Effects of a L-citrulline supplementation on nitric oxide and blood lactate in young women after a maximum exercise session

The consumption of sports supplements and their effects on the performance of athletes needs to be evaluated. The purpose of this study was to determine the effects of L-citrulline supplementation on nitric oxide (NO) and blood lactate in young women after a maximal exercise session.Methods & Materials: The research method was quasi-experimental with double blind design. After filling out the health questionnaire, 24 voluntary inactive young women with body mass index less than 25 kg/m2 were randomly divided into two groups (n=12) and placebo (n=12). Subjects visited the laboratory twice; in the first session, the first blood samples were taken immediately after the exercise protocol. After 5 minutes of warm-up, the subjects were performed the Bruce treadmill test protocol to time to exhaustion. Then the supplement group consumed 6 grams daily L-citrulline powder and placebo (starch powder) for one week. The second session was performed one week later in the same conditions as the first session. Immediately after the test, time to exhaustion was recorded, blood samples collected and lactate and NO plasma levels measured. Analysis of variance with repeated measures with significant level p < 0.05 was used for analyzing data. The results showed that there was no significant difference between time to exhaustion, plasma levels of lactate and NO of two groups (placebo and supplement) in two sessions.Discussion & It seems that acute supplementation of L-citrulline has no effect on nitric NO and blood lactate in young women after a maximal exercise session.