Effects of beta-alanine supplementation on the onset of neuromuscular fatigue and ventilatory threshold in women.

Abstract

This study examined the effects of 28 days of beta-alanine supplementation on the physical working capacity at fatigue threshold (PWCFT), ventilatory threshold (VT), maximal oxygen consumption (VO2-MAX), and time-to-exhaustion (TTE) in women. Twenty-two women (age+/-SD 27.4+/-6.1 yrs) participated and were randomly assigned to either the beta-alanine (CarnoSyn) or Placebo (PL) group. Before (pre) and after (post) the supplementation period, participants performed a continuous, incremental cycle ergometry test to exhaustion to determine the PWCFT, VT, VO2-MAX, and TTE. There was a 13.9, 12.6 and 2.5% increase (p<0.05) in VT, PWCFT, and TTE, respectively, for the beta-alanine group, with no changes in the PL (p>0.05). There were no changes for VO2-MAX (p>0.05) in either group. Results of this study indicate that beta-alanine supplementation delays the onset of neuromuscular fatigue (PWCFT) and the ventilatory threshold (VT) at submaximal workloads, and increase in TTE during maximal cycle ergometry performance. However, beta-alanine supplementation did not affect maximal aerobic power (VO2-MAX). In conclusion, beta-alanine supplementation appears to improve submaximal cycle ergometry performance and TTE in young women, perhaps as a result of an increased buffering capacity due to elevated muscle carnosine concentrations.

• Authors: J R Stout, J T Cramer, R F Zoeller, D Torok, P Costa, J R Hoffman, R C Harris, J O'Kroy
• Journal: Amino acids (Amino Acids) Vol. 32 Issue 3 Pg. 381-6 ( 2007) ISSN: 0939-4451 [Print] Austria
• PMID: 17136505 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial)

Chemical References

• beta-Alanine
• Carnitine

Topics

• Adult
• Carnitine (metabolism)
• Dietary Supplements
• Female
• Humans
• Mental Fatigue (metabolism, prevention & control)
• Muscle Fatigue (drug effects)
• Muscle, Skeletal (metabolism)
• Oxygen Consumption (drug effects)
• Physical Endurance (drug effects)
• beta-Alanine (administration & dosage)