG. During active stretch, plantar flexion force was 22% greater (P < 0.05) and relative displacement of aponeuroses was smaller than during passive stretch (P < 0.05). Soleus fascicle length changes did not differ between passive and active stretches but LG fascicles stretched less in the active than passive condition when the stretch began at angles of 70° and 90° of knee flexion (P < 0.05). The activity-induced decrease in the relative displacement of SOL and LG suggests stronger (stiffer) connectivity between the two muscles, at least at flexed knee joint angles, which may serve to facilitate myofascial force transmission.
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Affiliation(s)
- T Finni
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyvaskyla, Jyvaskyla, Finland
| | - N J Cronin
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyvaskyla, Jyvaskyla, Finland
| | - D Mayfield
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - G A Lichtwark
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - A G Cresswell
- Centre for Sensorimotor Performance, School of Human Movement and Nutrition Sciences, The University of Queensland, St Lucia, Queensland, Australia
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Gao Y, Nevala N, Cronin NJ, Finni T. Effects of environmental intervention on sedentary time, musculoskeletal comfort and work ability in office workers. Eur J Sport Sci 2015; 16:747-54. [DOI: 10.1080/17461391.2015.1106590] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Mayfield DL, Lichtwark GA, Cronin NJ, Avela J, Cresswell AG. Doublet potentiation in the triceps surae is limited by series compliance and dynamic fascicle behavior. J Appl Physiol (1985) 2015; 119:807-16. [DOI: 10.1152/japplphysiol.00403.2015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 08/03/2015] [Indexed: 11/22/2022] Open
Abstract
Activation of skeletal muscle twice in quick succession results in nonlinear force summation (i.e., doublet potentiation). The force contributed by a second activation is typically of augmented amplitude, longer in duration, and generated at a greater rate. The purpose of this study was to examine force summation in a muscle attached to a compliant tendon, where considerable internal shortening occurs during a fixed-end contraction. The triceps surae of 21 ( Experiment 1) and 9 ( Experiment 2) young adults were maximally activated with doublet stimulation of different interstimulus intervals (ISIs) (5-100 ms) at several muscle lengths. Ultrasound images acquired from lateral gastrocnemius and soleus muscles allowed quantification of dynamic fascicle behavior. Force summation was muscle length dependent. Force augmentation was limited to a short muscle length. Lateral gastrocnemius and soleus fascicles underwent large amounts of active shortening and achieved high velocities in response to doublet stimulation, dynamics unfavorable for force production. Summation amplitude and the sensitivity of summation to ISI were dramatically depressed in the triceps surae after comparison to muscles with less fixed-end compliance. We propose that the internal shortening permitted by high series compliance limited force augmentation by offsetting and/or interfering with activation and cross-bridge processes driving augmentation. High series compliance may also reduce the sensitivity of the summated response to ISI, an assertion supported by predictions from a Hill-type muscle model. These muscles may exhibit greater force augmentation during more accustomed stretch-shorten tasks (i.e., hopping), where the compliance of the Achilles tendon actually enables near-isometric fascicle behavior.
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Affiliation(s)
- Dean L. Mayfield
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia
| | - Glen A. Lichtwark
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia
| | - Neil J. Cronin
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Janne Avela
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Andrew G. Cresswell
- School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia
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Péter A, Hegyi A, Stenroth L, Finni T, Cronin NJ. EMG and force production of the flexor hallucis longus muscle in isometric plantarflexion and the push-off phase of walking. J Biomech 2015; 48:3413-9. [DOI: 10.1016/j.jbiomech.2015.05.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 03/23/2015] [Accepted: 05/30/2015] [Indexed: 10/23/2022]
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Cronin NJ, Kumpulainen S, Joutjärvi T, Finni T, Piitulainen H. Spatial variability of muscle activity during human walking: the effects of different EMG normalization approaches. Neuroscience 2015; 300:19-28. [PMID: 25967267 DOI: 10.1016/j.neuroscience.2015.05.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/30/2015] [Accepted: 05/01/2015] [Indexed: 11/16/2022]
Abstract
Human leg muscles are often activated inhomogeneously, e.g. in standing. This may also occur in complex tasks like walking. Thus, bipolar surface electromyography (sEMG) may not accurately represent whole muscle activity. This study used 64-electrode high-density sEMG (HD-sEMG) to examine spatial variability of lateral gastrocnemius (LG) muscle activity during the stance phase of walking, maximal voluntary contractions (MVCs) and maximal M-waves, and determined the effects of different normalization approaches on spatial and inter-participant variability. Plantar flexion MVC, maximal electrically elicited M-waves and walking at self-selected speed were recorded in eight healthy males aged 24-34. sEMG signals were assessed in four ways: unnormalized, and normalized to MVC, M-wave or peak sEMG during the stance phase of walking. During walking, LG activity varied spatially, and was largest in the distal and lateral regions. Spatial variability fluctuated throughout the stance phase. Normalizing walking EMG signals to the peak value during stance reduced spatial variability within LG on average by 70%, and inter-participant variability by 67%. Normalizing to MVC reduced spatial variability by 17% but increased inter-participant variability by 230%. Normalizing to M-wave produced the greatest spatial variability (45% greater than unnormalized EMG) and increased inter-participant variability by 70%. Unnormalized bipolar LG sEMG may provide misleading results about representative muscle activity in walking due to spatial variability. For the peak value and MVC approaches, different electrode locations likely have minor effects on normalized results, whereas electrode location should be carefully considered when normalizing walking sEMG data to maximal M-waves.
