Effects of sensory deafferentation on glucose metabolism of muscles during locomotion

We measured the uptake of a radiolabeled analogue of glucose ([³H]FDG) into muscles during treadmill walking so as to determine whether sensory deafferentation of a limb affects the muscles' metabolic response to the exercise. The muscles on the deafferented side took up less tracer than those in the intact side with exercise, but not at rest. Extensor muscles were more affected than flexors by deafferentation. This agrees with the proposal that "reflex" inputs adjust the level of recruitment of motor units by central pattern generators.