Methods to match high-intensity interval exercise intensity in hypoxia and normoxia - A pilot study.


Li Y., Li J., Atakan M. M. , Wang Z., Hu Y., Nazif M., ...More

Journal of exercise science and fitness, vol.20, no.1, pp.70-76, 2022 (Peer-Reviewed Journal) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 20 Issue: 1
  • Publication Date: 2022
  • Doi Number: 10.1016/j.jesf.2021.12.003
  • Journal Name: Journal of exercise science and fitness
  • Journal Indexes: Science Citation Index Expanded, Scopus, CAB Abstracts, CINAHL, Food Science & Technology Abstracts, SportDiscus, Directory of Open Access Journals
  • Page Numbers: pp.70-76
  • Keywords: High-intensity interval exercise, Hypoxia, Exercise prescription, Peak power output, Lactate threshold, GAS-EXCHANGE, INCREMENTAL EXERCISE, CYCLING PERFORMANCE, AEROBIC PERFORMANCE, NORMOBARIC HYPOXIA, LACTATE THRESHOLD, LEVEL, POWER, PEAK

Abstract

© 2021 The Society of Chinese Scholars on Exercise Physiology and FitnessObjectives: The aim of this study was to compare high-intensity interval exercise (HIIE) sessions prescribed on the basis of a maximal value (peak power output, PPO) and a submaximal value (lactate threshold, LT) derived from graded exercise tests (GXTs) in normoxia and hypoxia. Methods: A total of ten males (aged 18–37) volunteered to participate in this study. The experimental protocol consisted of a familiarization procedure, two GXTs under normoxia (FiO2 = 0.209) and two GXTs under normobaric hypoxia (FiO2 = 0.140), and three HIIE sessions performed in a random order. The HIIE sessions included one at hypoxia (HY) and two at normoxia (one matched for the absolute intensity in hypoxia, designated as NA, and one matched for the relative intensity in hypoxia, designated as NR). Results: The data demonstrated that there was significant lower peak oxygen uptake (V̇O2peak), peak heart rate (HRpeak), PPO, and LT derived from GXTs in hypoxia, with higher respiratory exchange ratio (RER), when compared to those from GXTs performed in normoxia (p < 0.001). Among the three HIIE sessions, the NA session resulted in lower percentage of HRpeak (85.0 ± 7.5% vs 94.4 ± 5.0%; p = 0.002) and V̇O2peak (74.1 ± 9.1% vs 88.7 ± 7.7%; p = 0.005), when compared to the NR session. HIIE sessions in HY and NR resulted in similar percentage of HRpeak and V̇O2peak, as well as similar rating of perceived exertion and RER. The blood lactate level increased immediately after all the three HIIE sessions (p < 0.001), while higher blood lactate concentrations were observed immediately after the HY (p = 0.0003) and NR (p = 0.014) sessions when compared with NA. Conclusion: Combining of PPO and LT derived from GXTs can be used to prescribe exercise intensity of HIIE in hypoxia.