Maximum Absolute and Relative Joint Torques during Recovery from a Simulated Trip

Previous studies have shown that obesity negatively affects balance during quiet standing, yet little is known about its effect on the ability to recover after a postural perturbation. The purpose of this thesis was to investigate the effects of obesity on single-step balance recovery from an incipient forward fall. Eight obese (BMI = 33.2 ± 2.4) and eight non-obese (BMI = 24.8 ± 1.8) participants were released from a static forward lean and asked to recover their balance with a single step. Lean angle was progressively increased until they could no longer recover balance with a single step. Peak joint torques and relative effort during balance recovery were calculated and compared across the groups. Obese participants achieved a smaller maximum lean angle compared to non-obese participants. During balance recovery, obese participants exhibited higher ankle plantar flexor torques and relative effort. Trends also suggested higher relative hip extensor effort in the obese. Obese adults exhibited a poorer ability to recover from a forward fall with a single step. In addition, obese adults used a higher percentage of their total hip and ankle strength compared to non-obese adults during balance recovery. This suggests that the poorer ability of recovering from a forward fall in the obese may be related to increased exertion levels during balance recovery.