1
|
Compton CT, Lockyer EJ, Benson RJ, Power KE. Interhemispheric inhibition is different during arm cycling than a position- and intensity-matched tonic contraction. Exp Brain Res 2022; 240:2425-2434. [DOI: 10.1007/s00221-022-06413-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 07/01/2022] [Indexed: 11/29/2022]
|
2
|
Sensory enhancement of warm-up amplifies subsequent grip strength and cycling performance. Eur J Appl Physiol 2022; 122:1695-1707. [PMID: 35471257 DOI: 10.1007/s00421-022-04952-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 04/08/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE In sport and exercise, warm-ups induce various physiological changes that facilitate subsequent performance. We have shown that delivering patterned stimulation to cutaneous afferents during sprint cycling mitigates fatigue-related decrements in performance, and that repeated sensory stimulation amplifies spinal reflex excitability. Therefore, the purpose of this study was to assess whether sensory enhancement of warm-up would affect subsequent high-intensity arm cycling performance. METHODS Participants completed three experimental sessions, in which they randomly performed either a control, stim, or sleeve warm-up condition prior to maximal duration arm cycling. During the control condition, warmup consisted of low-intensity arm cycling for 15 min. The stim condition was the same, except they received alternating pulses (400 ms, 50 Hz) of stimulation just above their perceptual threshold to the wrists during warm-up. The third condition required participants to wear custom fabricated compression sleeves around the elbow during warm-up. Grip strength and spinal reflex excitability were measured before and after each warm-up and fatigue protocol, which required participants to arm cycle at 85% of peak power output until they reached volitional fatigue. Peak power output was determined during an incremental test at minimum 72 h prior to the first session. RESULTS Both sensory enhanced warm-up conditions amplified subsequent high-intensity arm cycling performance by ~ 30%. Additionally, the stim and sleeve warm-up conditions yielded improvements in grip strength (increased by ~ 5%) immediately after the sensory enhanced warm-ups. Ergogenic benefits from the sensory enhanced warm-up conditions did not differ between one another. CONCLUSION These findings demonstrate that enhanced sensory input during warm-up can elicit improvements in both maximal and submaximal performance measures.
Collapse
|
3
|
Clos P, Mater A, Legrand H, Poirier G, Ballay Y, Martin A, Lepers R. Corticospinal Excitability Is Lower During Eccentric Than Concentric Cycling in Men. Front Physiol 2022; 13:854824. [PMID: 35370788 PMCID: PMC8966379 DOI: 10.3389/fphys.2022.854824] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/14/2022] [Indexed: 11/16/2022] Open
Abstract
How corticospinal excitability changes during eccentric locomotor exercise is unknown. In the present study, 13 volunteers performed 30-min strenuous concentric and eccentric cycling bouts at the same power output (60% concentric peak power output). Transcranial magnetic and electrical femoral nerve stimulations were applied at exercise onset (3rd min) and end (25th min). Motor-evoked potentials (MEPs) amplitude was measured for the rectus femoris (RF) and vastus lateralis (VL) muscles with surface electromyography (EMG) and expressed as a percentage of maximal M-wave amplitude (MMAX). EMG amplitude 100 ms prior to MEPs and the silent period duration were calculated. There was no change in any neural parameter during the exercises (all P > 0.24). VL and RF MMAX were unaffected by exercise modality (all P > 0.38). VL MEP amplitude was greater (26 ± 11.4 vs. 15.2 ± 7.7% MMAX; P = 0.008) during concentric than eccentric cycling whereas RF MEP amplitude was not different (24.4 ± 10.8 vs. 17.2 ± 9.8% MMAX; P = 0.051). While VL EMG was higher during concentric than eccentric cycling (P = 0.03), RF EMG showed no significant difference (P = 0.07). Similar silent period durations were found (RF: 120 ± 30 ms; VL: 114 ± 27 ms; all P > 0.61), but the silent period/MEP ratio was higher during eccentric than concentric cycling for both muscles (all P < 0.02). In conclusion, corticospinal excitability to the knee extensors is lower and relative silent period longer during eccentric than concentric cycling, yet both remained unaltered with time.
