Training conditions that best reproduce the joint powers of unsupported walking.
OBJECTIVE
To identify the clinically relevant combinations of body weight support and speed that best reproduce the joint powers of unsupported walking.


METHODS
Timing and magnitude of lower extremity joint powers were calculated for 8 neurologically intact volunteers (4M/4F) walking with 0%, 30% and 50% body weight support at three speeds (slow, comfortable, and fast). Lower extremity joint power absorption was analyzed during weight acceptance and forward propulsion. In addition, power generation was analyzed during forward propulsion. Timings and magnitudes of joint powers per condition were evaluated to identify the training combinations of body weight support and speed that best preserved the powers of unsupported walking at slow, comfortable and fast speeds.


RESULTS
For all speeds examined, increasing body weight support to 30% without changing speed provided the best match. In general, changes in speed disrupted the joint power magnitudes and timings more than application of body weight support. Increasing body weight support when faster training speeds were used proved a viable method for reproducing the joint powers of slow, unsupported walking.


CONCLUSIONS
These data provide a reference for understanding the effect of potential training conditions on power absorption and generation within the lower extremity joints during walking. It is possible to reproduce the joint powers of unsupported walking with certain combinations of body weight support and speed. We recommend applying adequate levels of BWS when training speeds are faster than the overground speed goal, as occurs during treadmill-based locomotor rehabilitation of individuals with incomplete spinal cord injury.
Department of Physical Medicine and Rehabilitation, The Ohio State University, Columbus, OH, United States. Electronic address: lise.worthen-chaudhari@osumc.edu.
Lise
L
Worthen-Chaudhari
Department of Aerospace and Mechanical Engineering, The University of Notre Dame, South Bend, IN, United States.
James P
JP
Schmiedeler
School of Health and Rehabilitation Sciences, The Ohio State University, Columbus, OH, United States.
D Michele
DM
Basso
D000328:Adult; D001835:Body Weight; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007596:Joints / Q000503:physiopathology*; D008297:Male; D009989:Orthotic Devices; D013119:Spinal Cord Injuries / Q000503:physiopathology / Q000534:rehabilitation*; D016138:Walking / Q000502:physiology*; D016474:Weight-Bearing; D055815:Young Adult
Biomechanics; Gait; Locomotor training; Neurorehabilitation; Spinal cord injury; Weight acceptance