Cardiorespiratory metabolism during voluntary and electrical stimulation cycling in persons with advanced multiple sclerosis

Objective: To determine the relative benefit of electrical stimulation (ES) and voluntary cycling exercise for persons with moderate to severe multiple sclerosis (MS). Design: Case series. Setting: Laboratory/Disabled gymnasium. Participants: 5 females with moderate to severe multiple sclerosis who were experienced with neuromuscular electrical stimulation cycling exercise. Interventions: each participant completed 3 different trials on a stationary cycle ergometer. The first trial involved 2 periods (10-min) of voluntary exercise [VOL], the second 35-min of ES cycling exercise [ES], and the third was a combination of VOL and ES [ES+VOL]. Each trial was performed on a different day. Outcome Measures: Cardiorespiratory variables (VO₂, VCO₂, RQ, Vt, & Br/min), cycling power output, and heart rate [HR] were measured during each session. Participants were also asked to rate each exercise trial in terms of pain (0-10) and post-exercise tiredness (0-10). Results: On average ES+VOL elicited greater acute increases in aerobic metabolic but there was no statistically detectable difference between the 3 trials except for VCO₂. Conclusions: The application of ES may assist persons with severe MS to perform aerobic exercise. Further investigation is needed.