Effect of L-citrulline intake on intermittent short-time high-intensity exercise performance in male collegiate track athletes

Abstract

Enhanced exercise performance and anti-fatigue effects following L-citrulline (Cit) intake have been reported in resistance training and endurance exercise, but not in intermittent short-time high-intensity exercise. Therefore, the effect of Cit intake on intermittent short-time high-intensity exercise performance in collegiate athletes was investigated. A double-blind, placebo-controlled crossover trial was performed using nine male collegiate track athletes (age 20.9 ± 1.6 years). Each participant ingested either Cit or a placebo (3 g [grams]/day) for 7 days and underwent Wingate test using a bicycle ergometer on days 0 and 7 performed three times using a pedaling load of 7.5% of the participant's weight for 30 s (seconds) at full power. As for the results, Cit intake significantly increased the change in mean power output, pedaling speed per 5 s, and power output per 5 s (Δday 7 -0) during pedaling as well as the change in oxygen consumption derived by analysis of expired gas. The amount of change in the rate of perceived exertion during exercise significantly decreased, and the amount of change in serum nitrite/nitrate (NOx) (Δday 7 -0) post-exercise was significantly increased compared to that of pre-exercise by Cit intake. These results suggested that Cit intake of 3 g/day for 7 days may have enhanced exercise performance and anti-fatigue effects on intermittent short-time highintensity exercise in male collegiate track athletes.

Effects of l-citrulline supplementation on nitric oxide and antioxidant markers after high-intensity interval exercise in young men: a randomised controlled trial

“…Estimation of an appropriate sample size was conducted using the G*Power analysis software (25) . Our rationale for sample size was based on a previous study evaluating changes in blood NOx responses to high-intensity exercise after acute L-Cit supplementation in nine young men (18,26) . This study revealed an effect size of 0•4 for the increase in NOx after high-intensity exercise.…”

“…Moreover, Stanelle et al (13) reported that L-Cit supplementation might lead to a slight improvement in the cycling performance of trained athletes. It was also shown that, due to exercise-induced muscle damage, L-Cit supplementation can decrease serum creatine kinase concentrations along with increasing perceived recovery (13,18) . According to prior research, L-Cit supplementation reduces concentrations of lactate and muscle pain 24 h after exercise (13,16) , which might be related to its antioxidant effects.…”