Ankle moment effects on hip joint angular accelerations during walking in healthy young and older adults

When walking at similar speeds, greater positive hip extensor and/or flexor work is thought to compensate for lower positive ankle work during push-off in older versus young adults. Ankle moments contribute to positive ankle work in walking and are reduced in old age. We used induced acceleration analysis to determine the causal links between reduced ankle moments and increased hip joint kinetics during aging. Results suggest that older adults do not increase ipsilateral hip flexor - but may increase contralateral hip extensor - kinetic output to compensate for lower ankle moments in level/uphill walking.