Document Type
Journal Article
Publication Title
Scandinavian Journal of Medicine and Science in Sports
Volume
31
Issue
3
First Page
597
Last Page
609
Publisher
Wiley
School
School of Medical and Health Sciences / Centre for Exercise and Sports Science Research
RAS ID
32674
Funders
Japan Society for the Promotion of Science
Abstract
© 2020 The Authors. Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd This study tested the hypothesis that the magnitude of rectus femoris (RF) damage and the repeated bout effect (RBE) would be greater after knee extensor eccentric exercise performed in a supine (long RF lengths) than a sitting (short RF lengths) position, and the muscle length effects would be more prominent at the proximal than distal RF. Young untrained men were placed to one of the two groups (n = 14 per group). S group performed the knee extensor eccentric exercise in the sitting position for the first bout and the supine position for the second bout, and L group performed the exercise in the supine position for two bouts, with 4 weeks between bouts. Dependent variables included evoked and maximal voluntary isometric contraction (MVC) torque, electromyography (EMG) during MVC, muscle soreness, and shear modulus, which were measured before and 1-3 days after each exercise bout. After the first bout, L group in comparison with S group showed greater (P < .05) changes in hip flexor MVC torque (average of 1-3 days post-exercise: −11.1 ± 9.4% vs −5.0 ± 7.5%), proximal RF EMG (−22.4 ± 16% vs −9.0 ± 21.9%), and proximal RF shear modulus (33.2 ± 22.8% vs 16.9 ± 13.5%). No significant differences between groups were evident for any of other variables after the first bout including knee extensor MVC torque, and for the changes in all variables after the second bout. These results supported the hypothesis that RF damage would be greater for the spine than sitting position especially at the proximal region, but did not support the hypothesis about the RBE.
DOI
10.1111/sms.13890
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Comments
Ema, R., Nosaka, K., Kawashima, R., Kanda, A., Ikeda, K., & Akagi, R. (2021). Muscle length influence on rectus femoris damage and protective effect in knee extensor eccentric exercise. Scandinavian Journal of Medicine & Science in Sports, 31(3), 597-609. https://doi.org/10.1111/sms.13890