Abstract
The aim of this study was to determine the effects of subtetanic neuromuscular
electrical stimulation combined with voluntary exercise between repeated Wingate
tests on sprint exercise performance and blood lactate accumulation during
sprint interval training. Fifteen healthy young males volunteered. After 1-min
baseline, participants underwent the Wingate test twice. They performed a 4-min
intervention between tests: neuromuscular electrical stimulation with
free-weight cycling or voluntary cycling alone [43.6 (8.0) watts], which matched
oxygen consumption with neuromuscular electrical stimulation with free-weight
cycling. The blood lactate concentration was assessed at the end of the
baseline, at 3-min intervention, and on recovery at 1, 3, 5, and 10 min after
the second Wingate test. Peak and mean blood lactate concentration during
recovery were significantly greater with neuromuscular electrical stimulation
with free-weight cycling than voluntary cycling alone (P>0.036 and P=0.011,
respectively). Peak power, mean power, and rate of decline (fatigue index) were
not significantly different between conditions in both Wingate tests
(condition/interaction all P>0.300, partial η2<0.1). Subtetanic
neuromuscular electrical stimulation combined with voluntary exercise indicated
similar exercise performance and fatigue levels during Wingate tests, but
enhanced blood lactate accumulation compared to oxygen consumption-matched
voluntary cycling during sprint interval training.
Keywords
subtetanic neuromuscular electrical stimulation - lactate - sprint interval training