Acute citrulline-malate supplementation is ineffective during aerobic cycling and subsequent anaerobic performance in recreationally active males

Citrulline-malate (CM) purportedly increases exercise performance through increased nitric oxide production. The effects of CM on muscular strength performance are well-documented; however, the benefits of CM on aerobic and anaerobic biking performance are not well researched. Therefore, the present investigation examined the acute CM supplementation effects on aerobic and anaerobic cycling performance in recreationally active males. Methods: 28 recreationally active males (20.9 +/- 2.8 years) completed randomized, double-blind, crossover trials consuming CM (12g dextrose + 8g CM) or a placebo (12g dextrose). Participants performed an aerobic cycling protocol (time-to-exhaustion [TTE]), followed by a subsequent 30-second Wingate cycling test, 60-minutes after supplement consumption. Results: Dependent t-tests showed no significant differences (p > 0.05) for TTE (PLA: 315.4 s +/- 137.7 s; CM: 314.1 s +/- 107.1 s) and Total Work Completed (TWC) (PLA: 74.7 +/- 34.1 kilojoules (kJ); CM: 74.1 +/- 26.4 kJ) during the aerobic cycling protocol. Dependent t-tests also showed no significant differences (p > 0.05) for mean watts (PLA: 586.1 +/- 87.7 Watts (W); CM: 588.0 +/- 93.0 W), peak watts (PLA: 773.0 +/- 136.7 W; CM: 786.7 +/- 133.0 W), and fatigue index (PLA: 12.9 +/- 6.4 FI; CM: 14.3 +/- 7.2 FI) during the Wingate protocol. Repeated-measures ANOVA results indicated a significant effect between each 5 s interval (p < 0.001), but no differences were observed between trials (p > 0.05). Conclusion: Acute CM supplementation in recreationally active males provides no ergogenic benefit in aerobic cycling performance followed by an anaerobic cycling test.