Effects of simulated weight loss on lower extremity emg and joint kinematics during treadmill walking in obese subjects

Due to changes in segmental volume and mass during weight loss, the role of body weight per se on gait characteristics in obesity is poorly understood. We measured lower extremity EMG activity and sagittal plane joint angles in obese women (N=3) walking on a positive-pressure treadmill (0 and 25% body weight support [BWS]) at a self-selected pace (0 and 10% incline). Compared to basal, inclined walking increased iEMG of all muscles (10-46%). Conversely, BWS decreased iEMG of knee extensors and plantarflexors (8-18%), but increased iEMG of knee flexors (9%). BWS curtailed the effects of inclined walking on iEMG of the knee extensors and plantarflexors, but additively increased iEMG of knee flexors. Despite independently increasing peak knee flexion and plantarflexion, combined incline and BWS did not affect peak sagittal plane joint angles.