Muscle recruitment during plyometric exercises in overhead athletes with and without shoulder pain

Abstract Objectives To investigate if there is a difference in muscle activity patterns during high load plyometric shoulder exercises between overhead athletes with and without shoulder pain. Design Controlled laboratory EMG study. Setting University EMG Laboratory. Participants Sixty overhead athletes, 30 with shoulder pain and 30 healthy controls were included. Main outcome measures The EMG activity of Upper Trapezius (UT), Middle Trapezius (MT), Lower Trapezius (LT), Serratus Anterior (SA), Latissimus Dorsi (LD) and Pectoralis Major (PM) on the tested side and bilateral on Abdominal Obliques Externus (OE) muscles was registered with wireless surface EMG during 3 rotational plyometric shoulder exercises in 3 positions, prone, sidelying and standing. Results A significant higher muscle activity was found in the shoulder pain group for MT and SA together with an overall significant higher activity in the thoraco-humeral and abdominal muscles compared to healthy controls. Conclusions When rehabilitating the overhead athlete with shoulder pain, shoulder muscles together with both thoraco-humeral and abdominal muscles need to be engaged.