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

Amino Acids. 2007;32(3):381-6. doi: 10.1007/s00726-006-0474-z. Epub 2006 Nov 30.


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.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

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


  • beta-Alanine
  • Carnitine