Therefore the data indicates that the latissimus dorsi displays peak moment arm lengths between 10 — 71 degrees of shoulder flexion depending on the region measured. (strengthandconditioningresearch.com)
Keuchle et al. (1997) reports the change in moment arm length with the change in shoulder flexion range of motion. (strengthandconditioningresearch.com)
Ackland et al. (2008) showed that the anterior deltoid provided the largest peak moment arm length during shoulder flexion in the scapular plane displaying a peak muscle moment arm of 39.3 mm at 120 degrees (arms over head). (strengthandconditioningresearch.com)