Influence of experience on kinematics of upper limbs during sewing gesture.

To teach a skilled motor task, it is crucial to understand the characteristics of expertise. The aim of the present study was to compare the kinematics of the hand sewing task between novices (n = 10), intermediates (n = 10) and experts (n = 10). Compared to novices and intermediates, the proximal joint of expert participants was less involved in the task than their distal joints. The shoulder of experts stayed closer to the trunk, while the ranges of motion of the wrist and fingers were higher. This ability enabled them to avoid lifting the arm, which was resting on the table. We observed a low cycle-to-cycle variability of the movement pattern for experts, while it was more variable in novices. Moreover, experts shared similar joints synergies attesting of an "experts" common gesture. This knowledge gained about the hand sewing kinematics can be used to refine the training process of dressmakers.