The walking program will continue until T4 and T4a. Each participant will be scheduled for this testing within 10 calendar days of the 24-week anniversary of the commencement of outpatient therapy. At this testing time (T4 & T4a) all outcome measures will be repeated. The final testing time (T5 and T5 a) will be completed within 10 calendar days of 288-day anniversary of commencement of outpatient physical therapy. All outcome measures will be repeated at this testing time. This will be the termination point of the study.