Supplementation with beta-hydroxy-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) reduces signs and symptoms of exercise-induced muscle damage in man

Int J Sport Nutr Exerc Metab. 2005 Aug;15(4):413-24. doi: 10.1123/ijsnem.15.4.413.

Abstract

This study examined the effects of beta-hydroxyl-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) supplementation on signs and symptoms of exercise-induced muscle damage following a single bout of eccentrically biased resistance exercise. Six non-resistance trained male subjects performed an exercise protocol designed to induce muscle damage on two separate occasions, performed on the dominant or non-dominant arm in a counter-balanced crossover design. Subjects were assigned to an HMB/KIC (3 g HMB and 0.3 g alpha-ketoisocaproic acid, daily) or placebo treatment for 14 d prior to exercise in the counter-balanced crossover design. One repetition maximum (1RM), plasma creatine kinase activity (CK), delayed onset muscle soreness (DOMS), limb girth, and range of motion (ROM) were determined pre-exercise, at 1h, 24 h, 48 h, and 72 h post-exercise. DOMS and the percentage changes in 1RM, limb girth, and ROM all changed over the 72 h period (P < 0.05). HMB//IC supplementation attenuated the CK response, the percentage decrement in 1RM, and the percentage increase in limb girth (P < 0.05). In addition, DOMS was reduced at 24 h post-exercise (P < 0.05) in the HMB/KIC treatment. In conclusion, 14 d of HMB and KIC supplementation reduced signs and symptoms of exercise-induced muscle damage in non-resistance trained males following a single bout of eccentrically biased resistance exercise.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Creatine Kinase / blood
  • Creatine Kinase / metabolism
  • Cross-Over Studies
  • Dietary Supplements
  • Double-Blind Method
  • Humans
  • Isometric Contraction
  • Keto Acids / administration & dosage
  • Keto Acids / pharmacology*
  • Male
  • Muscle, Skeletal / drug effects*
  • Muscle, Skeletal / injuries*
  • Range of Motion, Articular / drug effects
  • Range of Motion, Articular / physiology
  • Torque
  • Valerates / administration & dosage
  • Valerates / pharmacology*
  • Weight Lifting / injuries
  • Weight Lifting / physiology*

Substances

  • Keto Acids
  • Valerates
  • beta-hydroxyisovaleric acid
  • alpha-ketoisocaproic acid
  • Creatine Kinase