Maximizing anaerobic performance with repeated-sprint training in hypoxia: In search of an optimal altitude based on pulse oxygen saturation monitoring

Abstract

Purpose: Repeated-sprint training in hypoxia (RSH) leads to great improvements in anaerobic performance. However, there is no consensus about the optimal level of hypoxia that should be used during training to maximize subsequent performances. This study aimed to establish whether such an optimal altitude can be determined and whether pulse oxygen saturation during RSH is correlated with training-induced improvement in performance.Methods: Peak and mean power outputs of healthy young males [age (mean ± SD) 21.7 ± 1.4 years] were measured during a Wingate (30 s) and a repeated-sprint ability (RSA; 10 x 6-s sprint with 24-s recovery) test before and after RSH. Participants performed six cycling sessions comprising three sets of 8 x 6-s sprint with 24-s recovery in normobaric hypoxia at a simulated altitude of either 1,500 m, 2,100 m, or 3,200 m (n = 7 per group). Heart rate variability was assessed at rest and during recovery from Wingate test before and after RSH.Results: The subjective rating of perceived exertion and the relative exercise intensity during training sessions did not differ between the three groups, contrary to pulse oxygen saturation (p < 0.001 between each group). Mean and peak power outputs were significantly increased in all groups after training, except for the mean power in the RSA test for the 3200 m group. Change in mean power on RSA test (+8.1 ± 6.6%) was the only performance parameter significantly correlated with pulse oxygen saturation during hypoxic training (p < 0.05, r = 0.44). The increase in LnRMSSD during recovery from the Wingate test was enhanced after training in the 1,500 m (+22%) but not in the two other groups (≈– 6%). Moreover, the increase in resting heart rate with standing after training was negatively correlated with SpO2 (p < 0.01, r =–0.63) suggesting that hypoxemia level during training differentially altered autonomic nervous system activity.Conclusion: These data indicate that RSH performed as early as 1,500 m of altitude is effective in improving anaerobic performance in moderately trained subjects without strong association with pulse oxygen saturation monitoring during training.

Exercise responses to repeated cycle sprints with continuous and intermittent hypoxic exposure

“…As expected, we observed higher hypoxia‐induced physiological stress as reflected by lower SpO 2 readings during sprints, recoveries, or both (I‐HYP SPRINT , I‐HYP RECOVERY , and C‐HYP conditions, respectively) in low oxygen conditions. These SpO 2 values were comparable to that reported for similar hypoxia severity (i.e., ∼80%–85% at FiO 2 = ∼13%) (Brocherie, Millet, & Girard, 2017 ; Goods et al., 2014 ; Gutknecht et al., 2022 ). In the RSE literature, the extent to which heart rate responses and/or blood lactate concentrations are exaggerated compared to sea‐level controls is more circumstantial (Girard, Brocherie, & Millet, 2017 ).…”

Effects of various living-low and training-high modes with distinct training prescriptions on sea-level performance: A network meta-analysis

“…The significant decrease in SaO 2 implies greater demand for and stimulation of anaerobic metabolism. Nevertheless, caution is needed as the more severe the hypoxia, the greater the interference with autonomic nervous system activity [ 82 , 83 ], leading to the accumulation of fatigue and stress. Therefore, the real-time monitoring of physiological characteristics and training intensity is vital in ensuring the successful execution of hypoxia training.…”

Three sessions of repeated sprint training in normobaric hypoxia improves sprinting performance

“…According to the results provided by Hamlin et al [ 27 ], the SpO 2 level could increase at the second training day of hypoxic exposure relative to the first training day under hypoxic exposure. It is well known that as hypoxia degree increases, SpO 2 level and physical working capacity decrease inversely [ 24 , 25 , 39 ]. Furthermore, the exposed hypoxia level may cause different responses according to individual variability [ 23 , 40 ].…”