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BRIEF RESEARCH REPORT article
Front. Sports Act. Living
Sec. Exercise Physiology
Volume 7 - 2025 | doi: 10.3389/fspor.2025.1524437
This article is part of the Research Topic Unraveling the Interconnected Dynamics of Exercise Metabolism, Environmental Stress, and Nutritional Factors View all 5 articles
Inter-individual variability in performance benefits from repeated sprint training in hypoxia and associated training parameters
Provisionally accepted- 1 Japan Women's College of Physical Education, Tokyo, Japan
- 2 The University of Tokyo, Bunkyo, Tōkyō, Japan
- 3 Surugadai University, Hanno, Saitama, Japan
- 4 University of Western Australia, Perth, Western Australia, Australia
This study examined whether inter-individual variability exists in repeated sprint training in hypoxia (RSH) and how peripheral oxygen saturation (SpO2) affects physiological demands and mechanical output, and subsequent training outcomes. Sixteen highly-trained sprint runners completed six sessions of RSH consisting of two sets of 5 × 10-s all-out sprints (fraction of inspired oxygen: 0.15), with pre-and post-tests involving 10 × 10-s all-out sprints in normoxia. Average SpO2, training impulse (TRIMP), and relative total work (relative TW; standardized by pre-test TW) during training sessions were calculated. After the intervention, MPO increased by +3.8% (P = 0.001) and sprint decrement score by +6.0% (P = 0.047). However, inter-individual variability in performance improvement observed and nearly 20% of participants did not obtain performance benefit. Average SpO2 during training sessions correlated significantly with relative TW (r = 0.435, P = 0.008), indicating that participants with higher SpO2 performed more work during training. Relative TW was strongly correlated with performance improvement (r = 0.833, P < 0.001), suggesting that those who produced more work during training experienced greater performance gains. TRIMP showed no significant correlation with SpO2 or performance improvement. In summary, greater peripheral deoxygenation leads to lower mechanical work and consequently smaller performance improvement following RSH. The variability in peripheral deoxygenation and relative TW among highly-trained sprint runners may contribute to the heterogeneous training effects observed.
Keywords: Inter-individual variability1, simulated altitude2, non-responder3, oxygen saturation4, repeated sprint training in hypoxia5. (Min
Received: 07 Nov 2024; Accepted: 31 Mar 2025.
Copyright: © 2025 TAKEI, Muraki, Girard and Hatta. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
NAOYA TAKEI, Japan Women's College of Physical Education, Tokyo, Japan
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