title: The effect of l-citrulline and watermelon juice supplementation on anaerobic and aerobic exercise performance.
abstract: Citrulline has been proposed as an ergogenic aid, leading to an interest in watermelon given its high citrulline concentration. The aim of this study was to determine the effects of a single, pre-exercise dose of l-citrulline, watermelon juice, or a placebo on the total maximum number of repetitions completed over 5 sets, time to exhaustion, maximal oxygen consumption (VO2max), anaerobic threshold, and flow-mediated vasodilation. A randomised double-blind within-participants study design was used to examine these effects among 22 participants (n = 11 males). Supplementation included either a 7.5% sucrose drink containing 6 g of l-citrulline, 710 mL of watermelon juice (~1.0 g citrulline), or a 7.5% sucrose placebo drink. Supplementation was administered 1 or 2 h before exercise testing to investigate a timing effect. There was no significant effect between the three supplements for the total number of repetitions, time to exhaustion, VO2max, anaerobic threshold, or flow-mediated vasodilation. There was also no interaction observed relative to gender or supplement timing (P > 0.05). A single dose of l-citrulline or watermelon juice as a pre-exercise supplement appears to be ineffective in improving exercise performance; however, greater doses of l-citrulline have been shown to be safe and are currently left unexamined.
authors.affiliation: a Exercise Science and Sport , The University of Scranton , Scranton , PA , USA.
authors.forename: Paul T
authors.initials: PT
authors.lastname: Cutrufello
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Gadomski
authors.forename: Gerald S
authors.initials: GS
authors.lastname: Zavorsky
mesh_terms: D015308:Anaerobic Threshold / Q000502:physiology; D002956:Citrulline / Q000008:administration & dosage*; D029773:Citrullus; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D014664:Vasodilation; D014891:Weight Lifting / Q000502:physiology; D055815:Young Adult
chemical_list: D002956:Citrulline
keywords: amino acid; ergogenic aid; supplement