Treadmill Training at Constant or Different Speeds for People With Traumatic Brain Injury

Objectives: To test the effectiveness of using time varying walking velocity in Body-Weight Supported Treadmill Training (BWSTT) as compared to using constant velocity in subjects with Traumatic Brain Injury (TBI). We hypothesize that using time varying velocity will result in a greater improvement in ambulatory function. Study Population: 30 adult subjects with a clinical diagnosis of non-penetrating TBI and with functional deficits in gait will be enrolled. Subjects will be recruited from NIH, affiliated hospitals/clinics, and in the community. Design: This pilot study will use an instrumented treadmill (Bertec Co., Columbus, Ohio) and a force controlled harness system called ZeroG (Aretech LLC, Ashburn, Virginia). Subjects will be randomly assigned to one of two groups (12 subjects per group): the first group will receive BWSTT at a constant velocity (also known as standard treadmill training); and the second group will receive BWSTT at randomized time varying velocity. BWSTT at time varying velocity consists of two components: 1) subjects passively adjusting their walking speed to the continuously changing speed of the treadmill; and 2) subjects actively changing their walking speed by following the instructed walking speed displayed on a monitor screen while the treadmill is automatically adjusted to the subjects speed. Each group will receive 8 gait training sessions (30 minutes per session, twice per week) for four weeks. Gait performance will be tested before (pre-test) and after (post-test) the 8 session gait training program. Outcome Measures: The primary outcome measures are parameters representing gait performance: maximum walking speed, self-selected walking speed, cadence, stride length, percentage of swing, stance and double stance periods, gait symmetry, Time Up and Go (TUG), and Dynamic Gait Index (DGI) scores. The secondary outcome measure is physical and cognitive effort exerted during the training session as evaluated by grip-strength test and LNS (Letter-Number Sequencing) test.