Association of Foot Structure with the Strength of Muscles that Move the Ankle and Physical Performance.

The human foot plays an important role in supporting body weight, maintaining postural balance, and absorbing ground reaction forces. Although many studies have indicated that a causal relationship exists between foot structure and alterations in lower extremity kinematics, there is little evidence regarding the possible association of foot structure with strength of muscles that move the ankle and physical performance. A total of 67 adult men with a mean age of 51.19 ± 8.82 years participated in this study. Foot structural parameters were assessed using a 3-dimensional foot scanner. Strength of muscles that move the ankle was measured with a dynamometer. Physical performance items, including agility, force, and proprioception, were also measured. We found that all the measured parameters of the length, width, girth, and height of the foot were positively correlated with the strength of plantarflexion, dorsiflexion, eversion, and inversion (r ranged from 0.26 to 0.57; p < .05). Moreover, all or part of the parameters of the length, width, and girth of the foot but not the height and angles of the foot were correlated significantly with vertical jump, stepping forward and backward, and stepping side to side (r ranged from 0.25 to 0.44; p < .05). These findings indicate a weak-to-moderate association between foot structure and the strength of muscles that move the ankle, as well as physical performance. We therefore suggest that a larger foot may have greater muscle strength of the ankle joint and better physical performance.