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Stuckenschneider T, Koschate J, Dunker E, Reeck N, Hackbarth M, Hellmers S, Kwiecien R, Lau S, Levke Brütt A, Hein A, Zieschang T. Sentinel fall presenting to the emergency department (SeFallED) - protocol of a complex study including long-term observation of functional trajectories after a fall, exploration of specific fall risk factors, and patients' views on falls prevention. BMC Geriatr 2022; 22:594. [PMID: 35850739 PMCID: PMC9289928 DOI: 10.1186/s12877-022-03261-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 07/03/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Falls are a leading cause for emergency department (ED) visits in older adults. As a fall is associated with a high risk of functional decline and further falls and many falls do not receive medical attention, the ED is ideal to initiate secondary prevention, an opportunity generally not taken. Data on trajectories to identify patients, who would profit the most form early intervention and to examine the impact of a fall event, are lacking. To tailor interventions to the individual's needs and preferences, and to address the whole scope of fall risks, we developed this longitudinal study using an extensive assessment battery including dynamic balance and aerobic fitness, but also sensor-based data. Additionally, participative research will contribute valuable qualitative data, and machine learning will be used to identify trips, slips, and falls in sensor data during daily life. METHODS This is a mixed-methods study consisting of four parts: (1) an observational prospective study, (2) a randomized controlled trial (RCT) to explore whether a diagnostic to measure reactive dynamic balance influences fall risk, (3) machine learning approaches and (4) a qualitative study to explore patients' and their caregivers' views. We will target a sample size of 450 adults of 60 years and older, who presented to the ED of the Klinikum Oldenburg after a fall and are not hospitalized. The participants will be followed up over 24 months (within four weeks after the ED, after 6, 12 and 24 months). We will assess functional abilities, fall risk factors, participation, quality of life, falls incidence, and physical activity using validated instruments, including sensor-data. Additionally, two thirds of the patients will undergo intensive testing in the gait laboratory and 72 participants will partake in focus group interviews. DISCUSSION The results of the SeFallED study will be used to identify risk factors with high predictive value for functional outcome after a sentinel fall. This will help to (1) establish a protocol adapted to the situation in the ED to identify patients at risk and (2) to initiate an appropriate care pathway, which will be developed based on the results of this study. TRIAL REGISTRATION DRKS (Deutsches Register für klinische Studien, DRKS00025949 ). Prospectively registered on 4th November, 2021.
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Affiliation(s)
- Tim Stuckenschneider
- Department for Health Services Research, Geriatric Medicine, School of Medicine and Health Sciences, Carl Von Ossietzky University, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
| | - Jessica Koschate
- Department for Health Services Research, Geriatric Medicine, School of Medicine and Health Sciences, Carl Von Ossietzky University, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
| | - Ellen Dunker
- Department for Health Services Research, Geriatric Medicine, School of Medicine and Health Sciences, Carl Von Ossietzky University, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
| | - Nadja Reeck
- Department of Health Services Research, Junior Research Group for Rehabilitation Sciences, School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Michel Hackbarth
- Department for Health Services Research, Geriatric Medicine, School of Medicine and Health Sciences, Carl Von Ossietzky University, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
| | - Sandra Hellmers
- Department for Health Assistance Systems and Medical Device Technology, Services Research, School of Medicine and Health Sciences, Carl Von Ossietzky University, Oldenburg, Germany
| | - Robert Kwiecien
- Institute of Biostatistics and Clinical Research, University of Muenster, Münster, Germany
| | - Sandra Lau
- Department for Health Services Research, Geriatric Medicine, School of Medicine and Health Sciences, Carl Von Ossietzky University, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany
| | - Anna Levke Brütt
- Department of Health Services Research, Junior Research Group for Rehabilitation Sciences, School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Andreas Hein
- Department for Health Assistance Systems and Medical Device Technology, Services Research, School of Medicine and Health Sciences, Carl Von Ossietzky University, Oldenburg, Germany
| | - Tania Zieschang
- Department for Health Services Research, Geriatric Medicine, School of Medicine and Health Sciences, Carl Von Ossietzky University, Ammerländer Heerstraße 114-118, 26129, Oldenburg, Germany.