Collapse
|
4
|
Power KE, Lockyer EJ, Botter A, Vieira T, Button DC. Endurance-exercise training adaptations in spinal motoneurones: potential functional relevance to locomotor output and assessment in humans. Eur J Appl Physiol 2022; 122:1367-1381. [PMID: 35226169 DOI: 10.1007/s00421-022-04918-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 02/11/2022] [Indexed: 12/14/2022]
Abstract
It is clear from non-human animal work that spinal motoneurones undergo endurance training (chronic) and locomotor (acute) related changes in their electrical properties and thus their ability to fire action potentials in response to synaptic input. The functional implications of these changes, however, are speculative. In humans, data suggests that similar chronic and acute changes in motoneurone excitability may occur, though the work is limited due to technical constraints. To examine the potential influence of chronic changes in human motoneurone excitability on the acute changes that occur during locomotor output, we must develop more sophisticated recording techniques or adapt our current methods. In this review, we briefly discuss chronic and acute changes in motoneurone excitability arising from non-human and human work. We then discuss the potential interaction effects of chronic and acute changes in motoneurone excitability and the potential impact on locomotor output. Finally, we discuss the use of high-density surface electromyogram recordings to examine human motor unit firing patterns and thus, indirectly, motoneurone excitability. The assessment of single motor units from high-density recording is mainly limited to tonic motor outputs and minimally dynamic motor output such as postural sway. Adapting this technology for use during locomotor outputs would allow us to gain a better understanding of the potential functional implications of endurance training-induced changes in human motoneurone excitability on motor output.
Collapse
Affiliation(s)
- Kevin E Power
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada. .,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - Evan J Lockyer
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Alberto Botter
- Laboratory for Engineering of the Neuromuscular System (LISiN), Department of Electronics and Telecommunication, Politecnico di Torino, Turin, Italy.,PoliToBIOMed Lab, Politecnico di Torino, Turin, Italy
| | - Taian Vieira
- Laboratory for Engineering of the Neuromuscular System (LISiN), Department of Electronics and Telecommunication, Politecnico di Torino, Turin, Italy.,PoliToBIOMed Lab, Politecnico di Torino, Turin, Italy
| | - Duane C Button
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| |
Collapse
|
5
|
Lockyer EJ, Compton CT, Forman DA, Pearcey GE, Button DC, Power KE. Moving forward: methodological considerations for assessing corticospinal excitability during rhythmic motor output in humans. J Neurophysiol 2021; 126:181-194. [PMID: 34133230 DOI: 10.1152/jn.00027.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The use of transcranial magnetic stimulation to assess the excitability of the central nervous system to further understand the neural control of human movement is expansive. The majority of the work performed to-date has assessed corticospinal excitability either at rest or during relatively simple isometric contractions. The results from this work are not easily extrapolated to rhythmic, dynamic motor outputs, given that corticospinal excitability is task-, phase-, intensity-, direction-, and muscle-dependent (Power KE, Lockyer EJ, Forman DA, Button DC. Appl Physiol Nutr Metab 43: 1176-1185, 2018). Assessing corticospinal excitability during rhythmic motor output, however, involves technical challenges that are to be overcome, or at the minimum considered, when attempting to design experiments and interpret the physiological relevance of the results. The purpose of this narrative review is to highlight the research examining corticospinal excitability during a rhythmic motor output and, importantly, to provide recommendations regarding the many factors that must be considered when designing and interpreting findings from studies that involve limb movement. To do so, the majority of work described herein refers to work performed using arm cycling (arm pedaling or arm cranking) as a model of a rhythmic motor output used to examine the neural control of human locomotion.
