Frequently (25-75% of the time) performed tasks - Standing, sitting with and without back support, walking, reaching (overhead, forward, lateral, and low), crouching, balancing, lifting 5-25 pounds, carrying 5-10 pounds, and pushing up to 75 pounds. Physical Requirements: Ability to walk without assistive device and to maintain balance despite sudden load in order to support patient from falling during ambulation and/or gait training.