Effect of L-Aspartate on Power in Intercollegiate Athletes

Abstract

L-Aspartate supplementation lowers blood ammonia and may improve performance when ammonia is sufficiently elevated (i.e. >[100uM/L]) in response to power demands. In sports such as water polo, athletes use a combination of the anaerobic and aerobic systems to increase power during competition. However, the optimum relative peak performance power (W·kg−1·min−1) in these events is unclear, as well is the potential for L-Aspartate supplementation to improve power. PURPOSE To investigate the ability of L-Aspartate to increase power. METHODS Ten highly-trained intercollegiate water polo players (WP) and nine competitive intercollegiate athletes (IND) in upper body sports (i.e. tennis, surfing) exercised to exhaustion on an arm ergometer on two occasions (48 h washout). Each test followed double-blind ingestion (24 h pre and 1 h pre) of 12.5g ± 2 of L-Asp (A) or placebo (P), respectively. All-out power began at the 200W 4-minute mark of an incremental (25W·30 second−1) 100-rpm warm-up for WP, and RPE 17 (6–20 scale) for IND, at which point the subjects turned the crank ‘as fast as possible for as long as possible’. RESULTS Power (W·kg−1·min−1) was higher (p<0.05) for A (2.9 ± 0.9) vs. P (2.6 ± 0.5). In WP, power was 21% greater (p<0.05) with A (3.4 ± 0.9) vs. P (2.8 ± 0.5). In IND, there was no difference in A (2.3 ± 0.3) vs. P (2.2 ± 0.4).TABLE 1: Effect of L-Aspartate on relative power (W.kg-1·min-1CONCLUSION L-Aspartate supplementation may be an effective ergogenic aid for competitive athletes using prolonged high-intensity power surges. Caution should be used for application to other sports using comparatively shorter surges, such as tennis. Future work may consider protocols with exhaustion occurring between 30 to 60 seconds in the performance phase.