Collapse
Affiliation(s)
- Evan J Lockyer
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Chris T Compton
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Davis A Forman
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Gregory E Pearcey
- Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Shirley Ryan Ability Lab, Chicago, Illinois
| | - Duane C Button
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Kevin E Power
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.,Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| |
Collapse
|
6
|
Proessl F, Beckner ME, Sinnott AM, Eagle SR, LaGoy AD, Conkright WR, Canino MC, Sterczala AJ, Midhe Ramkumar PP, Sciavolino BM, Connaboy C, Ferrarelli F, Germain A, Nindl BC, Flanagan SD. Reliability of corticospinal excitability estimates for the vastus lateralis: Practical considerations for lower limb TMS task selection. Brain Res 2021; 1761:147395. [PMID: 33662340 DOI: 10.1016/j.brainres.2021.147395] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/14/2021] [Accepted: 02/16/2021] [Indexed: 11/29/2022]
Abstract
Transcranial magnetic stimulation (TMS) is increasingly used to examine lower extremity corticospinal excitability (CSE) in clinical and sports research. Because CSE is task-specific, there is growing emphasis on the use of ecological tasks. Nevertheless, the comparative reliability of CSE measurements during established (e.g. knee extensions; KE) and more recent ecological (e.g. squats; SQT) lower extremity tasks has received less attention. The aim of this study was to compare the test-retest reliability of CSE, force, and muscle activity (EMG) during isometric SQT and KE. 19 right-footed men (age: 25 ± 5 yrs) with similar fitness and body composition performed SQT (N = 7) or KE (N = 12) on two consecutive days. Force and EMG were recorded during maximum voluntary isometric contractions (MVC). Corticospinal excitability was determined in the dominant leg during light (15% MVC) contractions based on motor evoked potential (MEP) stimulus-response-curves (SRC). Test-retest reliability, absolute agreement, and consistency were determined for force, EMG, and SRC MEP maximum (MEPMAX) and rising phase midpoint (V50). As a secondary analysis, all outcomes were compared between groups with mixed-methods ANCOVAs (Task × Time, covariate: body-fat-percentage). Compared with SQT, KE displayed better test-retest reliability and agreement for MEPMAX whereas V50, force, and EMG were similarly reliable. Force (p = 0.01) and MEPMAX (p = 0.02) were also greater during KE despite a similar V50 (p = 0.11). Differences in test-retest reliability, absolute agreement, and between-group comparisons highlight the need to carefully select lower limb TMS assessment tasks and encourage future efforts to balance ecological validity with statistical sensitivity.
Collapse
Affiliation(s)
- F Proessl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - M E Beckner
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - A M Sinnott
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - S R Eagle
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - A D LaGoy
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA; Department of Psychiatry, University of Pittsburgh Medical School, Pittsburgh, PA, USA
| | - W R Conkright
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - M C Canino
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - A J Sterczala
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - P P Midhe Ramkumar
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - B M Sciavolino
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - C Connaboy
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - F Ferrarelli
- Department of Psychiatry, University of Pittsburgh Medical School, Pittsburgh, PA, USA
| | - A Germain
- Department of Psychiatry, University of Pittsburgh Medical School, Pittsburgh, PA, USA
| | - B C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA
| | - S D Flanagan
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
7
|
Botzheim L, Laczko J, Torricelli D, Mravcsik M, Pons JL, Oliveira Barroso F. Effects of gravity and kinematic constraints on muscle synergies in arm cycling. J Neurophysiol 2021; 125:1367-1381. [PMID: 33534650 DOI: 10.1152/jn.00415.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Arm cycling is a bimanual motor task used in medical rehabilitation and in sports training. Understanding how muscle coordination changes across different biomechanical constraints in arm cycling is a step toward improved rehabilitation approaches. This exploratory study aims to get new insights on motor control during arm cycling. To achieve our main goal, we used the muscle synergies analysis to test three hypotheses: 1) body position with respect to gravity (sitting and supine) has an effect on muscle synergies; 2) the movement size (crank length) has an effect on the synergistic behavior; 3) the bimanual cranking mode (asynchronous and synchronous) requires different synergistic control. Thirteen able-bodied volunteers performed arm cranking on a custom-made device with unconnected cranks, which allowed testing three different conditions: body position (sitting vs. supine), crank length (10 cm vs. 15 cm), and cranking mode (synchronous vs. asynchronous). For each of the eight possible combinations, subjects cycled for 30 s while electromyography of eight muscles (four from each arm) were recorded: biceps brachii, triceps brachii, anterior deltoid, and posterior deltoid. Muscle synergies in this eight-dimensional muscle space were extracted by nonnegative matrix factorization. Four synergies accounted for over 90% of muscle activation variances in all conditions. Results showed that synergies were affected by body position and cranking mode but practically unaffected by movement size. These results suggest that the central nervous system may employ different motor control strategies in response to external constraints such as cranking mode and body position during arm cycling.NEW & NOTEWORTHY Recent studies analyzed muscle synergies in lower limb cycling. Here, we examine upper limb cycling and specifically the effect of body position with respect to gravity, movement size, and cranking mode on muscle coordination during arm cranking tasks. We show that altered body position and cranking mode affects modular organization of muscle activities. To our knowledge, this is the first study assessing motor control through muscle synergies framework during upper limb cycling with different constraints.