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Affiliation(s)
- N J Cronin
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.
| | - S Kumpulainen
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland
| | - T Joutjärvi
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland
| | - T Finni
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland
| | - H Piitulainen
- Brain Research Unit, O.V. Lounasmaa Laboratory, Aalto University School of Science, P.O. Box 15100, 00076 AALTO, Espoo, Finland
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Carty CP, Cronin NJ, Nicholson D, Lichtwark GA, Mills PM, Kerr G, Cresswell AG, Barrett RS. Reactive stepping behaviour in response to forward loss of balance predicts future falls in community-dwelling older adults. Age Ageing 2015; 44:109-15. [PMID: 24918170 DOI: 10.1093/ageing/afu054] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND a fall occurs when an individual experiences a loss of balance from which they are unable to recover. Assessment of balance recovery ability in older adults may therefore help to identify individuals at risk of falls. The purpose of this 12-month prospective study was to assess whether the ability to recover from a forward loss of balance with a single step across a range of lean magnitudes was predictive of falls. METHODS two hundred and one community-dwelling older adults, aged 65-90 years, underwent baseline testing of sensori-motor function and balance recovery ability followed by 12-month prospective falls evaluation. Balance recovery ability was defined by whether participants required either single or multiple steps to recover from forward loss of balance from three lean magnitudes, as well as the maximum lean magnitude participants could recover from with a single step. RESULTS forty-four (22%) participants experienced one or more falls during the follow-up period. Maximal recoverable lean magnitude and use of multiple steps to recover at the 15% body weight (BW) and 25%BW lean magnitudes significantly predicted a future fall (odds ratios 1.08-1.26). The Physiological Profile Assessment, an established tool that assesses variety of sensori-motor aspects of falls risk, was also predictive of falls (Odds ratios 1.22 and 1.27, respectively), whereas age, sex, postural sway and timed up and go were not predictive. CONCLUSION reactive stepping behaviour in response to forward loss of balance and physiological profile assessment are independent predictors of a future fall in community-dwelling older adults. Exercise interventions designed to improve reactive stepping behaviour may protect against future falls.
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Affiliation(s)
- Christopher P Carty
- Centre for Musculoskeletal Research, Griffith Health Institute and School of Allied Health Sciences, Griffith University, Gold Coast, Australia
| | - Neil J Cronin
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Deanne Nicholson
- Centre for Musculoskeletal Research, Griffith Health Institute and School of Allied Health Sciences, Griffith University, Gold Coast, Australia
| | - Glen A Lichtwark
- School of Human Movement Studies, The University of Queensland, Brisbane, Australia
| | - Peter M Mills
- Centre for Musculoskeletal Research, Griffith Health Institute and School of Allied Health Sciences, Griffith University, Gold Coast, Australia
| | - Graham Kerr
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia
| | - Andrew G Cresswell
- School of Human Movement Studies, The University of Queensland, Brisbane, Australia
| | - Rod S Barrett
- Centre for Musculoskeletal Research, Griffith Health Institute and School of Allied Health Sciences, Griffith University, Gold Coast, Australia
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Cronin NJ, Rantalainen T, Avela J. Triceps surae fascicle stretch is poorly correlated with short latency stretch reflex size. Muscle Nerve 2014; 52:245-51. [PMID: 25487638 DOI: 10.1002/mus.24538] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/02/2014] [Indexed: 11/06/2022]
Abstract
INTRODUCTION The short latency stretch reflex (SLR) is well described, but the stimulus that evokes the SLR remains elusive. One hypothesis states that reflex size is proportional to muscle fiber stretch, so in this study we examined the relationship between these 2 parameters in human triceps surae muscles. METHODS Achilles tendon taps and dorsiflexion stretches with different amplitudes and preactivation torques were applied to 6 participants while electromyography and muscle fascicle length changes were recorded in soleus and medial gastrocnemius (MG). RESULTS In response to tendon taps, neither fascicle length nor velocity changes were correlated with SLR size in either muscle, but accelerometer peaks were observed immediately after hammer-tendon contact. Similar results were obtained after dorsiflexion stretches. CONCLUSION Muscle fascicle stretch is poorly correlated with SLR size, regardless of perturbation parameters. We attribute the SLR trigger to the transmission of vibration through the lower limb, rather than muscle fiber stretch.
