Neuromuscular responses to isometric, concentric and eccentric contractions of the knee extensors at the same torque-time integral
Document Type
Journal Article
Publication Title
European journal of applied physiology
Volume
122
First Page
127
Last Page
139
PubMed ID
34591170
Publisher
Springer
School
Centre for Exercise and Sports Science Research / School of Medical and Health Sciences
RAS ID
43276
Abstract
PURPOSE:
The present study compared isometric, concentric and eccentric contractions at the same torque-time integral for changes in neuromuscular fatigue and muscle damage parameters.
METHOD:
Healthy men (18-24 years) were placed to either isometric (ISO), concentric (CONC), or eccentric (ECC) group (n = 11/group) that performed corresponding contractions of the knee extensors to exert the same amount of torque-time integral (24,427 ± 291 Nm·s). Changes in maximal voluntary contraction (MVC) torque, voluntary activation, evoked torque at 10 Hz and 100 Hz and its ratio, M-wave amplitude, and muscle soreness were assessed immediately before and after, 1 h, 1 day and 2 days after each exercise, and were compared among the groups.
RESULTS:
MVC torque decreased immediately after ISO (- 17.0 ± 8.3%), CONC (- 21.7 ± 11.5%) and ECC (- 26.2 ± 15.6%) similarly (p = 0.35), but the decrease sustained longer (p < 0.05) for ECC (2 days post-exercise: - 12.9 ± 14.8%) and ISO (- 5.5 ± 7.9%) than CONC (+ 5.0 ± 11.0%). Muscle soreness developed after ECC (25.1 ± 19.8 mm) and ISO (17.5 ± 21.0 mm) similarly (p = 0.15). Voluntary activation decreased immediately (- 3.7 ± 6.6%) and 1 h post-exercise (- 4.7 ± 7.6%) for all groups similarly. Electrically evoked forces decreased greater immediately (- 30.1 ± 15.6%) and 1 h post-exercise (- 35.0 ± 12.8%) for ECC than others, and the decrease in 10/100 Hz ratio was also greater immediately (- 30.5 ± 12.6%) and 1 h after ECC (- 23.8 ± 10.3%) than others.
CONCLUSION:
ISO, CONC and ECC with the same torque-time integral produced similar neuromuscular fatigue at immediately post-exercise, but the force loss was longer-lasting after ISO and ECC than CONC, and the changes in peripheral fatigue parameters were the greatest after ECC, suggesting greater muscle damage.
DOI
10.1007/s00421-021-04817-y
Access Rights
subscription content
Comments
Royer, N., Nosaka, K., Doguet, V., & Jubeau, M. (2022). Neuromuscular responses to isometric, concentric and eccentric contractions of the knee extensors at the same torque-time integral. European Journal of Applied Physiology, vol. 122, p. 127-139.
https://doi.org/10.1007/s00421-021-04817-y