The rotator cuff muscles are activated at low levels during shoulder adduction: an experimental study Darren Reed, Mark Halaki, Karen Ginn Journal of Physiotherapy Volume 56, Issue 4, Pages 259-264 (January 2010) DOI: 10.1016/S1836-9553(10)70009-6 Copyright © 2010 Australian Physiotherapy Association Terms and Conditions
Figure 1 Experimental setup for isometric adduction at 90° abduction in the scapular plane. Journal of Physiotherapy 2010 56, 259-264DOI: (10.1016/S1836-9553(10)70009-6) Copyright © 2010 Australian Physiotherapy Association Terms and Conditions
Figure 2 Mean (SD) muscle activation during maximum (100% load) isometric shoulder adduction at 30°, 60°, and 90° abduction for 11 shoulder muscles. * = activity levels of teres major, latissimus dorsi, and rhomboid major were significantly higher than all other muscles at all loads (all pairwise comparisons p < 0.05), including 100% load as shown here. EMG = electromyographic activation, MVC = maximum voluntary contraction. Journal of Physiotherapy 2010 56, 259-264DOI: (10.1016/S1836-9553(10)70009-6) Copyright © 2010 Australian Physiotherapy Association Terms and Conditions
Figure 3 Mean muscle activation during isometric shoulder adduction at 25%, 50%, 75%, and 100% of maximum load and at 30°, 60° and 90° abduction for 11 shoulder muscles. EMG = electromyographic activation, MVC = maximum voluntary contraction, shading = muscles activated ≤ 10%. Journal of Physiotherapy 2010 56, 259-264DOI: (10.1016/S1836-9553(10)70009-6) Copyright © 2010 Australian Physiotherapy Association Terms and Conditions