Differences in triceps surae muscle dynamometry and electromyography between adult males and females

The triceps surae performs vital functions during locomotion and possesses shock-absorbing capacity. The injury rate of the Achilles tendon is higher in males than females. Quantification of the triceps surae muscle force outputs across sexes has not been determined. This study aimed to investigate and quantify sex-related triceps surae isokinetic parameters and activation magnitudes. A repeated-measures comparative design is implemented. A total of 20 males and 20 females joined this study. An isokinetic dynamometer and a synchronized electromyography system were employed to measure isokinetic torque, power, work, and muscle amplitude during the dynamic plantar flexion test. The participants performed 3 trials at 2 knee angles to target the gastrocnemius and soleus. There were sex-related differences in triceps surae performance. Males demonstrated more isokinetic torque, power, and work (P < .05) than females. Males scored more normalized peak torque (49% and 80%) and work (47% and 108%) than females in extended and right-angled knees, respectively. All participants demonstrated improved isokinetic output when the knee was extended rather than flexed. The triceps surae muscle compartments were activated uniformly across sexes (P > .05). Males exerted greater plantar flexion isokinetic parameters than their female counterparts. Males may be more likely to sustain injuries than females due to increased strain on the Achilles tendon caused by greater torque and power output. Such differences may impact athletic performance, injury risk, functional tasks, and job demands. Therefore, clinicians and ergonomists could consider this finding when developing successful rehabilitation programs and maintaining workplace safety.