Repeated‐sprint training in hypoxia induced by voluntary hypoventilation improves running repeated‐sprint ability in rugby players

Purpose : The goal of this study was to determine the effects of repeated‐sprint training in hypoxia induced by voluntary hypoventilation at low lung volume (VHL) on running repeated‐sprint ability (RSA) in team‐sport players. Methods : Twenty‐one highly trained rugby players performed, over a 4‐week period, seven sessions of repeated 40‐m sprints either with VHL (RSH‐VHL, n = 11) or with normal breathing (RSN, n = 10). Before (Pre‐) and after training (Post‐), performance was assessed with an RSA test (40‐m all‐out sprints with a departure every 30 s) until task failure (85% of the reference velocity assessed in an isolated sprint). Results : The number of sprints completed during the RSA test was significantly increased after the training period in RSH‐VHL (9.1 ± 2.8 vs. 14.9 ± 5.3; +64%; p < .01) but not in RSN (9.8 ± 2.8 vs. 10.4 ± 4.7; +6%; p = .74). Maximal velocity was not different between Pre‐ and Post‐ in both groups whereas the mean velocity decreased in RSN and remained unchanged in RSH‐VHL. The mean SpO 2 recorded over an entire training session was lower in RSH‐VHL than in RSN (90.1 ± 1.4 vs. 95.5 ± 0.5%, p < .01). Conclusion : RSH‐VHL appears to be an effective strategy to produce a hypoxic stress and to improve running RSA in team‐sport players.