Factors limiting maximal oxygen uptake in exertional monoparesis

Abstract

Strength and maximal oxygen uptake (VO_2max) for each leg were compared in a trained multiple sclerosis (MS) patient with exertional left monoparesis. Left quadriceps strength and left leg VO_2max were 22% and 30% lower, respectively, compared to the right (control) leg. Because the same O₂ delivery system served each leg during exercise, VO_2max of the paretic leg was not limited by cardiorespiratory factors but rather by strength and/or muscle oxidative capacity. However, training with monoparesis likely enhanced O₂ extraction and aerobic work capacity of the right leg.

Keywords

exercise testing fatigue multiple sclerosis muscle strength

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