Microcirculatory and Metabolic Responses during Voluntary Cycle Ergometer Exercise with a Whole-Body Neuromuscular Electrical Stimulation Device

Abstract

Vigorous exercise increases blood viscosity and may pose a risk of cardiovascular events in patients with cardiovascular diseases. We recently reported that single-use of novel whole-body neuromuscular electrical stimulation (WB-NMES) can be safely applied in healthy subjects without adversely affecting blood fluidity. We performed a crossover study to explore the effectiveness and safety of a hybrid exercise with ergo-bicycle and WB-NMES; 15 healthy volunteers, aged 23–41 years, participated in this study. No arrhythmias were detected during the hybrid exercise and 20 min recovery, and although blood fluidity was transiently exacerbated immediately after both the exercise programs, in vivo parameters in the sublingual and nailfold microcirculation remained unchanged. There was a significant decrease in blood glucose and increase in lactic acid levels immediately after both exercise programs. Even with the same workload as the cycle ergometer exercise, the oxygen intake during the hybrid exercise remained higher than that during the cycle ergometer exercise alone (p < 0.05, r = 0.79, power = 0.81). Both the hybrid and voluntary cycle ergometer exercises transiently exacerbated blood fluidity ex vivo; however, microvascular flow was not adversely affected in vivo.