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Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Viveca, P.O. Box 35, Jyväskylä, 40014, Finland
| | - Timo Rantalainen
- Centre for Physical Activity and Nutrition Research, School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria, Australia
| | - Janne Avela
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Viveca, P.O. Box 35, Jyväskylä, 40014, Finland
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Piirainen JM, Cronin NJ, Avela J, Linnamo V. Effects of plyometric and pneumatic explosive strength training on neuromuscular function and dynamic balance control in 60–70year old males. J Electromyogr Kinesiol 2014; 24:246-52. [DOI: 10.1016/j.jelekin.2014.01.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Revised: 12/03/2013] [Accepted: 01/31/2014] [Indexed: 10/25/2022] Open
Affiliation(s)
- Jarmo M Piirainen
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland.
| | - Neil J Cronin
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland
| | - Janne Avela
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland
| | - Vesa Linnamo
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland
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Cronin NJ. The effects of high heeled shoes on female gait: a review. J Electromyogr Kinesiol 2014; 24:258-63. [PMID: 24508305 DOI: 10.1016/j.jelekin.2014.01.004] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 01/09/2014] [Accepted: 01/14/2014] [Indexed: 11/26/2022] Open
Abstract
Walking is the most common form of human locomotion. From a motor control perspective, human bipedalism makes the task of walking extremely complex. For parts of the step cycle, there is only one foot on the ground, so both balance and propulsion are required in order for the movement to proceed smoothly. One condition known to compound the difficulty of walking is the use of high heeled shoes, which alter the natural position of the foot-ankle complex, and thereby produce a chain reaction of (mostly negative) effects that travels up the lower limb at least as far as the spine. This review summarises recent studies that have examined acute and chronic effects of high heels on balance and locomotion in young, otherwise healthy women. Controversial issues, common study limitations and directions for future research are also addressed in detail.
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Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, Finland.
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Piirainen JM, Linnamo V, Cronin NJ, Avela J. Age-related neuromuscular function and dynamic balance control during slow and fast balance perturbations. J Neurophysiol 2013; 110:2557-62. [PMID: 24047908 DOI: 10.1152/jn.00476.2013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study investigated age-related differences in dynamic balance control and its connection to reflexes and explosive isometric plantar flexor torque in 19 males (9 Young aged 20–33 yr, 10 Elderly aged 61–72 yr). Dynamic balance was measured during Slow (15 cm/s) and Fast (25 cm/s) anterior and posterior perturbations. H/M-ratio was measured at 20% of maximal M-wave (H/M20%) 10, 30, and 90 ms after perturbations. Stretch reflexes were measured from tibialis anterior and soleus during anterior and posterior perturbations, respectively. In Slow, Elderly exhibited larger peak center-of-pressure (COP) displacement (15%; P < 0.05) during anterior perturbations. In Fast, Young showed a trend for faster recovery (37%; P = 0.086) after anterior perturbations. M-wave latency was similar between groups (6.2 ± 0.7 vs. 6.9 ± 1.2 ms), whereas Elderly showed a longer H-reflex latency (33.7 ± 2.3 vs. 36.4 ± 1.7 ms; P < 0.01). H/M20% was higher in Young 30 ms after Fast anterior (50%; P < 0.05) and posterior (51%; P < 0.05) perturbations. Plantar flexor rapid torque was also higher in Young (26%; P < 0.05). After combining both groups' data, H/M20% correlated negatively with Slow peak COP displacement ( r = −0.510, P < 0.05) and positively with Fast recovery time ( r = 0.580, P < 0.05) for anterior perturbations. Age-related differences in balance control seem to be more evident in anterior than posterior perturbations, and rapid sensory feedback is generally important for balance perturbation recovery.