Collapse
Affiliation(s)
- Lilla Botzheim
- Department of Information Technology and Biorobotics, Institute of Mathematics and Informatics, Faculty of Sciences, University of Pecs, Pecs, Hungary.,Neurorehabilitation and Motor Control Research Group, Department of Computational Sciences, Wigner Research Centre for Physics, Budapest, Hungary
| | - Jozsef Laczko
- Department of Information Technology and Biorobotics, Institute of Mathematics and Informatics, Faculty of Sciences, University of Pecs, Pecs, Hungary.,Neurorehabilitation and Motor Control Research Group, Department of Computational Sciences, Wigner Research Centre for Physics, Budapest, Hungary.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Diego Torricelli
- Neural Rehabilitation Group, Cajal Institute, Spanish National Research Council, Madrid, Spain
| | - Mariann Mravcsik
- Department of Information Technology and Biorobotics, Institute of Mathematics and Informatics, Faculty of Sciences, University of Pecs, Pecs, Hungary.,Neurorehabilitation and Motor Control Research Group, Department of Computational Sciences, Wigner Research Centre for Physics, Budapest, Hungary
| | - Jose L Pons
- Neural Rehabilitation Group, Cajal Institute, Spanish National Research Council, Madrid, Spain.,Legs & Walking AbilityLab, Shirley Ryan AbilityLab, Chicago, Illinois.,Department of Biomedical Engineering and Mechanical Engineering, McCormick School of Engineering, Northwestern University, Chicago, Illinois.,Department of Physical Medicine and Rehabilitation, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Filipe Oliveira Barroso
- Neural Rehabilitation Group, Cajal Institute, Spanish National Research Council, Madrid, Spain
| |
Collapse
|
8
|
Mravcsik M, Botzheim L, Zentai N, Piovesan D, Laczko J. The Effect of Crank Resistance on Arm Configuration and Muscle Activation Variances in Arm Cycling Movements. J Hum Kinet 2021; 76:175-189. [PMID: 33603933 PMCID: PMC7877280 DOI: 10.2478/hukin-2021-0053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Arm cycling on an ergometer is common in sports training and rehabilitation protocols. The hand movement is constrained along a circular path, and the user is working against a resistance, maintaining a cadence. Even if the desired hand trajectory is given, there is the flexibility to choose patterns of joint coordination and muscle activation, given the kinematic redundancy of the upper limb. With changing external load, motor noise and changing joint stiffness may affect the pose of the arm even though the endpoint trajectory is unchanged. The objective of this study was to examine how the crank resistance influences the variances of joint configuration and muscle activation. Fifteen healthy participants performed arm cranking on an arm-cycle ergometer both unimanually and bimanually with a cadence of 60 rpm against three crank resistances. Joint configuration was represented in a 3-dimensional joint space defined by inter-segmental joint angles, while muscle activation in a 4-dimensional "muscle activation space" defined by EMGs of 4 arm muscles. Joint configuration variance in the course of arm cranking was not affected by crank resistance, whereas muscle activation variance was proportional to the square of muscle activation. The shape of the variance time profiles for both joint configuration and muscle activation was not affected by crank resistance. Contrary to the prevailing assumption that an increased motor noise would affect the variance of auxiliary movements, the influence of noise doesn't appear at the joint configuration level even when the system is redundant. Our results suggest the separation of kinematic- and force-control, via mechanisms that are compensating for dynamic nonlinearities. Arm cranking may be suitable when the aim is to perform training under different load conditions, preserving stable and secure control of joint movements and muscle activations.
