Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6210285 | Journal of Electromyography and Kinesiology | 2015 | 6 Pages |
We tested the acute effect of exercises targeted simultaneously at cortical and brainstem circuits on neural transmission through corticobulbar connections. Corticobulbar pathways represent a potential target for rehabilitation after spinal cord injury (SCI), which tends to spare brainstem circuits to a greater degree than cortical circuits. To explore this concept, able-bodied volunteers (n = 20) underwent one session each of three exercises targeted at different nervous system components: treadmill walking (spinal locomotor circuits), isolated balance exercise (brainstem and other pathways), and multimodal balance plus skilled hand exercise (hand motor cortex and corticospinal tract). We found that short-interval soleus H-reflex facilitation increased after one session of balance and multimodal exercise by 13.2 ± 4.0% and 8.3 ± 4.7%, and slightly decreased by 1.9 ± 4.4% after treadmill exercise (p = 0.042 on ANOVA across exercise type). Increases in long-interval H-reflex facilitation were not significantly different between exercises. Both balance and multimodal exercise increased central motor conduction velocity by 4.3 ± 2.6% and 4.5 ± 2.8%, whereas velocity decreased by 4.3 ± 2.7% after treadmill exercise (p = 0.045 on ANOVA across exercise type). In conclusion, electrophysiological transmission between the motor cortex and spinal motor neurons in able-bodied subjects increased more following one session of balance exercise than treadmill exercise.