Abstract des Autors

This study was designed to investigate the effect of an induced metabolic alkalosis on a 300 m sprinting time in six elite 400 m runners. The subjects competed as pairs, on two separate occasions, in a standard racing format, three hours after ingestion of either an alkaline (sodium citrate, 0.5 g/kg body weight) or a placebo solution (calcium carbonate, 0.5 g/kg body weight). The results showed that following alkaline ingestion mean sprinting time was not improved. Peak blood lactate during recovery was higher after sodium citrate administration than after placebo (19.88+/-2.09 vs 18.82+/-1.84 mmol/l, p<0.01). No difference was observed in peak blood ammonia between the alkaline and placebo treatments (187.0+/-37.0 vs 188.8+/-49.0 mirco-mol/l). The absence of effects on performance confirms that when exercise of short duration (30 to 40 s) is used, alkaline agents have minor or no effects on performance. The altered relationship observed between blood lactate and ammonia under placebo and buffering loading conditions suggests that the regulation of lactate and ammonia metabolism is unrelated. Verf.-Referat