Work

Effects of inter-set stretching on acute fatigue-related changes in vastus lateralis muscle architecture and knee extensor torque

Year: 2026

Type: article

Abstract: Background: Muscle fatigue, characterized by a reduction in force or torque production during resistance training, is often associated with changes in muscle architecture, such as fascicle length and pennation angle, which influence torque-generating capacity. Inter-set static stretching has been proposed as a time-efficient method to modulate these parameters, but its acute effects on muscle fatigue and architecture remain unclear. Objective: This study aimed to investigate the impact of inter-set stretching on fatigue-induced changes in fascicle length, pennation angle, and knee extension torque. Methods: Fifteen men performed 4 × 10 maximal isokinetic knee extensions. One limb underwent 30-second inter-set stretching, while the other limb recovered passively. Vastus lateralis muscle architecture (pennation angle and fascicle length; proximal and distal regions) and knee extensor torque (peak torque and peak torque angle; concentric and eccentric contractions) were measured and compared between protocols. Results: Inferential tests revealed no significant differences between protocols for torque or muscle architecture. However, effect size analysis indicated that the inter-set stretching protocol increased fascicle length in the distal [1.64 (0.8; 2.2)] and proximal [0.52 (-0.0; 1.0)] regions and reduced concentric peak torque fatigue [0.86 (0.2; 1.3)]. Conversely, the passive rest protocol showed a greater proximal pennation angle [-0.81 (-1.4; -0.1)]. Conclusion: Short-duration inter-set stretching can attenuate fatigue induced by resistance exercise, with muscle architecture changes associated with these responses. Clinically, incorporating a few sets of inter-set stretching lasting 30 seconds may provide practical benefits.

Source: Muscles Ligaments and Tendons Journal

DOI: 10.32098/mltj_2026_6516

Authors: Gustavo Henrique Halmenschlager, Liliam Fernandes de Oliveira, Thiago Torres da Matta

Institution: Universidade Federal do Rio de Janeiro

Topic: Sports Performance and Training

Subfield: Orthopedics and Sports Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Funders: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Financiadora de Estudos e Projetos

OpenAlex ID: W7147098233