| Popis: |
Physiological mechanisms of neuronal adaptation of the human corticospinal pathways in response to long-term intense motor activity have been studied insufficiently. In this work, we investigated adaptational changes in corticospinal mechanisms of muscular contraction control in athletes. We measured parameters of motor evoked potentials of lower limb skeletal muscles under voluntary static loads of various intensity and duration, using the transcranial magnetic stimulation method. Elite athletes, as compared to the reference group, in the course of increased intensity and duration of isometric muscular contractions demonstrated more expressed increase in the maximum amplitude of the motor evoked potentials of lower limb skeletal muscles, smaller decrease in the time of central motor conduction of nervous pulses and the peripheral period in electromyograms, and less expressed increase in the cortical and segmental silent periods. Mechanisms of adaptation of corticospinal regulation of human muscular contraction to specific conditions of extreme motor activities are discussed. |
