Repeated-Sprint Training in Hypoxia Induced by Voluntary Hypoventilation at Low Lung Volume: A Meta-analysis.

BACKGROUND

Repeated-sprint training in hypoxia (RSH) induced through voluntary hypoventilation at low lung volume (RSH-VHL) may represent a low-cost alternative to systemic hypoxia. This meta-analysis aimed to systematically assess the effects of RSH-VHL training interventions on sea-level physical performance compared to similar repeated-sprint training with normal breathing (RSN).

METHODS

The PubMed/MEDLINE, SportDiscus, ProQuest, and Web of Science online databases were examined from inception to February 2025 for original studies investigating the changes in physical performance following RSH-VHL and RSN. Only trained participants were included. Standardized mean difference (SMD) was determined for repeated-sprint ability related variables [i.e., best and mean performance (RSA and RSA), sprint decrement score (S)] and maximal blood lactate concentration ([La]). PEDro scale and Begg & Mazumbar test were used to assessed risk of bias.

RESULTS

From the 776 studies identified through systematic search, 10 studies including a total of 199 individuals (157 males and 42 females) were eligible for meta-analysis. While no effect was observed for RSA (SMD = 0.038; 95%CI - 0.252-0.328; P = 0.798) and RSA (SMD = 0.276; 95%CI - 0.018-0.570; P = 0.066), moderate significant effects were observed for S (SMD = 0.603; 95%CI 0.180-1.025; P = 0.005) and [La] (SMD = 0.611; 95%CI 0.223-0.999; P = 0.002) favoring RSH-VHL vs. RSN.

CONCLUSION

Repeated-sprint training in hypoxia induced by voluntary hypoventilation at low lung volume provides putative gains in fatigue resistance during repeated sprints. Higher maximal blood lactate concentration suggests greater glycolytic contribution during RSH-VHL compared to RSN. Mechanisms underlying these effects are currently unclear and have yet to be identified.