Abstract des Autors

Background: To study the plasma ammonia response after sprint crawl swimming. Methods: Nine sprinters (S) and ten non-sprinters (NS) completed a 15-, a 25- and a 50-m crawl at maximal intensity with a 10-min and a 15-min resting period inbetween. Capillary blood samples were collected before and at regular intervals after each effort for plasma ammonia determination. Results: Ammonia kinetics differed among distances, but not between groups, with peak values (observed 2-8 min postexercise) being higher after 50 m as compared to shorter distances. Significant differences between S and NS were found in peak ammonia after 50 m (124.5+/-58.2 vs 98.7+/-6.3 micro-mol/L) and in the change of ammonia relative to swim time (delta NH3/delta t) after 25 m (2.66+/-1.87 vs 1.49+/-0.84 micro-mol/L/s) and 50 m (1.87+/-1.33 vs 1.01+/-0.49 micro-mol/L/s). Delta NH3/delta t was highest after 15 m (3.33+/-2.53 in S, 3.92+/-1.67 micro-mol/L/s in NS). Conclusions: These differences in the plasma ammonia response to sprint swimming according to duration and athlete seem to be connected to distinctions in muscle fiber profile and energy providing processes. Verf.-Referat