Effect of sodium bicarbonate ingestion upon repeated sprints.

The purpose of the study was to assess the effect of sodium bicarbonate ingestion upon repeated bouts of intensive short duration exercise. Twenty-three subjects participated in the investigation (8 females and 15 males, age 21.4 +/- 2.3, mean +/- sd). Subjects completed six trials; three following the ingestion of sodium bicarbonate (300 mg/kg body weight) and three following the ingestion of a placebo (8 g sodium chloride). Each trial consisted of ten ten-second sprints on a cycle ergometer with 50 seconds recovery between each sprint. 'Peak power' and 'average power output' during each ten second sprint was measured from the flywheel of the ergometer using a light-sensitive monitor (Cranlea) linked to a BBC microcomputer. The power outputs recorded during each ten-second sprint of the bicarbonate trials were then compared with those recorded during the corresponding sprint of the placebo trials. The bicarbonate trials produced higher mean 'average power' outputs in all ten of the ten-second sprints, with the difference in 'average power' output being statistically significant in eight of these (p less than 0.05). The results also revealed that the difference in the 'average power' outputs attained during the bicarbonate and placebo trials increased as the number of sprint repetitions increased (p less than 0.01). 'Peak power' output was also greater in the bicarbonate trials with it being significantly higher (p less than 0.001) during the final ten-second sprint. It was concluded that during exercise consisting of repeated, short-duration sprints, power output was enhanced following the ingestion of sodium bicarbonate, (300 mg/kg body weight).