[Eccentric muscle work--the unknown side of our movements].

Eccentric muscle work is an important part of our everyday activity, i.e. in breaking and preventing falls. Eccentric phases of movements improve the efficiency of cyclic repetitive activities. The molecular function in eccentric work is not understood, however its characteristics are a low metabolic demand and a high power output. Compared to concentric work there are only small differences in the hemodynamics of eccentric work. The muscle capacity for mechanical load is the limiting factor in eccentric work. Unaccustomed eccentric activity leads to damage of the cytoskeleton, which is the reason for delayed onset of muscle soreness. In sports and rehabilitation eccentric training can result in significant strength gain. Its use is today established to improve structures, which are exposed to eccentric loads in everyday activity. The high mechanical power may be promising in the musculoskeletal rehabilitation of patients with cardiopulmonary limitations.