BACKGROUND Altitude exposure causes acute sleep disruption in non-athletes, but little is known about its effects in elite athletes. The aim of this study was to examine the effects of altitude on two groups of elite athletes, that is, sea-level natives and high-altitude natives. METHODS Sea-level natives were members of the Australian under-17 soccer team (n=14). High-altitude natives were m...

Although we are far from a universally accepted pattern of impaired function at altitude, there is evidence indicating motor, perceptual, memory and behavioural deficits in adults. Even relatively low altitudes (2500 m) may delay reaction time, and impair motor function. Extreme altitude exposure (>5000 m) may result in more pronounced impairment that can persist after returning to the lowlands...

• Outline the effects of increasingly higher altitudes on (1) partial pressure of oxygen in ambient air, (2) oxygen saturation of hemoglobin in pulmonary capillaries, and (3) V O2max • Describe and quantify the oxygen transport cascade at sea level and at 4300 m • Discuss immediate and longer-term physiologic adjustments to altitude exposure • Give symptoms, possible causes, and treatment for a...

The benefits of living and training at altitude (HiHi) for an improved altitude performance of athletes are clear, but controlled studies for an improved sea-level performance are controversial. The reasons for not having a positive effect of HiHi include: (1) the acclimatization effect may have been insufficient for elite athletes to stimulate an increase in red cell mass/haemoglobin mass beca...

Introduction: Moderate altitude training has become popular to improve competition performance in swimming both at altitude and sea level. The aim of the present study was to examine the influence of moderate altitude training on lactate curve during three weeks and after the exposure to altitude training at 1860 m and to examine the effects of altitude training on selected blood parameters bef...

Fluctuations in autonomic cardiovascular regulation during exposure to high altitude may increase the risk of heart attack during waking and sleep. This study compared heart rate variability (HVR) and its components during sleep at low altitude and after 30 41 hours of acclimatization at high altitude (3480 m) in five mountain marathon runners controlled for diet, drugs, light-dark cycle and je...

Hypoxia or Oxygen deficiency, contributes significantly to the pathophysiology of many human diseases. High altitude is one such kind of environment where hypoxia is a major stress. The changes in the physiology at high altitude, whether short term or long term, help the successful survival of people from thousands of years. This suggests their adaptation to the adverse environment of high alti...

Decongestants and antihistamines are known to produce effects capable of adversely modifying physiological function and psychomotor task performance. Because of relevance to safe pilot performance, the effects of single doses of two decongestant-antihistamine preparations (Compound A and Compound B), or a placebo on cardiorespiratory responses to two equally spaced +2 Gz tests during separate 2...

We tested the hypothesis that exposure to altitude decreases reliance on free fatty acids (FFA) as substrates and increases dependency on blood glucose. Therefore, the effects of exercise, hypobaric hypoxia, and altitude acclimatization on FFA, glycerol and net glucose uptake and release [= 2(leg blood flow)(arteriovenous concentration)] and on fatty acid (FA) consumption by the legs (= 3 x gly...