The effects of 8 weeks of heavy resistance training and branched-chain amino acid supplementation on body composition and muscle performance

Nutr Health. 2012 Oct;21(4):263-73. doi: 10.1177/0260106013510999.

Abstract

Purpose: This study determined the effects of 8 weeks of heavy resistance training combined with branched-chain amino acid (BCAA) supplementation on body composition and muscle performance.

Methods: Resistance training was performed by 19 non-resistance-trained males (three sets of 8-10 repetitions) four times/week, for 8 weeks, while also ingesting 9 g/day of BCAA or 9 g/day of placebo (PLAC) on the exercise days only (one-half of total dose 30 min before and after exercise). Data were analyzed with separate 2 × 2 analysis of variance (ANOVA) (p < 0.05).

Results: For total body mass, neither group significantly increased with training (p = 0.593) and also, there were no significant changes in total body water (p = 0.517). In addition, no training- or supplement-induced (p = 0.783) changes occurred with fat mass or fat-free mass (p = 0.907). Upper-body (p = 0.047) and lower-body strength (p = 0.044) and upper- (p = 0.001) and lower-body muscle endurance (p = 0.013) increased with training; however, these increases were not different between the groups (p > 0.05).

Conclusion: When combined with heavy resistance training for 8 weeks, supplementation with 9 g/day of BCAA 30 min before and after exercise had no preferential effects on body composition and muscle performance.

Keywords: Amino acid; body composition; exercise; muscle mass; muscle performance; muscle strength; supplementation; weight training.

MeSH terms

  • Adolescent
  • Adult
  • Amino Acids, Branched-Chain / administration & dosage*
  • Amino Acids, Branched-Chain / adverse effects
  • Analysis of Variance
  • Body Composition* / drug effects
  • Body Composition* / physiology
  • Body Mass Index
  • Diet Records
  • Dietary Supplements* / adverse effects
  • Double-Blind Method
  • Humans
  • Male
  • Muscle Strength / physiology*
  • Muscle, Skeletal / physiology
  • Patient Compliance / statistics & numerical data
  • Physical Endurance / drug effects
  • Physical Endurance / physiology
  • Placebos
  • Resistance Training / methods*
  • Surveys and Questionnaires
  • Time Factors
  • Young Adult

Substances

  • Amino Acids, Branched-Chain
  • Placebos