Pre-exercise hyperventilation can significantly increase performance in the 50-meter front crawl

Abstract

Summary Objectives The aim of this study was to measure the effect of a 30-second pre-exercise maximal voluntary hyperventilation on the performance during a 50 m front crawl. Material and methods Nine well-trained swimmers (5 males [21.0 ± 8.5 years, 181.4 ± 3.5 cm, 71.2 ± 3.9 kg] and 4 females [21.0 ± 8.7 years, 166.2 ± 5.0 cm, 55.2 ± 2.2 kg]) performed a 50 m front crawl sprint either in normal conditions (NO) or after hyperventilation (HV) (6 maximal breathing cycles realized in 30 seconds followed by 30 seconds of rest). Results Average velocity for the 50 m front crawl was significantly higher after HV (1.81 ± 0.13 m.s−1 vs. 1.79 ± 0.14 m.s−1, P < 0.01). As a result, performance improves (27.79 ± 2.01 s vs. 28.08 ± 2.17 s, P < 0.01). The number of breathing cycles recorded during each race was significantly lower under HV compared to NO (1.88 ± 0.92 and 2.66 ± 1.41, P < 0.01). Moreover, the first air intake was significantly delayed under HV conditions (29.55 ± 8.67 vs. 23.55 ± 6.10 m, P < 0.01). The stroke rate was slightly increased under HV conditions while stroke length was kept nearly constant. Conclusion A pre-exercise maximal voluntary hyperventilation can significantly increase performance on the 50 m front crawl in well-trained swimmers.