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

Issue Title: Special issue: Focus on Excitatory Amino Acids in Epilepsy This study examined the effects of 28 days of β-alanine supplementation on the physical working capacity at fatigue threshold (PWC^sub FT^), ventilatory threshold (VT), maximal oxygen consumption (O^sub 2-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 β-alanine (CarnoSyn(TM)) 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 PWC^sub FT^, VT, O^sub 2-MAX^, and TTE. There was a 13.9, 12.6 and 2.5% increase (p < 0.05) in VT, PWC^sub FT^, and TTE, respectively, for the β-alanine group, with no changes in the PL (p > 0.05). There were no changes for O^sub 2-MAX^ (p > 0.05) in either group. Results of this study indicate that β-alanine supplementation delays the onset of neuromuscular fatigue (PWC^sub FT^) and the ventilatory threshold (VT) at submaximal workloads, and increase in TTE during maximal cycle ergometry performance. However, β-alanine supplementation did not affect maximal aerobic power (O^sub 2-MAX^). In conclusion, β-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 ABSTRACT]