Collapse
Affiliation(s)
- Mariann Mravcsik
- Department of Computational Sciences, Wigner Research Centre for Physics, Budapest, H-1121Hungary
- Department of Information Technology and Biorobotics, Faculty of Sciences, University of Pécs, H-7624Hungary
| | - Lilla Botzheim
- Department of Computational Sciences, Wigner Research Centre for Physics, Budapest, H-1121Hungary
- Department of Information Technology and Biorobotics, Faculty of Sciences, University of Pécs, H-7624Hungary
| | - Norbert Zentai
- Department of Information Technology and Biorobotics, Faculty of Sciences, University of Pécs, H-7624Hungary
| | - Davide Piovesan
- Gannon University, Department of Biomedical, Industrial and Systems Engineering, EriePA16501. USA
| | - Jozsef Laczko
- Department of Computational Sciences, Wigner Research Centre for Physics, Budapest, H-1121Hungary
- Department of Information Technology and Biorobotics, Faculty of Sciences, University of Pécs, H-7624Hungary
- Department of Physiology, Feinberg School of Medicine Northwestern University, ChicagoIL6061. USA
| |
Collapse
|
9
|
Lockyer EJ, Soran N, Power KE. Modulation of Corticospinal Excitability with Contralateral Arm Cycling. Neuroscience 2020; 449:88-98. [DOI: 10.1016/j.neuroscience.2020.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 09/30/2020] [Accepted: 10/01/2020] [Indexed: 01/07/2023]
|
10
|
Chaytor CP, Forman D, Byrne J, Loucks-Atkinson A, Power KE. Changes in muscle activity during the flexion and extension phases of arm cycling as an effect of power output are muscle-specific. PeerJ 2020; 8:e9759. [PMID: 32983635 PMCID: PMC7500348 DOI: 10.7717/peerj.9759] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/28/2020] [Indexed: 01/08/2023] Open
Abstract
Arm cycling is commonly used in rehabilitation settings for individuals with motor impairments in an attempt to facilitate neural plasticity, potentially leading to enhanced motor function in the affected limb(s). Studies examining the neural control of arm cycling, however, typically cycle using a set cadence and power output. Given the importance of motor output intensity, typically represented by the amplitude of electromyographic (EMG) activity, on neural excitability, surprisingly little is known about how arm muscle activity is modulated using relative workloads. Thus, the objective of this study was to characterize arm muscle activity during arm cycling at different relative workloads. Participants (n = 11) first completed a 10-second maximal arm ergometry sprint to determine peak power output (PPO) followed by 11 randomized trials of 20-second arm cycling bouts ranging from 5–50% of PPO (5% increments) and a standard 25 W workload. All submaximal trials were completed at 60 rpm. Integrated EMG amplitude (iEMG) was assessed from the biceps brachii, brachioradialis, triceps brachii, flexor carpi radialis, extensor carpi radialis and anterior deltoid of the dominant arm. Arm cycling was separated into two phases, flexion and extension, relative to the elbow joint for all comparisons. As expected, iEMG amplitude increased during both phases of cycling for all muscles examined. With the exception of the triceps brachii and extensor carpi radialis, iEMG amplitudes differed between the flexion and extension phases. Finally, there was a linear relationship between iEMG amplitude and the %PPO for all muscles during both elbow flexion and extension.
Collapse
Affiliation(s)
- Carla P Chaytor
- Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Davis Forman
- Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Jeannette Byrne
- Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Angela Loucks-Atkinson
- Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Kevin E Power
- Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| |
Collapse
|
11
|
Freely Chosen Cadence During Cycling Attenuates Intracortical Inhibition and Increases Intracortical Facilitation Compared to a Similar Fixed Cadence. Neuroscience 2020; 441:93-101. [PMID: 32590040 DOI: 10.1016/j.neuroscience.2020.06.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 11/20/2022]
Abstract
In contrast to other rhythmic tasks such as running, the preferred movement rate in cycling does not minimize energy consumption. It is possible that neurophysiological mechanisms contribute to the choice of cadence, however this phenomenon is not well understood. Eleven participants cycled at a fixed workload of 125 W and different cadences including a freely chosen cadence (FCC, ∼72), and fixed cadences of 70, 80, 90 and 100 revolutions per minute (rpm) during which transcranial magnetic stimulation (TMS) was used to measure short interval intracortical inhibition (SICI) and intracortical facilitation (ICF). There was a significant increase in SICI at 70 (P = 0.004), 80 (P = 0.008) and 100 rpm (P = 0.041) compared to FCC. ICF was significantly reduced at 70 rpm compared to FCC (P = 0.04). Inhibition-excitation ratio (SICI divided by ICF) declined (P = 0.014) with an increase in cadence. The results demonstrate that SICI is attenuated during FCC compared to fixed cadences. The outcomes suggest that the attenuation of intracortical inhibition and augmentation of ICF may be a contributing factor for FCC.
