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On two separate days eight male subjects performed a 10‐ or 20‐s cycle ergometer sprint (randomized order) followed, after 2 min of recovery, by a 30‐s sprint. Muscle biopsies were obtained from the vastus lateralis at rest, immediately after the first sprint and after the 2 min of recovery on both occasions.The anaerobic ATP turnover during the initial 10 s of sprint 1 was 129 ± 12 mmol kg dry weight⁻¹ and decreased to 63 ± 10 mmol kg dry weight⁻¹ between the 10th and 20th s of sprint 1. This was a result of a 300% decrease in the rate of phosphocreatine breakdown and a 35% decrease in the glycolytic rate. Despite this 51% reduction in anaerobic ATP turnover, the mean power between 10 and 20 s of sprint 1 was reduced by only 28%. During the same period, oxygen uptake increased from 1.30 ± 0.15 to 2.40 ± 0.23 L min⁻¹, which partially compensated for the decreased anaerobic …