Minimum intensity of daily six eccentric contractions to increase muscle strength and size
Document Type
Journal Article
Publication Title
Scandinavian Journal of Medicine and Science in Sports
Volume
34
Issue
6
PubMed ID
38898582
Publisher
Wiley
School
Centre for Human Performance / School of Medical and Health Sciences
RAS ID
71495
Funders
Descente and Ishimoto Memorial Foundation for the Promotion of Sports Science
Abstract
Our previous study showed that daily six maximal eccentric contractions that were performed 5 days a week for 4 weeks increased maximal voluntary isometric (MVC-ISO), concentric (MVC-CON), and eccentric contraction (MVC-ECC) strength of the elbow flexors and muscle thickness of biceps brachii and brachialis (MT) by 8.3 ± 4.9%, 11.1 ± 7.4%, 13.5 ± 11.5%, and 10.6 ± 5.1%, respectively. In the present study, we tested the hypothesis that the muscle strength and MT would still increase when the training intensity was reduced to 2/3 or 1/3 of the peak MVC-ECC torque. Thirty-six healthy young (19–24 years) adults who had not performed resistance training were placed to three groups (n = 12/group): 2/3MVC or 1/3MVC that performed six eccentric contractions with 2/3 or 1/3 MVC-ECC load using a dumbbell 5 days a week for 4 weeks or control group that did not perform any training. Changes in the MVC-ISO, MVC-CON, MVC-ECC torque, and MT before and after the 4-week period were compared among the groups and with the group of the previous study in which six maximal eccentric contractions were performed 5 days a week for 4 weeks (MVC group; n = 12). The control and 1/3MVC groups showed no significant changes in any measures. Significant (p < 0.05) increases in MVC-ISO (10.3 ± 11.4%), MVC-CON (10.9 ± 9.5%), and MVC-ECC (9.3 ± 8.8%) torque and MT (10.1 ± 9.2%) were observed for the 2/3MVC group. These changes were not significantly different from those of the MVC group. These results suggest that the 2/3-intensity eccentric contractions with a dumbbell are as effective as maximal-intensity isokinetic eccentric contractions to induce muscle adaptations.
DOI
10.1111/sms.14683
Access Rights
subscription content
Comments
Yoshida, R., Murakami, Y., Kasahara, K., Sato, S., Nosaka, K., & Nakamura, M. (2024). Minimum intensity of daily six eccentric contractions to increase muscle strength and size. Scandinavian Journal of Medicine & Science in Sports, 34(6), e14683. https://doi.org/10.1111/sms.14683