Upper limb strength in relation to upper limb posture

The aim of the study was to analyse values of the maximal forces of pushing, lifting, handgrip and torques of pronation and supination as well as to develop predictive equations expressing maximal force in relation to upper limb posture for four upper limb activities (pushing, lifting, pronation and supination). Twelve right-hand dominant men participated in the experimental study. All of them were healthy and had no history of hand dysfunction. They exerted maximal forces of the above-mentioned five different upper limb activities in 24 upper limb postures. Each upper limb posture was defined by seven angles. The analysis showed an influence of each of the seven angles on the exerted force. On the basis of the measurements obtained in the experimental study, predictive equations of the maximal force of pushing and lifting as well as torques of pronation and supination, in relation to the seven angles defining upper limb posture, were established. They make it possible to calculate maximal forces or torques in relation to upper limb posture and the type of upper limb activity. They can help designers in designing a workplace and therapists in measuring and comparing patients' capabilities.