Functional state of the spinal centers of the bilateral lower limbs in athletes

The aim of the study was to estimate the reflex excitability of motor responses of the bilateral lower limbs in athletes under single exposure to transcutaneous electrical stimulation of the spinal cord (tSCES) in the coccygeal plexus at the Co₁-Co₂ level and the post-activation effect of short-term noninvasive rhythmic electrical stimulation (rES) of the coccygeal plexus on the functional state of the spinal centers of the bilateral antagonist muscles of the thigh and tibial leg.

In 30 athletes aged 18-27 years, specializing in short-distance running, the amplitude of the MERs of the muscles of the thigh (RF – musculus rectus femoris, BF – m. biceps femoris) and tibial (TA – m. tibialis anterior, GM – m. gastrocnemius medialis) leg was evaluated at a maximum single stimulus force (90 mA) along the midline of the coccygeal plexus Co₁-Co₂ and the effect of 10and 60-second rES on the excitability of MNs of the muscles of the lower limbs caused by a single stimulus force at the level of the T11-T12 vertebrae.

A single electrical stimulation of the coccygeal plexus causes a greater reflex excitability of the motor neuronal pools of the extensor of the tibia of the bilateral extremities. The reflex excitability of MNs caused by stimulation in the coccygeal plexus is more pronounced in the spinal flexor centers of the thigh and tibial extensor of the left limb than in the symmetrical muscles of the right limb. rES of the coccygeal plexus leads to multidirectional changes in the excitability of MNs of the muscles of the thigh and tibial leg of the bilateral lower limbs: in some athletes, the excitability increased, in others it decreased. The post-activation effect rES of the coccygeal plexus, regardless of its duration of effect, has mainly, on average, a group of athletes, facilitating effect on the motor neuronal pools of the spinal centers of the antagonist muscles of the bilateral lower limbs.

The methods of registering the MERs of the bilateral lower extremities in response to moderate single percutaneous electrical stimulation of the coccygeal plexus in the area of Co₁-Co₂ and rES coccygeal plexus can be used in clinical and sports medicine, and as one of the methods of intraoperative neurophysiological monitoring in patients.

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