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Affiliation(s)
- Jarmo M. Piirainen
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Vesa Linnamo
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Neil J. Cronin
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
| | - Janne Avela
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland
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Cronin NJ, Barrett RS, Lichtwark G, Mills PM, Carty CP. Decreased lower limb muscle recruitment contributes to the inability of older adults to recover with a single step following a forward loss of balance. J Electromyogr Kinesiol 2013; 23:1139-44. [DOI: 10.1016/j.jelekin.2013.05.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/20/2013] [Accepted: 05/20/2013] [Indexed: 11/30/2022] Open
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Cronin NJ, Finni T. Treadmill versus overground and barefoot versus shod comparisons of triceps surae fascicle behaviour in human walking and running. Gait Posture 2013; 38:528-33. [PMID: 23473808 DOI: 10.1016/j.gaitpost.2013.01.027] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 01/16/2013] [Accepted: 01/30/2013] [Indexed: 02/02/2023]
Abstract
Studies of human locomotion are commonly performed on a treadmill or overground, as well as with or without footwear. These testing modalities have been suggested to influence kinematics, kinetics and/or spatio-temporal variables differently. However, it is unclear whether they influence contractile behaviour at the level of the muscle fascicles. This has major relevance because results from studies performed with different combinations of the testing modalities are often compared. The present study used ultrasound to examine fascicle behaviour of the medial gastrocnemius (MG) and soleus muscles of ten young, healthy males during walking and running on a treadmill and overground, as well as barefoot and shod. Barefoot conditions resulted in modestly shorter step durations than corresponding shod conditions, whereas no consistent temporal differences were observed between overground and treadmill locomotion. For both comparisons, no differences were observed in soleus or MG fascicle behaviour between corresponding conditions in walking or running, although soleus consistently exhibited smaller, lower velocity length changes than MG. It is concluded that the examined testing modalities are equally valid for studying muscle fascicle behaviour during locomotion. This conclusion is supported by a comparison of our data to the results of 16 previous studies that used various combinations of testing modalities; muscle fascicle behaviour is qualitatively similar between studies for a given muscle and gait.
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Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, Finland.
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Peltonen J, Cronin NJ, Stenroth L, Finni T, Avela J. Viscoelastic properties of the Achilles tendon in vivo. Springerplus 2013; 2:212. [PMID: 23710431 PMCID: PMC3661039 DOI: 10.1186/2193-1801-2-212] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 04/25/2013] [Indexed: 11/10/2022]
Abstract
It has been postulated that human tendons are viscoelastic and their mechanical properties time-dependent. Although Achilles tendon (AT) mechanics are widely reported, there is no consensus about AT viscoelastic properties such as loading rate dependency or hysteresis, in vivo. AT force-elongation characteristics were determined from 14 subjects in an ankle dynamometer at different loading rates using motion capture assisted ultrasonography. AT stiffness and elongation were determined between 10 - 80% of maximum voluntary contraction (MVC) force at fast and slow loading rates. As subjects were unable to consistently match the target unloading rate in the slow condition, AT hysteresis was only calculated for the fast rate. There was a significant difference between the fast and the slow loading rates: 120 ± 6 vs. 21 ± 1% of MVC s(-1) (mean ± standard error), respectively. However, neither stiffness (193 ± 18 N mm(-1) vs. 207 ± 22 N mm(-1)) nor elongation at any force level (13.0 ± 1.2 mm vs. 14.3 ± 0.9 mm at 80% of MVC) were significantly different between the fast and slow loading rates. Tendon hysteresis at the fast rate was 5 ± 2%. As stiffness was not sensitive to loading rate and hysteresis was small, it was concluded that elastic properties prevail over viscous properties in the human AT. The current results support the idea that AT stiffness is independent of loading rate.