Collapse
|
12
|
Clos P, Garnier Y, Martin A, Lepers R. Corticospinal excitability is altered similarly following concentric and eccentric maximal contractions. Eur J Appl Physiol 2020; 120:1457-1469. [PMID: 32347373 DOI: 10.1007/s00421-020-04377-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/13/2020] [Indexed: 01/24/2023]
Abstract
PURPOSE To examine corticospinal excitability and neuromuscular function following the completion of eccentric (ECC) or concentric (CON) maximal exercises of same mechanical work. METHODS Ten males (29.9 ± 11.8 years) performed maximal isokinetic knee extensor contractions in four experimental sessions. The two first sessions (one in ECC and one in CON) ended with a dynamic peak torque loss of 20%. The work completed in each contraction type was then achieved in the other contraction type. Neuromuscular function- maximal voluntary isometric contraction (MVIC), voluntary activation level (VAL), potentiated doublet (Dt), M-wave- and corticospinal excitability- motor evoked potential (MEP) amplitude and silent period (SP)-were assessed in the vastus lateralis (VL) and rectus femoris (RF) muscles at 20% MVIC before and immediately after exercise. RESULTS To lose 20% of dynamic peak torque subjects performed 1.8 times more work in ECC than CON (P = 0.03), inducing a non-different decline in MVIC (P = 0.15). VAL dropped after the ECC sessions only (- 8.5 ± 6.7%; all P < 0.027). Only, the CON session featuring the greatest work affected Dt amplitude (- 9.4 ± 23.8%; P = 0.047). In both muscles, MEP amplitude decreased (all P < 0.001) and MEP SP stayed constant (all P > 0.45), irrespective of contraction type (all P > 0.15). CONCLUSION Same-work maximal ECC and CON exercises induced similar fatigue level but from different origins (preferentially central for ECC vs peripheral for CON). Yet, net corticospinal excitability did not depend on contraction type.
Collapse
Affiliation(s)
- Pierre Clos
- INSERM UMR1093-CAPS, Université Bourgogne Franche-Comté, UFR des Sciences du Sport, 21000, Dijon, France.
| | - Yoann Garnier
- INSERM UMR1093-CAPS, Université Bourgogne Franche-Comté, UFR des Sciences du Sport, 21000, Dijon, France
- Clermont-Auvergne University, AME2P, Clermont-Ferrand, France
| | - Alain Martin
- INSERM UMR1093-CAPS, Université Bourgogne Franche-Comté, UFR des Sciences du Sport, 21000, Dijon, France
| | - Romuald Lepers
- INSERM UMR1093-CAPS, Université Bourgogne Franche-Comté, UFR des Sciences du Sport, 21000, Dijon, France
| |
Collapse
|
13
|
Nippard AP, Lockyer EJ, Button DC, Power KE. Corticospinal excitability to the biceps and triceps brachii during forward and backward arm cycling is direction- and phase-dependent. Appl Physiol Nutr Metab 2020; 45:72-80. [DOI: 10.1139/apnm-2019-0043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The purpose of this study was to evaluate corticospinal excitability to the biceps and triceps brachii during forward (FWD) and backward (BWD) arm cycling. Corticospinal and spinal excitability were assessed using transcranial magnetic stimulation and transmastoid electrical stimulation to elicit motor evoked potentials (MEPs) and cervicomedullary evoked potentials (CMEPs), respectively. MEPs and CMEPs were recorded from the biceps and triceps brachii during FWD and BWD arm cycling at 2 positions, 6 and 12 o’clock. The 6 o’clock position corresponded to mid-elbow flexion and extension during FWD and BWD cycling, respectively, while 12 o’clock corresponded to mid-elbow extension and flexion during FWD and BWD cycling, respectively. During the flexion phase, MEP and CMEP amplitudes of the biceps brachii were higher during FWD cycling. However, during the extension phase, MEP and CMEP amplitudes were higher during BWD cycling. For the triceps brachii, MEP amplitudes were higher during FWD cycling regardless of phase. However, CMEP amplitudes were phase-dependent. During the flexion phase, CMEPs of the triceps brachii were higher during FWD cycling compared with BWD, but during the extension phase CMEPs were higher during BWD cycling compared with FWD. The data suggest that corticospinal and spinal excitability to the biceps brachii is phase- and direction-dependent. In the triceps brachii, spinal, but not corticospinal, excitability is phase-dependent when comparing FWD and BWD cycling. Novelty This is the first study to assess corticospinal excitability during FWD and BWD locomotor output. Corticospinal excitability during arm cycling depends on the direction, phase, and muscle being assessed.
