Ankle bracing in running: the effect of a Push type medium ankle brace upon movements of the foot and ankle during the stance phase.

Functional ankle braces are designed to limit medio-lateral movements of the ankle without affecting ankle dorsiflexion or plantar flexion. As running forms a basic activity in sports, the current study investigated the influence of wearing a Push type medium ankle brace upon movements of the foot and ankle during the stance phase in running. The movements of the lower extremity of seven trained male long-distance runners were filmed frontally (250 s-1) and sagittally (50 s-1) while running at 4.5 +/- 0.1 m.s-1 over a Kistler force platform. The tested brace significantly reduced the range (total subtalar eversion 13.3 deg vs 18.1 deg, p < 0.05) and rate of subtalar eversion (maximal velocity -309 deg.s-1 vs -533 deg.s-1). Plantar and dorsiflexion were not affected. The vertical impact force peak was not altered. It was argued that, although this might not be the prime design feature of the tested ankle brace, this orthotic offers a strategy to influence the range and the rate of subtalar eversion. It may have the potential to prevent runners from overuse injuries associated with overpronation, but interaction between the passive support by the brace and the muscular stabilization of the ankle joint needs further investigation.