Vascular adaptations to hypobaric hypoxic training in postmenopausal women

Abstract

The objective of this study was to examine the effects of exercise training in hypoxia on arterial stiffness and flow-mediated vasodilation (FMD) in postmenopausal women. Sixteen postmenopausal women (56±1 years) were assigned to a normoxic exercise group (Normoxic group, n=8) or a hypoxic exercise group (Hypoxic group, n=8). The Hypoxic group performed exercise under hypobaric hypoxic conditions corresponding to 2000 m above sea level, and was exposed to these conditions for 2 h per session. Aquatic exercise was performed at an intensity of around 50% peak oxygen uptake for 30min, 4days per week, for 8 weeks. Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV), and FMD was evaluated by peak diameter of the popliteal artery during reactive hyperemia. After the 8 weeks of training, the Normoxic group showed no significant changes. In contrast, baPWV (P < 0.05) was significantly reduced and peak diameter (P<0.05) and %FMD (P<0.01) were significantly increased in the Hypoxic group after training. These results suggest that exercise training under mild intermittent hypoxic conditions could more effectively reduce arterial stiffness in postmenopausal women, compared with exercise training performed at the same relative intensity under normoxic conditions. Our data also indicate that hypoxic exercise training may induce vascular functional adaptation, for example an increase in FMD response. These findings therefore could have important implications for the development of a new effective exercise prescription program.

Influences of Short-Term Normobaric Hypoxic Training on Metabolic Syndrome-Related Markers in Overweight and Normal-Weight Men

“…5 In addition, Nishiwaki et al reported that hypoxic training increased fl ow-mediated vasodilation (FMD) (an indicator of increased blood fl ow) and reduced PWV, similar to the results of this study. 21 Katayama et al reported that aerobic exercise improved vascular endothelial function to a greater extent in a hypoxic environment than in a sea-level environment.…”

Successive exposure to moderate hypoxia does not affect glucose metabolism and substrate oxidation in young healthy men

“…Rest or exercise under hypoxic conditions decrease body fat mass (Wiesner et al 2010), blood pressure (Schobersberger et al 2003), and arterial stiffness (Vedam et al 2009; Nishiwaki et al 2011) in various populations. Although several effects on metabolic and cardiovascular parameters have been proposed, the beneficial effects of hypoxic stimulation on glucose metabolism are especially attractive.…”

Effect of normobaric hypoxia on cardiorespiratory and metabolic risk markers in healthy subjects

“…PWV is generally assessed by measureing the time that the pulse wave takes to travel a given distance along the blood vessel; thus, it is an objective measurement of atherosclerosis. Nishiwaki et al [17] demonstrated a significant increase in the percentage of flow-mediated vasodilation and a significant reduction in PWV after training in the hypoxic group in postmenopausal women. Their results indicate that hypoxic training may induce vascular functional adaptation.…”

“…Meanwhile, new alternatives for traditional altitude training regimes have been proposed, known as "living low and training high", and the effects on endurance performance have been demonstrated extensively in athletes [10][11][12]. Recently, several studies have reported the effects of hypoxia training on physical fitness not only in athletes but also in nonathletes [13][14][15][16][17]. In obese subjects, body weight was significantly decreased in subjects with hypoxia training compared with that in subjects with normoxia training [14].…”

“…In obese subjects, body weight was significantly decreased in subjects with hypoxia training compared with that in subjects with normoxia training [14]. Recent studies have also reported that hypoxic training could more effectively reduce arterial stiffness in postmenopausal women compared with that in normoxic training [17]. However, although body weight changes during high-altitude mountain expeditions have been described in several studies for healthy subjects [18,19], there have been very few reports on hypoxic training effects under controlled experimental conditions.…”