Related Experiment Video
Updated: Apr 23, 2026
Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Task and intensity alters the RMS proportionality ratio in the triceps surae
Nick Ball1, Joanna Clare Scurr2
1University of Canberra, Discipline of Sport and Exercise Science, Bruce, Canberra, ACT, Atblralia.
Introduction:
Dynamic movements require synergistic involvement of numerous muscles, whereby different muscular and task demands could alter the ratio of this synergistic activation.
Methods:
Participants completed isometric, isotonic, isokinetic, and squat jump (SJ) tasks. Mean RMS EMG was collected from the medial and lateral gastrocnemius (MG, LG) and soleus (SOL), then pooled, and each muscle's activation was expressed as a percentage of the pooled activation.
Results:
The MG contributed 9-14% more to total muscle activation in isometric and isotonic tasks versus the SJ task. The SOL contributed 8% more to the SJ task compared with the isometric and isotonic tasks. Across all tasks, MG activation was 4.0% greater than SOL and 10.5% greater than LG. SOL activation was 6.5% greater in all tasks compared with LG.
Conclusions:
Task and intensity influences the ratio of activation in the triceps surae.