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Hoffmann U, Faber F, Drescher U, Koschate J. Cardiorespiratory kinetics in exercise physiology: estimates and predictions using randomized changes in work rate. Eur J Appl Physiol 2021; 122:717-726. [PMID: 34962595 PMCID: PMC8854137 DOI: 10.1007/s00421-021-04878-z] [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] [Received: 07/05/2021] [Accepted: 12/16/2021] [Indexed: 11/18/2022]
Abstract
Purpose Kinetics of cardiorespiratory parameters (CRP) in response to work rate (WR) changes are evaluated by pseudo-random binary sequences (PRBS testing). In this study, two algorithms were applied to convert responses from PRBS testing into appropriate impulse responses to predict steady states values and responses to incremental increases in exercise intensity. Methods 13 individuals (age: 41 ± 9 years, BMI: 23.8 ± 3.7 kg m−2), completing an exercise test protocol, comprising a section of randomized changes of 30 W and 80 W (PRBS), two phases of constant WR at 30 W and 80 W and incremental WR until subjective fatigue, were included in the analysis. Ventilation (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}_{{\text{E}}}$$\end{document}V˙E), O2 uptake (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2), CO2 output (\documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{CO}}_{2}$$\end{document}V˙CO2) and heart rate (HR) were monitored. Impulse responses were calculated in the time domain and in the frequency domain from the cross-correlations of WR and the respective CRP. Results The algorithm in the time domain allows better prediction for \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 and \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{CO}}_{2}$$\end{document}V˙CO2, whereas for \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}_{{\text{E}}}$$\end{document}V˙E and HR the results were similar for both algorithms. Best predictions were found for \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 and HR with higher (3–4%) 30 W steady states and lower (1–4%) values for 80 W. Tendencies were found in the residuals between predicted and measured data. Conclusion The CRP kinetics, resulting from PRBS testing, are qualified to assess steady states within the applied WR range. Below the ventilatory threshold, \documentclass[12pt]{minimal}
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\begin{document}$$\dot{V}{\text{O}}_{2}$$\end{document}V˙O2 and HR responses to incrementally increasing exercise intensities can be sufficiently predicted.
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Affiliation(s)
- Uwe Hoffmann
- Department of Exercise Physiology, Institute of Exercise Training and Sport Informatics, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany.
| | - Felix Faber
- Department of Exercise Physiology, Institute of Exercise Training and Sport Informatics, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany
| | - Uwe Drescher
- Department of Exercise Physiology, Institute of Exercise Training and Sport Informatics, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933, Cologne, Germany
| | - Jessica Koschate
- Geriatric Medicine, Department for Health Services Research, School of Medicine and Health Sciences, Carl Von Ossietzky University Oldenburg, Ammerlaender Heerstr.140, 26129, Oldenburg, Germany
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Koschate J, Drescher U, Hoffmann U. Confinement, partial sleep deprivation and defined physical activity-influence on cardiorespiratory regulation and capacity. Eur J Appl Physiol 2021; 121:2521-2530. [PMID: 34080066 PMCID: PMC8357778 DOI: 10.1007/s00421-021-04719-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 05/13/2021] [Indexed: 11/01/2022]
Abstract
INTRODUCTION Adequate cardiorespiratory fitness is of utmost importance during spaceflight and should be assessable via moderate work rate intensities, e.g., using kinetics parameters. The combination of restricted sleep, and defined physical exercise during a 45-day simulated space mission is expected to slow heart rate (HR) kinetics without changes in oxygen uptake ([Formula: see text]) kinetics. METHODS Overall, 14 crew members (9 males, 5 females, 37 ± 7 yrs, 23.4 ± 3.5 kg m-2) simulated a 45-d-mission to an asteroid. During the mission, the sleep schedule included 5 nights of 5 h and 2 nights of 8 h sleep. The crew members were tested on a cycle ergometer, using pseudo-random binary sequences, changing between 30 and 80 W on day 8 before (MD-8), day 22 (MD22) and 42 (MD42) after the beginning and day 4 (MD + 4) following the end of the mission. Kinetics information was assessed using the maxima of cross-correlation functions (CCFmax). Higher CCFmax indicates faster responses. RESULTS CCFmax(HR) was significantly (p = 0.008) slower at MD-8 (0.30 ± 0.06) compared with MD22 (0.36 ± 0.06), MD42 (0.38 ± 0.06) and MD + 4 (0.35 ± 0.06). Mean HR values during the different work rate steps were higher at MD-8 and MD + 4 compared to MD22 and MD42 (p < 0.001). DISCUSSION The physical training during the mission accelerated HR kinetics, but had no impact on mean HR values post mission. Thus, HR kinetics seem to be sensitive to changes in cardiorespiratory fitness and may be a valuable parameter to monitor fitness. Kinetics and capacities adapt independently in response to confinement in combination with defined physical activity and sleep.
