Introduction: Carnosine, a dipeptide of the amino acids beta-alanine and histidine, has several physiological roles that might explain enhanced exercise performance. Studies have demonstrated a beneficial effect of beta alanine supplementation on high intensity exercise performance (Hobson et al, 2012). However, no study to date has examined the effects on longer duration cycling performance. Furthermore, although carnosine has been suggested to have a number of effects within the brain (Sale et al, 2013), the effects of betaalanine supplementation on cognitive function in athletes has not previously been examined. Method: Nineteen UK category 1 male cyclists completed four 20 km cycling time trials (on their own racing bikes attached to a Cyclus 2 ergometer), two before and two after 4 weeks of supplementation with either 6.4 g/d beta-alanine (n=10; BA) or a matched placebo (n=9; P). Performance time for the 20 km time trial was recorded, as were the split times for every 1 km. Capillary blood samples were taken at baseline, immediately following the time trial and again after completing the cognitive function tests for determination of blood lactate. Heart rate was recorded after every 1 km and RPE after every 5 km. A battery of cognitive function tests (Stroop test, Sternberg paradigm and RVIP task) was completed before, and immediately following, the time trial. Results: There was no significant effect of beta-alanine supplementation on 20 km time trial performance (BA pre 1943±129 s; BA post 1950±147 s; P pre 1989±106 s; P post 1986±115 s; supplement by time interaction, p=0.624) or on the performance of each 1 km split (all p>0.05). The effect of beta-alanine on 20 km time trial performance was deemed unclear as determined by magnitude based inferences. Similarly, there were no effects of beta-alanine supplementation on blood lactate concentrations, heart rate or RPE (all p>0.05). Furthermore, beta-alanine supplementation did not affect cognitive function at rest, or mediate the effects of exercise on any component of cognitive function examined (all p>0.05). Discussion: Supplementation with 6.4 g/d of betaalanine for 4 weeks did not affect 20 km cycling time trial performance in well trained male cyclists. Furthermore, beta-alanine supplementation did not affect any aspect of cognitive function at rest, or mediate the effects of exercise on cognitive function.
© Copyright 2014 19th Annual Congress of the European College of Sport Science (ECSS), Amsterdam, 2. - 5. July 2014. Veröffentlicht von VU University Amsterdam. Alle Rechte vorbehalten.