AIM Hyperbaric hyperoxia (HBO) is known to modulate aerobic metabolism, vasoreactivity and blood flow in the brain. Nevertheless, mechanisms underlying its therapeutic effects, especially in traumatic brain injury (TBI) and stroke patients, are debated. The present study aimed at investigating regional cerebral blood flow (rCBF) distribution during acute HBO exposure. METHODS Regional cerebra...

Richardson, R. S., H. Wagner, S. R. D. Mudaliar, R. Henry, E. A. Noyszewski, and P. D. Wagner. Human VEGF gene expression in skeletal muscle: effect of acute normoxic and hypoxic exercise. Am. J. Physiol. 277 (Heart Circ. Physiol. 46): H2247–H2252, 1999.—Vascular endothelial growth factor (VEGF) is involved in extracellular matrix changes and endothelial cell proliferation, both of which are pr...

Background and Aim: Apoptosis is a type of programmed cell death occurring by a series of intercellular messages which is associated with tissue structure remodeling. The purpose of the present study was to investigate the interactive effects of reducing exercise intensity and Adiantum capillus veneris extract on remodeling and modulation of pulmonary apoptotic indices of the rats exposed to th...

Hyperoxia has been shown to attenuate the increase in pulmonary artery (PA) pressure associated with immersed exercise in thermoneutral water, which could serve as a possible preventive strategy for the development of immersion pulmonary edema (IPE). We tested the hypothesis that the same is true during exercise in cold water. Six healthy volunteers instrumented with arterial and PA catheters w...

We have previously demonstrated that aging reduces the compensatory vasodilator response during hypoxic exercise due to blunted nitric oxide (NO) signaling. Recent evidence suggests that NO bioavailability can be augmented by dietary nitrate through the nitrate-nitrite pathway. Thus we tested the hypothesis that acute dietary nitrate supplementation increases the compensatory vasodilator respon...

We investigated whether the greater degree of exercise-induced diaphragmatic fatigue previously reported in highly trained athletes in hypoxia (compared with normoxia) could have a contribution from limited respiratory muscle blood flow. Seven trained cyclists completed three constant load 5 min exercise tests at inspired O(2) fractions (FIO2) of 0.13, 0.21 and 1.00 in balanced order. Work rate...

To evaluate the effect of intermittent hypobaric hypoxia combined with sea level training on exercise economy, 23 well-trained athletes (13 swimmers, 10 runners) were assigned to either hypobaric hypoxia (simulated altitude of 4,000-5,500 m) or normobaric normoxia (0-500 m) in a randomized, double-blind design. Both groups rested in a hypobaric chamber 3 h/day, 5 days/wk for 4 wk. Submaximal ec...

The aim of this study was effect of a single session of weight-lifting exercise on serum testosterone and cortisol and testosterone-cortisol ratio changes in elite weight-lifter of Mazandaran state. 10 elite weight-lifter of Mazandaran state was selected randomly. Moderate-intensity exercise was contained stand snatch (2 sets with 3 repeats of 60 one repeat maximum), Olympic snatch (2 sets with...

It is well-established that different altitude training modalities can improve convective oxygen (O 2) transport capacity and physical fitness of athletes (Millet et al., 2010). Exercising in hypoxia also induces specific muscular adaptations including increased oxidative enzymes (e.g., citrate synthase) activity, mitochondrial density, capillary-to-fiber ratio, and fiber cross-sectional area (...

Many avian species exhibit an extraordinary ability to exercise under hypoxic condition compared with mammals, and more efficient pulmonary O(2) transport has been hypothesized to contribute to this avian advantage. We studied six emus (Dromaius novaehollandaie, 4-6 mo old, 25-40 kg) at rest and during treadmill exercise in normoxia and hypoxia (inspired O(2) fraction approximately 0.13). The m...