Electromyographic assessment of the lower leg muscles during concentric and eccentric phases of standing heel raise

Only a small number of muscle activation patterns from the lower limb have been reported and simultaneous muscle activation from several lower limb muscles have not been investigated. The purpose of this study was to examine any gender differences in surface electromyography (EMG) activity from six recorded lower limb muscles of the dominant limb at baseline (i.e. with the foot placed flat on the floor and in the neutral position), and during concentric and eccentric phases when performing a heel raise task. Ten females and ten males performed a standing heel raise task comprising of three continuous phases: baseline, unloading (concentric muscle action) and loading (eccentric muscle action) phases. Muscle activation from six muscles (gastrocnemius medialis, gastrocnemius lateralis, soleus, tibialis anterior, peroneus longus and peroneus brevis) were measured using the Myon 320 EMG System. Root Mean Squared values of each muscle were calculated for each phase. Descriptive and inferential statistics were incorporated into the study. Statistically significant P values were set at 0.05. The results showed no significant differences between baseline, concentric and eccentric phases with respect to each of the muscles investigated. Except for the gastrocnemius medialis at baseline and concentric phases, no significant differences were observed between genders or contractions. These data suggest that gender does not seem to significantly influence the eccentric phase during the standing heel raise task.