Effects of Intermittent Hypoxia Training on Exercise Performance, Hemodynamics, and Ventilation in Healthy Senior Men

Abstract

The efficacy and safety of intermittent hypoxia training (IHT) were investigated in healthy, 60- to 74-yr-old men. Fourteen men (Gr 1) who routinely exercised daily for 20 to 30 min were compared with 21 (Gr 2) who avoided exercise. Their submaximal work-load power values before the IHT training were 94 +/- 3.7 and 66 +/- 3.1, respectively. Before and after 10 days of IHT, the ventilatory response to sustained hypoxia (SH; 12% O(2) for 10 min), work capacity (bicycle ergometer), and forearm cutaneous perfusion (laser Doppler) were determined. During SH, no negative electrocardiogram (ECG) changes were observed in either group, and the ventilatory response to SH was unaltered by IHT. In Gr 1, IHT (normobaric rebreathing for 5 min, final Sa(O(2)) = 85% to 86%, followed by 5 min normoxia, 4/day) produced no changes in hemodynamic indixes and work capacity. In Gr 2, IHT decreased blood pressure (BP) by 7.9 +/- 3.1 mmHg (p < 0.05) and increased submaximal work by 11.3% (p < 0.05) and anaerobic threshold by 12.7% (p < 0.05). The increase in HR and BP caused by a 55 W-work load was reduced by 5% and 6.5%, respectively (p < 0.05). Cutaneous perfusion increased by 0.06 +/- 0.04 mL/min/100 g in Gr 1 and by 0.11 +/- 0.04 mL/min/100 g in Gr 2 (p < 0.05). Hyperemia recovery time increased significantly by 15.3 +/- 4.6 sec in Gr 1 and by 25.2 +/- 11.2 sec in Gr 2. Thus, healthy senior men well tolerate IHT as performed in this investigation. In untrained, healthy senior men, IHT had greater positive effects on hemodynamics, microvascular endothelial function, and work capacity.

Usefulness of combining intermittent hypoxia and physical exercise in the treatment of obesity

“…At the same time, it has been demonstrated that IHT may normalize blood pressure in hypertensive patients [123,124]. Moreover, it has been shown that systolic blood pressure is reduced after IHT, causing a hypotensive effect [43].…”

“…Increases blood serotonin levels [51] Ventilatory response during exercise increased [54] Normalises blood pressure [12,124] Improves insulin sensitivity [87] Appetite is suppressed [126,156] Improves respiratory function [68] Cardiovascular protection [155,163] Increases glucose transporter GLUT-4 [33,34] Increases body weight loss [84] 30 …”

“…Thus, protocols vary from those that examine the effect of as few as 3-12 relatively short (2-10 min) bouts of hypoxia interspersed with 2 to 20 min episodes of normoxia on a single day [15], to those that examine longer daily exposures (1-12 h) over periods ranging from 2 to 90 days [19,143], and those that consider short sinusoidal cycles of hypoxia/ normoxia (30-90 s) 7-8 h daily for 30-70 days [75]. Regardless of the schedule, the compelling outcome is that these repeated episodes of hypoxia elicit persistent changes in a variety of physiological responses [27,58,92,122,124]. …”

Fitness and therapeutic potential of intermittent hypoxia training: a matter of dose

“…This is the laboratory headed by Prof. O.Korkushko in the Institute of Gerontology, Kiev, Ukraine [28,29,77,79].…”

Tolerance to acute hypoxia maximally increases in case of joint effect of normobaric hypoxia and permissive hypercapnia in rats

“…Many researches in this field have dealt with intermittent hypoxic effects [9,18,21]. In addition, the comparative effectiveness of intermittent hypoxia with different numbers of exposures has also been described [13].…”