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Affiliation(s)
- Jessica Koschate
- Geriatric Medicine, Department for Health Services Research, School of Medicine and Health Sciences, Carl Von Ossietzky University Oldenburg, Ammerländer Heerstr. 140, 26129 Oldenburg, Germany
| | - Uwe Drescher
- German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany
| | - Uwe Hoffmann
- Institute of Exercise Training and Sport Informatics, Exercise Physiology, German Sport University Cologne, Am Sportpark Müngersdorf 6, 50933 Cologne, Germany
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Combret Y, Medrinal C, Prieur G, Robledo Quesada A, Gillot T, Gravier FE, Bonnevie T, Lamia B, Le Roux P, Reychler G. Oxygen uptake kinetics during treadmill walking in adolescents with clinically stable cystic fibrosis. Physiother Theory Pract 2021; 38:1389-1397. [PMID: 33390080 DOI: 10.1080/09593985.2020.1868029] [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] [Indexed: 12/14/2022]
Abstract
Background: Oxygen uptake (V̇O2) kinetics have been shown to be slowed in adolescents with cystic fibrosis (CF) during heavy-intensity cycling and maximal exercise testing.Objectives: This study investigated V̇O2 kinetics in adolescents with CF compared to control adolescents (CON) during a treadmill-walking exercise.Methods: Eight adolescents with CF and mild-to-moderate pulmonary obstruction (5 girls; 13.1 ± 2.5 years; FEV1 67.8 ± 21.4%) and 18 CON adolescents (10 girls; 13.8 ± 1.8 years) were recruited. Pulmonary gas exchange and ventilation were measured during a single transition of 10 min of treadmill walking and a 5 min seated recovery period. Participant's walking speed was determined during a one-minute self-paced walking task along a 50-m corridor. A six-parameter, non-linear regression model was used to describe the changes in V̇O2 function during the treadmill walking and recovery, with monoexponential curve fitting used to describe the mean response time (MRT1) at the onset of exercise, and the half-life (T1/2V̇O2) at the offset of exercise. V̇O2 baseline and amplitude, minute ventilation and respiratory equivalents were recorded.Results: V̇O2 kinetics were slower in CF group compared to CON group during the treadmill walking with a greater MRT1 (32 ± 14 s vs 21 ± 16 s; p = .04, effect size = 0.75). The T1/2V̇O2 was prolonged during recovery in CF group compared to CON group (86 ± 24 s vs 56 ± 22 s; p = .04, effect size = 1.31). The mean VE/V̇CO2 during exercise was the only parameter significantly greater in CF group compared to CON group (32.9 ± 2.3 vs 29.0 ± 2.4; p < .01, effect size = 1.66). Conclusion: V̇O2 kinetics were found to be slowed in adolescents with CF during treadmill walking.
