Effect of glutamine supplementation combined with resistance training in young adults.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 11822473 · doi:10.1007/s00421-001-0523-y
What was done
Thirty-one healthy adults aged 18–24 years were randomized in a double-blind design to receive either oral glutamine (0.9 g/kg lean tissue mass/day; n = 17) or a maltodextrin placebo (0.9 g/kg lean tissue mass/day; n = 14) during 6 weeks of total-body resistance training (4–5 sets of 6–12 repetitions at 60–90% 1-repetition maximum). Before and after training, researchers measured 1 RM squat and bench press strength, peak knee extension torque (via isokinetic dynamometer), lean tissue mass (via DEXA), and muscle protein degradation (via urinary 3-methylhistidine).
What was found
Both groups showed significant increases with training (P < 0.05), but there were no significant differences between groups for any measure. Both groups increased 1 RM squat by approximately 30% and 1 RM bench press by approximately 14%. The glutamine group increased knee extension torque by 6%, lean tissue mass by 2%, and urinary 3-methylhistidine by 41%. The placebo group increased knee extension torque by 5%, lean tissue mass by 1.7%, and urinary 3-methylhistidine by 56%.
Why it matters
Oral glutamine supplementation does not provide additional benefits for muscle mass, strength, or protein degradation when combined with resistance training in healthy young adults.
Limits
The sample size was small (n = 31) and the intervention duration was short (6 weeks). The cohort was restricted to young healthy adults aged 18–24 years, precluding generalization to clinical catabolic states or older adults. Total daily dietary protein intake was not reported in the abstract.
Cited by
- supports Glutamine supplementation does not produce body composition improvements in young healthy individuals.