Effect of forearm positions on scapular movements and trunk rotation angles.

[Purpose] The study investigated the impact of distinct forearm positions on scapular movement and trunk rotation angles. [Participants and Methods] We enrolled 23 healthy young males. Measurements of trunk rotation and relative scapular segment angles were acquired under three conditions employing three-dimensional motion analysis, each executed in a seated posture: (1) both forearms in a neutral position, (2) the forearm on the rotational side adopted supination while the opposite forearm utilized pronation, and (3) the forearm on the rotational side employed pronation while the opposite forearm assumed supination.