Effects of Two Short-Term, Intermittent Hypoxic Training Protocols on the Finger Temperature Response to Local Cold Stress

摘要

Keramidas, Michail E., Stylianos N. Kounalakis, Ola Eiken, and Igor B. Mekjavic. Effects of two short-term, intermittent hypoxic training protocols on the finger temperature response to local cold stress. High Alt Med Biol 16:251-260, 2015.-The study examined the effects of two short-term, intermittent hypoxic training protocols, namely exercising in hypoxia and living in normoxia (LL-TH; n=8), and exercising in normoxia preceded by a series of brief intermittent hypoxic exposures at rest (IHE+NOR; n=8), on the finger temperature response during a sea-level local cold test. In addition, a normoxic group was assigned as a control group (NOR; n=8). All groups trained on a cycle-ergometer 1 h/day, 5 days/week for 4 weeks at 50% of peak power output. Pre, post, and 11 days after the last training session, subjects immersed their right hand for 30 min in 8 degrees C water. In the NOR group, the average finger temperature was higher in the post (+2.1 degrees C) and 11-day after (+2.6 degrees C) tests than in the pre-test (p = 0.001). Conversely, the fingers were significantly colder immediately after both hypoxic protocols (LL-TH: -1.1 degrees C, IHE+NOR: -1.8 degrees C; p=0.01). The temperature responses returned to the pre-training level 11 days after the hypoxic interventions. Ergo, present findings suggest that short-term intermittent hypoxic training impairs sea-level local cold tolerance; yet, the hypoxic-induced adverse responses seem to be reversible within a period of 11 days.