[Muscle relaxation and muscle spindle adaptation].

In experiments on deefferented m. triceps surae of the cats, the unequal correlation between speed of muscle relaxation during interval from 2.5 to 40 sec after the beginning of static stretch and the rate of adaptation of three functionally different groups of muscle spindles, was revealed. The dependence of the adaptation of muscle spindle endings on relaxation of both extra-and intrafusal muscle fibers, is discussed.