Collapse
Affiliation(s)
- Anna. P. Nippard
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
| | - Evan. J. Lockyer
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
| | - Duane. C. Button
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
| | - Kevin. E. Power
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
| |
Collapse
|
14
|
Lockyer EJ, Hosel K, Nippard AP, Button DC, Power KE. Corticospinal-Evoked Responses from the Biceps Brachii during Arm Cycling across Multiple Power Outputs. Brain Sci 2019; 9:brainsci9080205. [PMID: 31430879 PMCID: PMC6721304 DOI: 10.3390/brainsci9080205] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/13/2019] [Accepted: 08/15/2019] [Indexed: 11/30/2022] Open
Abstract
Background: We examined corticospinal and spinal excitability across multiple power outputs during arm cycling using a weak and strong stimulus intensity. Methods: We elicited motor evoked potentials (MEPs) and cervicomedullary motor evoked potentials (CMEPs) in the biceps brachii using magnetic stimulation over the motor cortex and electrical stimulation of corticospinal axons during arm cycling at six different power outputs (i.e., 25, 50, 100, 150, 200 and 250 W) and two stimulation intensities (i.e., weak vs. strong). Results: In general, biceps brachii MEP and CMEP amplitudes (normalized to maximal M-wave (Mmax)) followed a similar pattern of modulation with increases in cycling intensity at both stimulation strengths. Specifically, MEP and CMEP amplitudes increased up until ~150 W and ~100 W when the weak and strong stimulations were used, respectively. Further increases in cycling intensity revealed no changes on MEP or CMEP amplitudes for either stimulation strength. Conclusions: In general, MEPs and CMEPs changed in a similar manner, suggesting that increases and subsequent plateaus in overall excitability are likely mediated by spinal factors. Interestingly, however, MEP amplitudes were disproportionately larger than CMEP amplitudes as power output increased, despite being initially matched in amplitude, particularly with strong stimulation. This suggests that supraspinal excitability is enhanced to a larger degree than spinal excitability as the power output of arm cycling increases.
Collapse
Affiliation(s)
- Evan J Lockyer
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
| | - Katarina Hosel
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
| | - Anna P Nippard
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
| | - Duane C Button
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
| | - Kevin E Power
- Human Neurophysiology Lab, School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada.
| |
Collapse
|
15
|
Alcock LR, Spence AJ, Lockyer EJ, Button DC, Power KE. Short-interval intracortical inhibition to the biceps brachii is present during arm cycling but is not different than a position- and intensity-matched tonic contraction. Exp Brain Res 2019; 237:2145-2154. [DOI: 10.1007/s00221-019-05579-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 06/08/2019] [Indexed: 10/26/2022]
|
16
|
Corticospinal Excitability to the Biceps Brachii is Not Different When Arm Cycling at a Self-Selected or Fixed Cadence. Brain Sci 2019; 9:brainsci9020041. [PMID: 30769825 PMCID: PMC6406314 DOI: 10.3390/brainsci9020041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 02/11/2019] [Accepted: 02/12/2019] [Indexed: 11/17/2022] Open
Abstract
Background: The present study compared corticospinal excitability to the biceps brachii muscle during arm cycling at a self-selected and a fixed cadence (SSC and FC, respectively). We hypothesized that corticospinal excitability would not be different between the two conditions. Methods: The SSC was initially performed and the cycling cadence was recorded every 5 s for one minute. The average cadence of the SSC cycling trial was then used as a target for the FC of cycling that the participants were instructed to maintain. The motor evoked potentials (MEPs) elicited via transcranial magnetic stimulation (TMS) of the motor cortex were recorded from the biceps brachii during each trial of SSC and FC arm cycling. Results: Corticospinal excitability, as assessed via normalized MEP amplitudes (MEPs were made relative to a maximal compound muscle action potential), was not different between groups. Conclusions: Focusing on maintaining a fixed cadence during arm cycling does not influence corticospinal excitability, as assessed via TMS-evoked MEPs.
Collapse
|