Neuromuscular electrical stimulation: no enhancement of recovery from maximal exercise

Purpose: To investigate the use of neuromuscular electrical stimulation (NMES) during acute recovery between 2 bouts of maximal aerobic exercise. Methods: On 3 separate days, 19 trained male cyclists (28 ± 7 y, 76.4 ± 10.4 kg, power output at maximal aerobic power [pVo2max] 417 ± 44 W) performed a 3-min maximal cycling bout at 105% PVo2max before a 30-min randomly assigned recovery intervention of passive (PAS: resting), active (ACT: 30% PVo2max), or NMES (5 Hz, 4 pulses at 500 μs). Immediately afterward, a cycle bout at 95% PVo2max to exhaustion (TLIM) was performed. Heart rate (HR) and blood lactate (BLa) were recorded at designated time points. Data were analyzed using repeated-measures ANOVA with a Tukey honestly significantly different post hoc test. Statistical significance threshold was P < .05. Results: The TLIM was significantly shorter for NMES than for ACT (199.6 ± 69.4 s vs 250.7 ± 105.5 s: P = .016) but not PAS recovery (199.6 ± 69.4 s vs 216.4 ± 77.5 s: P = .157). The TLIM was not significantly different between ACT and PAS (250.7 ± 105.5 s vs 216.4 ± 77.5 s: P = .088). The decline in BLa was significantly greater during ACT than NMES and PAS recovery (P < .001), with no difference between NMES and PAS. In addition, HR was significantly higher during ACT than NMES and PAS recovery (P < .001), with no difference between NMES and PAS. Conclusions: NMES was less effective than ACT and comparable to PAS recovery when used between 2 bouts of maximal aerobic exercise in trained male cyclists.