Team-Sport Athletes’ Improvement of Performance on the Yo-Yo Intermittent Recovery Test Level 2, but Not of Time-Trial Performance, With Intermittent Hypoxic Training

in International Journal of Sports Physiology and Performance
Restricted access

Purchase article

USD  $24.95

Student 1 year subscription

USD  $107.00

1 year subscription

USD  $142.00

Student 2 year subscription

USD  $203.00

2 year subscription

USD  $265.00


To determine the time course for physical-capacity adaptations to intermittent hypoxic training (IHT) in team-sport athletes and the time course for benefits remaining after IHT.


A pre–post parallel-groups design was employed, with 21 Australian footballers assigned to IHT (n = 10) or control (CON; n = 11) matched for training load. IHT performed eleven 40-min bike sessions at 2500-m altitude over 4 wk. Yo-Yo Intermittent Recovery Test level 2 (Yo-Yo IR2) was performed before; after 3, 6, and 11 IHT sessions; and 30 and 44 d after IHT. Repeated time trials (2- and 1-km TTs, with 5 min rest) were performed before, after, and 3 wk after IHT. Hemoglobin mass (Hbmass) was measured in IHT before and after 3, 6, 9, and 11 sessions.


Baseline Yo-Yo IR2 was similar between groups. After 6 sessions, the change in Yo-Yo IR2 in IHT was very likely higher than CON (27% greater change, effect size 0.77, 90% confidence limits 0.20;1.33) and likely higher 1 d after IHT (23%, 0.68, 0.05;1.30). The IHT group’s change remained likely higher than CON 30 d after IHT (24%, 0.72, 0.12;1.33) but was not meaningfully different 44 d after (12%, 0.36, –0.24;0.97). The change in 2-km TT performance between groups was not different throughout. For 1-km TT, CON improved more after IHT, but IHT maintained performance better after 3 wk. Hbmass was higher after IHT (2.7%, 0.40, –0.40;1.19).


Short-duration IHT increased Yo-Yo IR2 compared with training-load-matched controls in 2 wk. An additional 2 wk of IHT provided no further benefit. These changes remained until at least 30 d posttraining. IHT also protected improvement in 1-km TT.

Inness and Aughey are with the Inst of Sport, Exercise and Active Living, Victoria University, Melbourne, VIC, Australia. Billaut is with the Kinesiology Dept, Laval University, Québec, QC, Canada.

Address author correspondence to Robert Aughey at