[Biochemical and functional changes in skeletal muscles with electrostimulation]

Electrostimulation of rabbit muscles for 18 days is accompanied by a disturbance in certain biochemical indices and functional state of the muscles. This is confirmed by a decrease in ATP content, intensity of Ca2+ uptake by the sarcoplasmatic reticulum fragments, by a drop in exitability (by the indices of rheobase and chronaxia) as well as by a change in the structure of muscular fibres components, motor axons, motor nerve endings and sciatic nerve stems. Less developed changes are observed when electrostimulation is performed for 5 days and twice for 5 days, including the period of rest. In this case the changes in Atp content and visual deviations in the muscles structure are absent and only the ability of the sarcoplasmatic reticulum fragments to Ca2+ uptake decreases insignificantly and the muscles excitability increases. Administration of ATP and simultaneous electrostimulation for 5 days normalize the disturbed Ca2+ uptake and preserve the higher excitability, that makes it possible to consider this regime of training to be the most acceptable.