Ankle muscles co-activation during walking: A gender comparison in adults and children

The present study aimed to evaluate possible gender-related differences in adults and children co-activation and antagonistic behavior of ankle muscles (Tibialis Anterior and Gastrocnemius) during walking. The statistical gait analysis technique, applied to a total of 40 subjects (20 children and 20 young adults), allowed the statistical description of gait, considering spatial-temporal and electromyography parameters over a large number (hundreds) of consecutive strides per subject. Co-activations were computed as the overlapping periods of muscles bursts, while antagonism occurred when no simultaneous muscular activity was detected. Outcomes showed no significant differences in temporal characteristics of co-activations in children and adults. Evaluating antagonistic and co-contraction activity in terms of number of strides where each pattern happened, i.e. their occurrence frequency, no significant differences were observed between males and females in children, while in adults group co-contraction pattern resulted significantly more recurrent in females with respect to males. Furthermore, the direct comparison between adults and children showed significant differences in the recurrence of both co-activation and antagonist pattern only for males. Results suggested a possible age-related change in males muscular recruitment during walking, which could lead to the gender differences in co-contraction activity observed in adults but not in children.