Comparative Kinematics of Full-Weight-Bearing and Suspended Running

Abstract

1805 Treadmill-unweighting devices may be used to retrain gait in patients with poor muscle activation, low weight bearing capacity, and poor balance. It is assumed that full-weight-bearing (FWB) and suspended running share similar kinematic patterns. PURPOSE: To use kinematic variables to determine the degree of similarity between FWB and suspended running. METHODS: Ten male runners (21.4 ± 1.5 yrs, 68.4 ± 3.3 kg) with similar running fitness and experience ran on a treadmill at 3.8 m•s−1. A suspension harness and pneumatic lift device were used to suspend a subject. Three conditions were tested: FWB, 20 percent suspended weight (20S), and 40 percent suspended weight (40S). 3-D video data were collected to analyze the following kinematic variables: cycle length (YL); contact time (CT); cycle time (YT); hip flexion/extension (HF); leg crossover at footstrike (LC); torso rotation (TR); and vertical displacement of the center of mass (CM). RESULTS: Descriptive statistics are included in the table below (mean ± SD). Separate One-Way ANOVAs indicated significant differences between FWB and suspended conditions for YL, YT, HF and CM (p<0.05). CONCLUSION: Expected differences were observed between the FWB and suspended conditions due to the suspension design. Similarity was found in kinematic running variables LC and TR, but not in HF. These data suggest a high degree of similarity between FWB and suspended running. Support through grant from the Undergraduate Research Opportunities Program, University of Minnesota.Table