title: Acute Citrulline-Malate Supplementation and High-Intensity Cycling Performance.
abstract: Cunniffe, B, Papageorgiou, M, O'Brien, B, Davies, NA, Grimble, GK, and Cardinale, M. Acute citrulline-malate supplementation and high-intensity cycling performance. J Strength Cond Res 30(9): 2638-2647, 2016-Dietary L-citrulline-malate (CM) consumption has been suggested to improve skeletal muscle metabolism and contractile efficiency, which would be expected to predispose exercising individuals to greater fatigue resistance. The purpose of this study was to examine the effects of CM supplementation on acid-base balance and high-intensity exercise performance. In a double-blind, placebo-controlled, crossover study, 10 well-trained males consumed either 12 g of CM (in 400 ml) or lemon sugar-free cordial (placebo [PL]) 60 minutes before completion of 2 exercise trials. Each trial consisted of subjects performing 10 (×15 seconds) maximal cycle sprints (with 30-second rest intervals) followed by 5 minutes recovery before completing a cycle time-to-exhaustion test (TTE) at 100% of individual peak power (PP). Significant increases in plasma concentrations of citrulline (8.8-fold), ornithine (3.9-fold), and glutamine (1.3-fold) were observed 60 minutes after supplementation in the CM trial only (p ≤ 0.05) and none of the subjects experienced gastrointestinal side-effects during testing. Significantly higher exercise heart rates were observed in CM condition (vs. PL) although no between trial differences in performance related variables (TTE: [120 ± 61 seconds CM vs. 113 ± 50 seconds PL]), PP or mean power, ([power fatigue index: 36 ± 16% CM vs. 28 ± 18% PL]), subjective rating of perceived exertion or measures of acid-base balance (pH, lactate, bicarbonate, base-excess) were observed (p > 0.05). This study demonstrated that acute supplementation of 12 g CM does not provide acute ergogenic benefits using the protocol implemented in this study in well-trained males.
authors.affiliation: 1Institute of Sport, Exercise and Health, University College London, London, United Kingdom; 2English Institute of Sport, Bisham Abbey, Marlow, United Kingdom; 3Institute of Liver and Digestive Health, Faculty of Medical Sciences, University College London, London, United Kingdom; 4Center for Gastroenterology and Nutrition, Faculty of Medical Sciences, University College London, London, United Kingdom; and 5Aspire Academy, Doha, Qatar.
authors.forename: Brian
authors.initials: B
authors.lastname: Cunniffe
authors.forename: Maria
authors.initials: M
authors.lastname: Papageorgiou
authors.forename: Barbara
authors.initials: B
authors.lastname: OʼBrien
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Davies
authors.forename: George K
authors.initials: GK
authors.lastname: Grimble
authors.forename: Marco
authors.initials: M
authors.lastname: Cardinale
mesh_terms: D000136:Acid-Base Equilibrium / Q000187:drug effects*; D000328:Adult; D002956:Citrulline / Q000031:analogs & derivatives* / Q000097:blood / Q000494:pharmacology; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005973:Glutamine / Q000097:blood; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008293:Malates / Q000494:pharmacology*; D008297:Male; D009952:Ornithine / Q000097:blood; D010807:Physical Endurance / Q000187:drug effects* / Q000502:physiology; D055815:Young Adult
chemical_list: D008293:Malates; D005973:Glutamine; D002956:Citrulline; D019344:Lactic Acid; D009952:Ornithine; C071162:citrulline malate