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Affiliation(s)
- Jussi Peltonen
- Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, Finland
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Cronin NJ, Prilutsky BI, Lichtwark GA, Maas H. Does ankle joint power reflect type of muscle action of soleus and gastrocnemius during walking in cats and humans? J Biomech 2013; 46:1383-6. [PMID: 23538001 DOI: 10.1016/j.jbiomech.2013.02.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 12/01/2022]
Abstract
The main objective of this paper is to highlight the difficulties of identifying shortening and lengthening contractions based on analysis of power produced by resultant joint moments. For that purpose, we present net ankle joint powers and muscle fascicle/muscle-tendon unit (MTU) velocities for medial gastrocnemius (MG) and soleus (SO) muscles during walking in species of different size (humans and cats). For the cat, patterns of ankle joint power and MTU velocity of MG and SO during stance were similar: negative power (ankle moment×angular velocity<0), indicating absorption of mechanical energy, was associated with MTU lengthening, and positive power (generation of mechanical energy) was found during MTU shortening. This was also found for the general fascicle velocity pattern in SO. In contrast, substantial differences between ankle joint power and fascicle velocity patterns were observed for MG muscle. In humans, like cats, the patterns of ankle joint power and MTU velocity of SO and MG were similar. Unlike the cat, there were substantial differences between patterns of fascicle velocity and ankle joint power during stance in both muscles. These results indicate that during walking, only a small fraction of mechanical work of the ankle moment is either generated or absorbed by the muscle fascicles, thus confirming the contribution of in-series elastic structures and/or energy transfer via two-joint muscles. We conclude that ankle joint negative power does not necessarily indicate eccentric action of muscle fibers and that positive power cannot be exclusively attributed to muscle concentric action, especially in humans.
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Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, Finland
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Cronin NJ, Lichtwark G. The use of ultrasound to study muscle-tendon function in human posture and locomotion. Gait Posture 2013; 37:305-12. [PMID: 22910172 DOI: 10.1016/j.gaitpost.2012.07.024] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 07/26/2012] [Accepted: 07/28/2012] [Indexed: 02/02/2023]
Abstract
Analysis of human movement has traditionally relied on measures such as kinematics, kinetics and electromyography. These measures provide valuable information about movement performance and make it possible to draw inferences about muscle and tendon function. Musculoskeletal models are also used frequently to examine the relationship between joint kinematics and muscle-tendon behaviour, and have provided important insights into both healthy and clinical gait. However, muscles interact with compliant tendons during movement, which complicates interpretation of muscle and tendon function based on external measures such as joint kinematics. Accordingly, methods have been developed that enable muscle and tendinous tissues to be imaged in real-time. Ultrasound is among the most popular methods used for this purpose, and has been applied extensively to the study of in vivo muscle and tendon function in a range of human populations and movement contexts. There is a growing body of literature that proposes different measures of muscle and/or tendon function, and these results need to be discussed in light of the technical differences between the measurement techniques. In this review we first outline the various uses of ultrasound to examine human muscle and tendon function, and then summarise ultrasound-based research specifically during locomotion and postural conditions. We then describe some of the many technical issues associated with this method. Methods of data analysis are introduced, including novel automated techniques that improve the efficiency of the analysis process. Finally, possible future directions in musculoskeletal ultrasound research are discussed.
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Affiliation(s)
- Neil J Cronin
- Neuromuscular Research Centre, Department of Biology of Physical Activity, University of Jyväskylä, Finland.
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Abstract
Overuse-induced injuries have been proposed as a predisposing factor for Achilles tendon (AT) ruptures. If tendons can be overloaded, their mechanical properties should change during exercise. Because there data are lacking on the effects of a single bout of long-lasting exercise on AT mechanical properties, the present study measured AT stiffness before and after a marathon. AT stiffness was determined as the slope of the force-elongation curve between 10 and 80% of maximum voluntary force. AT force-elongation characteristics were measured in an ankle dynamometer using simultaneous motion-capture-assisted ultrasonography. Oxygen consumption and ankle kinematics were also measured on a treadmill at the marathon pace. All measurements were performed before and after the marathon. AT stiffness did not change significantly from the pre-race value of 197±62 N mm(-1) (mean ± s.d.) to the post-race value of 206±59 N mm(-1) (N=12, P=0.312). Oxygen consumption increased after the race by 7±10% (P<0.05) and ankle kinematic data revealed that in nine out of 12 subjects, the marathon induced a change in their foot strike technique. The AT of the physically active individuals seems to be able to resist mechanical changes under physiological stress. We therefore suggest that natural loading, like in running, may not overstress the AT or predispose it to injury. In addition, decreased running economy, as well as altered foot strike technique, was probably attributable to muscle fatigue.
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Affiliation(s)
- Jussi Peltonen
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä 40014, Finland.
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Affiliation(s)
- Taija Finni
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland
| | - Jussi Peltonen
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland
| | - Lauri Stenroth
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland
| | - Neil J. Cronin
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Finland
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