Acute effects of pre-exercise voluntary hyperventilation on the time course of power output and cardiorespiratory responses during a 30-s wingate test

Voluntary hyperventilation (HV) induces hypocapnic respiratory alkalosis and has been proposed as a non-invasive ergogenic strategy for high-intensity exercise; however, its time-dependent effects within a single all-out bout remain unclear. This study examined the effects of pre-exercise HV on mechanical power output, pulmonary gas exchange, and cardiovascular responses during a 30-s Wingate Anaerobic Test (WAnT), analyzed in consecutive 10-s segments. In a randomized crossover design, 18 male competitive athletes completed a control session and an HV session (30 breaths·min − 1 for 2 min) before a 30-s WAnT. Power output, breath-by-breath gas exchange, and heart rate (HR) were averaged over 0–10, 10–20, and 20–30 s and analyzed using two-way (condition × time) repeated-measures ANOVA. The HV session elicited higher relative peak power (main effect of condition, p = .024; 0–10 s: 13.51 ± 2.09 vs. 12.67 ± 1.83 W·kg − 1 , p = .018) and relative mean power (0–10 s: 11.26 ± 1.52 vs. 10.71 ± 1.28 W·kg − 1 ; p = .028) than the control session. The fatigue index (FI) was greater with HV (58.80 ± 13.71% vs. 49.02 ± 8.87%; p = .002). Minute ventilation (V̇ E ) was lower with HV at 10–20 s ( p = .029) and 20–30 s ( p = .004). Ventilatory equivalents were higher with HV at 0–10 s (V̇ E /V̇O 2 : p = .043; V̇ E /V̇CO 2 : p < .001), whereas V̇ E /V̇O 2 was lower at 20–30 s ( p = .025). End-tidal CO 2 pressure (P ET CO 2 ) was lower at 0–10 s ( p < .001), and HR was lower with HV at 20–30 s ( p = .017). Two minutes of pre-exercise HV produced a transient increase in power output limited to the first 10 s of the WAnT, accompanied by a greater fatigue index and phase-specific changes in ventilatory and HR responses. Thus, HV appears to alter the time course of the response to all-out exercise rather than improve overall 30-s performance. ClinicalTrials.gov, NCT07797205, registered 23 August 2026. Retrospectively registered.