Mixed
Repeated sprint training in hypoxia (3000m simulated altitude) significantly increases the number of sprints to exhaustion compared to normoxic training, despite similar average power output improvements, by enhancing muscle blood perfusion and glycolytic capacity.
If you are a trained cyclist, adding 8 sessions of repeated sprint training in a hypoxic chamber (simulating 3000m) over 4 weeks can help you perform more sprints to exhaustion than if you did the same training in normal air. This happens because hypoxia triggers your body to increase blood flow to muscles and boost glycolytic enzymes, allowing you to delay fatigue during repeated high-intensity efforts. However, this does not necessarily increase your single-sprint peak power or your aerobic endurance (VO2max).
Our findings show larger improvement in repeated sprint performance in RSH than in RSN with significant molecular adaptations and larger blood perfusion variations in active muscles.
Why this rating
Randomized controlled trial with blinded assessment, moderate sample size (n=40 active), clear statistical significance (p<0.01) for the primary outcome (sprints to exhaustion).
Source
Significant Molecular and Systemic Adaptations after Repeated Sprint Training in Hypoxia
Raphaël Faiss et al. · PLoS ONE · 2013
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