Gait speed measurements will be collected by the blinded evaluator at study entry (if possible), at 1, 2, 4, 6, and 8 weeks after entry if still an inpatient, within one day of inpatient discharge, and, if possible, 3 months and 6 months after study entry. The Functional Ambulation Classification Index will be completed by the blinded evaluator after each gait speed assessment. Thus, a FAC score will be recorded at the same time points as each gait speed evaluation.