Shorter gastrocnemius fascicle lengths in older adults associate with worse capacity to enhance push-off intensity in walking

Reduced push-off intensity during walking is thought to play an important role in age-related mobility impairment. We posit that an age-related shift toward shorter plantarflexor operating lengths during walking functionally limits force generation, and thereby the ability of those muscles to respond to increased propulsive demands during walking. To determine whether gastrocnemius muscle fascicle lengths during normal walking: (1) are shorter...