Effects of Resistance Training on Obesity-induced Biomechanics and Physical Limitations

Obesity predisposes over one-third of American adults to lower extremity osteoarthritis, joint pain, and functional limitations, in large part, due to altered biomechanics during activities of daily living (ADLs). Historically, excess body mass has been blamed for obesity-induced biomechanical adaptations, and weight loss interventions have been recommended to correct these adaptations. However, recent data indicates that obesity impairs skeletal muscle contractile function (strength, power, and endurance) and alters muscle recruitment patterns during activities of daily living. To date, the role of skeletal muscle contractile dysfunction and altered muscle recruitment in biomechanics of obese subjects has not been explored. This study aims to determine the relationship between skeletal muscle function and biomechanics and physical performance in obese subjects. Furthermore, this study will determine how a short-term exercise training intervention designed to improve muscle function and recruitment affects biomechanics of obese subjects. We hypothesize that muscle function, but not body mass per se, is associated with altered 3D kinematics of obese subjects during ADLs. We further hypothesize that an exercise intervention consisting of resistance and functional movement training will reduce the effects of obesity on biomechanics during ADLs.