Effects of Interval Training Under Hypoxia on the Autonomic Nervous System and Arterial and Hemorheological Function in Healthy Women

Hun-Young Park; Won-Sang Jung; Sung-Woo Kim; Kiwon Lim

doi:10.2147/IJWH.S344233

Effects of Interval Training Under Hypoxia on the Autonomic Nervous System and Arterial and Hemorheological Function in Healthy Women

Int J Womens Health. 2022 Feb 2:14:79-90. doi: 10.2147/IJWH.S344233. eCollection 2022.

Authors

Hun-Young Park^{1

2}, Won-Sang Jung², Sung-Woo Kim², Kiwon Lim^{1

2

3}

Affiliations

¹ Department of Sports Medicine and Science, Graduated School, Konkuk University, Seoul, Republic of Korea.
² Physical Activity and Performance Institute (PAPI), Konkuk University, Seoul, Republic of Korea.
³ Department of Physical Education, Konkuk University, Seoul, Republic of Korea.

Abstract

Purpose: The present study verified the effects of interval training under hypoxia, a novel exercise modality for health promotion, on the autonomic nervous system (ANS) and arterial and hemorheological function in healthy women.

Methods: Twenty healthy Korean women (age: 19-29 [24.85 ± 3.84] years) were equally assigned to interval normoxic training (INT, n = 10; residing and training under normoxia) and interval hypoxic training (IHT, n = 10; residing under normoxia and training under 526 mmHg hypobaric hypoxia) groups. All participants performed 90-min of training sessions composed of 15-min of warm-up, 60-min of interval training, and 15-min of cool-down. The interval training sessions composed of 10 repetitions of interval exercise using a treadmill (5 min of exercise corresponding to 90-95% maximal heart rate [HR] and 1 min of rest). The training was performed 3 days per week for 6 weeks. All participants underwent body composition, HR variability, brachial-ankle pulse wave velocity, flow-mediated dilation (FMD), red blood cell (RBC) deformability and aggregation, and maximal oxygen uptake (VO₂max) measurements before and after training.

Results: There were no significant differences in body composition between the groups. The IHT group showed a significant improvement in the ANS function (root mean square of successive differences, high frequency, and low frequency/high frequency ratio), arterial stiffness, arterial endothelial function (FMD), hemorheological function (RBC deformability and aggregation), and aerobic performance (VO₂max) compared with the INT (all p < 0.05).

Conclusion: In comparison with the interval training under normoxia, the interval training under hypoxia is a novel and effective exercise modality for promoting aerobic performance with the ANS and arterial and hemorheological function in healthy women.

Keywords: arterial endothelial function; arterial stiffness; erythrocyte deformability and aggregation; heart rate variability; hypoxia; interval training; maximal oxygen uptake.

Grants and funding

This work was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF-2019S1A5B8099542). This study was also supported by the KU Research Professor Program of Konkuk University.