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Affiliation(s)
- Yann Combret
- Physiotherapy Department, Le Havre Hospital, Montivilliers, France.,Institut De Recherche Et d'Expérimentation Clinique (IREC), Pôle De Pneumologie, ORL and Dermatologie, Université Catholique De Louvain, Brussels, Belgium
| | - Clément Medrinal
- Physiotherapy Department, Le Havre Hospital, Montivilliers, France.,Erphan, Paris-Saclay University, UVSQ, Versailles, France.,Saint Michel School of Physiotherapy, Paris, France
| | - Guillaume Prieur
- Physiotherapy Department, Le Havre Hospital, Montivilliers, France.,Institut De Recherche Et d'Expérimentation Clinique (IREC), Pôle De Pneumologie, ORL and Dermatologie, Université Catholique De Louvain, Brussels, Belgium.,UPRES EA3830 - GRHV, Normandie University, UNIROUEN, Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
| | | | - Timothée Gillot
- Cetaps, EA3832, Rouen University, Mont Saint Aignan, France.,School of Physiotherapy, Rouen University Hospital, Rouen, France
| | - Francis-Edouard Gravier
- UPRES EA3830 - GRHV, Normandie University, UNIROUEN, Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France.,ADIR Association, Rouen University Hospital, Bois-Guillaume, France
| | - Tristan Bonnevie
- UPRES EA3830 - GRHV, Normandie University, UNIROUEN, Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France.,ADIR Association, Rouen University Hospital, Bois-Guillaume, France
| | - Bouchra Lamia
- UPRES EA3830 - GRHV, Normandie University, UNIROUEN, Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France.,Pulmonology Department, Le Havre Hospital, Montivilliers, France.,Intensive Care Unit, Respiratory Department, Rouen University Hospital, Rouen, France
| | - Pascal Le Roux
- Pediatric Department, Le Havre Hospital, Montivilliers, France
| | - Grégory Reychler
- Institut De Recherche Et d'Expérimentation Clinique (IREC), Pôle De Pneumologie, ORL and Dermatologie, Université Catholique De Louvain, Brussels, Belgium.,Department of Physical Medicine and Rehabilitation, Saint-Luc University Clinics, Brussels, Belgium
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Beltrame T, Gois MO, Hoffmann U, Koschate J, Hughson RL, Moraes Frade MC, Linares SN, da Silva Torres R, Catai AM. Relationship between maximal aerobic power with aerobic fitness as a function of signal-to-noise ratio. J Appl Physiol (1985) 2020; 129:522-532. [PMID: 32730176 DOI: 10.1152/japplphysiol.00310.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Efforts to better understand cardiorespiratory health are relevant for the future development of optimized physical activity programs. We aimed to explore the impact of the signal quality on the expected associations between the ability of the aerobic system in supplying energy as fast as possible during moderate exercise transitions with its maximum capacity to supply energy during maximal exertion. It was hypothesized that a slower aerobic system response during moderate exercise transitions is associated with a lower maximal aerobic power; however, this relationship relies on the quality of the oxygen uptake data set. Forty-three apparently healthy participants performed a moderate constant work rate (CWR) followed by a pseudorandom binary sequence (PRBS) exercise protocol on a cycle ergometer. Participants also performed a maximum incremental cardiopulmonary exercise testing (CPET). The maximal aerobic power was evaluated by the peak oxygen uptake during the CPET, and the aerobic fitness was estimated from different approaches for oxygen uptake dynamics analysis during the CWR and PRBS protocols at different levels of signal-to-noise ratio. The product moment correlation coefficient was used to evaluate the correlation level between variables. Aerobic fitness was correlated with maximum aerobic power, but this correlation increased as a function of the signal-to-noise ratio. Aerobic fitness is related to maximal aerobic power; however, this association appeared to be highly dependent on the data quality and analysis for aerobic fitness evaluation. Our results show that simpler moderate exercise protocols might be as good as maximal exertion exercise protocols to obtain indexes related to cardiorespiratory health.NEW & NOTEWORTHY Optimized methods for cardiorespiratory health evaluation are of great interest for public health. Moderate exercise protocols might be as good as maximum exertion exercise protocols to evaluate cardiorespiratory health. Pseudorandom or constant workload moderate exercise can be used to evaluate cardiorespiratory health.
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Affiliation(s)
- Thomas Beltrame
- Department of Physical Therapy, Federal University of São Carlos, São Carlos, São Paulo, Brazil.,Universidade Ibirapuera, São Paulo, São Paulo, Brazil
| | - Mariana Oliveira Gois
- Department of Physical Therapy, Federal University of São Carlos, São Carlos, São Paulo, Brazil
| | - Uwe Hoffmann
- German Sport University Cologne, Cologne, Germany
| | - Jessica Koschate
- Geriatric Medicine, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Richard Lee Hughson
- University of Waterloo, Schlegel-University of Waterloo Research Institute for Aging, Waterloo, Ontario, Canada
| | | | | | - Ricardo da Silva Torres
