Prosthetic devices and methods of controlling the same are provided. A prosthetic ankle device includes a foot unit and lower limb member moveable relative to one another and defining an ankle angle therebetween. The prosthetic ankle device further includes a controller to operate the device using different ankle angles depending on, for example, a user's gait speed. Methods of controlling the prosthetic ankle device include operating the device at different ankle angles depending on gait speed. For example, the prosthetic ankle device can provide for relatively more dorsiflexion at relatively slower gait speeds and relatively more plantarflexion at relatively faster gait speeds.