Changes in resistance training performance, rating of perceived exertion, and blood biomarkers after six weeks of supplementation with L-citrulline vs. L-citrulline DL-malate in resistance-trained men: a double-blind placebo-controlled trial.
Davoud Bayat, Mohammad Azizi, Naser Behpour, Grant M Tinsley
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引用次数: 0
Abstract
Purpose: This study aimed to investigate and compare the effects of chronic supplementation with L-Citrulline (LC) vs. L-Citrulline DL-malate (CM) on resistance training (RT) performance.
Methods: Thirty-three resistance-trained men were randomly assigned to ingest LC (8 g), CM (12 g), or Placebo (PL) daily, along with participation in a 6-week RT protocol. Muscular strength (1-repetition maximum [1RM] for hack squat [HS] and bench press [BP]), muscular endurance (repetitions to failure [RTF] for HS, leg extension [LE], BP, and incline press [IP]), rating of perceived exertion (RPE), and blood biomarkers (lactate, urea, and nitric oxide metabolites [NOX]) were assessed before and after the intervention. This study was registered on irct.ir (IRCTID: IRCT20221128056642N1).
Results: Comparing mean ∆ scores revealed a significant difference between LC and PL (p < 0.001) and between CM and PL (p = 0.026) for total upper body (the sum of BP and IP) RTF, but only a trend for difference between LC and PL (p = 0.070) for total lower body (the sum of HS and LE) RTF. A significant time effect for NOX was detected only for LC (p = 0.014) and CM (p = 0.003). In addition, a significant difference between CM and PL (p = 0.009) and a marginally significant difference between LC and PL (p = 0.057) was detected regarding post-exercise NOX values at post-intervention. There were no other between-group differences for any outcome measure.
Conclusion: Chronic citrulline supplementation seems to enhance upper body muscular endurance and post-exercise NOX response to RT, but there is no apparent difference between LC and CM in these aspects.
期刊介绍:
Journal of the International Society of Sports Nutrition (JISSN) focuses on the acute and chronic effects of sports nutrition and supplementation strategies on body composition, physical performance and metabolism. JISSN is aimed at researchers and sport enthusiasts focused on delivering knowledge on exercise and nutrition on health, disease, rehabilitation, training, and performance. The journal provides a platform on which readers can determine nutritional strategies that may enhance exercise and/or training adaptations leading to improved health and performance.