- Department of Information and Communications Technology (ICT) and Natural Sciences, Faculty of Information Technology and Electrical Engineering, NTNU-Norwegian University of Science and Technology, Ålesund, Norway
| | - Aparecida Maria Catai
- Department of Physical Therapy, Federal University of São Carlos, São Carlos, São Paulo, Brazil
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Beltrame T, Villar R, Hughson RL. Sex differences in the oxygen delivery, extraction, and uptake during moderate-walking exercise transition. Appl Physiol Nutr Metab 2017; 42:994-1000. [DOI: 10.1139/apnm-2017-0097] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies in children and older adults demonstrated faster oxygen uptake (V̇O2) kinetics in males compared with females, but young healthy adults have not been studied. We hypothesized that young men would have faster aerobic system dynamics in response to the onset of exercise than women. Interactions between oxygen supply and utilization were characterized by the dynamics of V̇O2, deoxyhemoglobin (HHb), tissue saturation index (TSI), cardiac output (Q̇), and calculated arteriovenous O2 difference (a–vO2diff) in women and men. Eighteen healthy active young women and men (9 of each sex) with similar aerobic fitness levels volunteered for this study. Participants performed an incremental cardiopulmonary treadmill exercise test and 3 moderate-intensity treadmill exercise tests (at 80% V̇O2 of gas exchange threshold). Data related to the moderate exercise were submitted to exponential data modelling to obtain parameters related to the aerobic system dynamics. The time constants of V̇O2, a–vO2diff, HHb, and TSI (30 ± 6, 29 ± 1, 16 ± 1, and 15 ± 2 s, respectively) in women were statistically (p < 0.05) faster than the time constants in men (42 ± 10, 49 ± 21, 19 ± 3, and 20 ± 4 s, respectively). Although Q̇ dynamics were not statistically different (p = 0.06) between groups, there was a trend to slower Q̇ dynamics in men corresponding with the slower V̇O2 kinetics. These results indicated that the peripheral and pulmonary oxygen extraction dynamics were remarkably faster in women. Thus, contrary to the hypothesis, V̇O2 dynamics measured at the mouth at the onset of submaximal treadmill walking were faster in women compared with men.
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Affiliation(s)
- Thomas Beltrame
- Faculty of Applied Health Sciences, University of Waterloo, Waterloo, ON N2L 3G1, Canada
- Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brasilia, Distrito Federal, CEP: 71605-001, Brazil
| | - Rodrigo Villar
- Faculty of Applied Health Sciences, University of Waterloo, Waterloo, ON N2L 3G1, Canada
- Faculty of Health Sciences, Division of Natural Sciences, Franklin Pierce University, Rindge, NH 03461, USA
| | - Richard L. Hughson
- Faculty of Applied Health Sciences, University of Waterloo, Waterloo, ON N2L 3G1, Canada
- Schlegel-University of Waterloo Research Institute for Aging, Waterloo, ON N2J 0E2, Canada
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Beltrame T, Hughson RL. Mean Normalized Gain: A New Method for the Assessment of the Aerobic System Temporal Dynamics during Randomly Varying Exercise in Humans. Front Physiol 2017; 8:504. [PMID: 28769818 PMCID: PMC5513944 DOI: 10.3389/fphys.2017.00504] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Accepted: 06/29/2017] [Indexed: 11/13/2022] Open
Abstract
The temporal dynamics of the oxygen uptake ([Formula: see text]) during moderate exercise has classically been related to physical fitness and a slower [Formula: see text] dynamics was associated with deterioration of physical health. However, methods that better characterize the aerobic system temporal dynamics remain challenging. The purpose of this study was to develop a new method (named mean normalized gain, MNG) to systematically characterize the [Formula: see text] temporal dynamics. Eight healthy, young adults (28 ± 6 years old, 175 ± 7 cm and 79 ± 13 kg) performed multiple pseudorandom binary sequence cycling protocols on different days and time of the day. The MNG was calculated as the normalized amplitude of the [Formula: see text] signal in frequency-domain. The MNG was validated considering the time constant τ obtained from time-domain analysis as reference. The intra-subject consistency of the MNG was checked by testing the same participant on different days and times of the day. The MNG and τ were strongly negatively correlated (r = -0.86 and p = 0.005). The MNG measured on different days and periods of the day was similar between conditions. Calculations for the MNG have inherent filtering characteristics enhancing reliability for the evaluation of the aerobic system temporal dynamics. In conclusion, the present study successfully validated the use of the MNG for aerobic system analysis and as a potential complementary tool to assess changes in physical fitness.
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Affiliation(s)
- Thomas Beltrame
- Department of Kinesiology, University of WaterlooWaterloo, ON, Canada.,Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Brasília, Brazil.,Department of Physiotherapy, Universidade IbirapueraSão Paulo, Brazil
| | - Richard L Hughson
- Department of Kinesiology, University of WaterlooWaterloo, ON, Canada.,Schlegel-University of Waterloo Research Institute for AgingWaterloo, ON, Canada
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