Abstract
This study examines the electromyographic (EMG) and joint movements seen during open (Cybex) and closed chain (StairMaster) exercises. The quadriceps, hamstrings, anterior tibialis, medial gastrocnemius, and gluteus muscle groups were monitored for EMG activity and joint movements (range-of-motion and angular velocity) while 10 subjects performed the aforementioned exercise patterns. Concentric muscular action was seen in both patterns of exercise, with greater co-contraction and synchronous actions being present with StairMaster exercise. The authors propose this exercise more closely simulates weightbearing/functional patterns, providing a strong recommendation for its use in rehabilitation of the lower extremity.