The Effects Of Citrulline Malate Supplementation In Strength And Muscle Mass

Abstract

L-citrulline (CIT) is a non-essential amino acid, found abundantly in watermelon, which has the ability to indirectly increase nitric oxide production by increasing arginine levels. A combination and the acute use of CIT with malate (intermediate of the Krebs cycle) has shown interesting results in the sports science literature, but the chronic effect of citrulline malate (CM) in the scientific literature is still unclear. PURPOSE: Investigate the chronic effects of citrulline malate supplementation in increasing strength and muscle mass in trained healthy adults. METHODS: A randomized, double-blind, crossover, placebo clinical study. Twenty four (25.96 ± 4.7 years) healthy adult men were randomly divided into 2 groups; citrulline malate group (CM= 12; 82.4±10.7kgs) or placebo group (PL = 12; 82.11±10,9kgs). The CM group received a sachet containing 6g of citrulline malate + 15g of maltodextrin and the PL group 6g of non-essential amino acids (NAAE) + 15g of maltodextrin. Supplementation was performed for 28 days (4 weeks) and included a wash-out week. After this week, there was an exchange of supplements in both groups. Before and after each supplementation, body composition (body weight, fat mass and muscle mass) by plethysmography (BodPod), and repetition maximum test (1RM) in the bench press were performed. Statistical analysis was performed using the covariance analysis model for crossover experiments, considering a significance level p<0.05. RESULTS: CM supplementation promoted an increase in total lean mass (67.28 ± 8.11kgs vs 67.77 ± 7.97kgs, p<0.005) in relation to placebo (67.83 ± 7.84kgs vs 67.43 ± 8.57kgs) (CM vs PL p<0.001), a decrease in total weight (CM 82.39 ± 10.72kgs vs 81.63 ± 9.98kgs and PL 82.11 ± 10.9kgs vs 82.08 ± 9.78kgs, CM vs PL p<0.05) and an increase in the final bench press (CM 37.95 ± 7.6kgs vs 41.55 ± 8.31kgs, p<0.05) in relation to placebo supplementation (38.26 ± 8.69kgs vs 40.08 ± 8.19kgs, p<0.05) (CM vs PL, p<0.01), regardless of the sequence in which the supplement was ingested. CONCLUSION: Supplementation of CM for 4 weeks proved to be effective in improve body composition (decrease in total weight and increase lean mass) and increased strength, without showing adverse effects, indicating a viable strategy for practitioners of resistance exercise.