Analysis of effect of hold depth and hold angle on climbers' pullup biomechanics

This study aims to investigate the effects of hold sloper angle and hold depth on the climbers' pull-up biomechanics. 13 recreational climbers performed 2-repetition pull-up movements on 3 different sloper angle (0°, 20°, 30°) and 3 different hold depth (20 mm, 40 mm, 60 mm) combinations, during which motion capture, force and electromyography data were recorded. These data were then statistically analyzed using two-way repeated measured ANOVA method in SPM. Certain parameters derived from the biomechanical data were discretely analyzed using two-way repeated measured ANOVA. The results revealed that with holds having greater sloper angles or with narrower holds, the pull-up was executed in a more controlled manner in the antero-posterior direction. Using the holds with greater sloper angles the maximal force and movement speed during the ascend phase were less; and the highest vertical position at the top was lower. With holds having greater depths, the maximal force and movement speed during the ascend phase and the highest vertical position at the top was higher. It was observed that the hold variation had no effect on the asymmetry between the left and right extremities in terms of force production. Holds with greater sloper angles yielded more activation in the finger flexor muscles and in lower trapezius muscle. As the hold depth decreased the activation of flexor digitorum profundus increased. During the ascend phase of the pull-up the muscles reached their maximal activation in the lower trapezius, biceps brachii and lattisimus dorsi order.