Hypobaric hypoxia elicits several patho-physiological manifestations, some of which are known to be lethal. Among various molecular mechanisms proposed so far, perturbation in redox state due to imbalance between radical generation and antioxidant defence is promising. These molecular events are also related to hypoxic status of cancer cells and therefore its understanding has extended clinical...

R egular exercise is encouraged in patients with type 1 diabetes (1) and, indeed, the American Diabetes Association states that people with type 1 diabetes should be able to partake “in all forms of physical activity consistent with an individual’s desires and goals” (2). In keeping with this philosophy, increasing numbers of people with type 1 diabetes now participate in extreme forms of physi...

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...

BACKGROUND A growing number of subjects with diabetes take part in physical activities at altitude such as skiing, climbing, and trekking. Exercise under conditions of hypobaric hypoxia poses some unique challenges on subjects with diabetes, and the presence of diabetes can complicate safe and successful participation in mountain activities. Among others, altitude can alter glucoregulation. Fur...

The Tibetan Plateau, often called the roof of the world, sits at an average altitude exceeding 4,500 m. Because of its extreme altitude, the Plateau is one of the harshest human-inhabited environments in the world. This, however, did not impede human colonization, and the Tibetan people have made the Tibetan Plateau their home for many generations. Many studies have quantified their markedly di...

Extreme nature of climate and topographical conditions may affect soil properties at cold desert high altitude. Hence, the present investigation was undertaken to know altitudinal variations in soil physico-chemical properties at cold desert high altitude region. For this, agriculture soils were collected from different altitude viz. site I (1000011000 ft), site II (11000-12000 ft) and site III...

Hyperventilation is one of the most important features of acclimatization to high altitude. Resting ventilation at extreme altitudes increases up to fourfold and exercise ventilation for a given work level increases to the same extent. Hypoxic stimulation of the peripheral chemoreceptors is the chief mechanism for the hyperventilation but there is also evidence that central sensitization of the...

The ascent of Mount Everest (altitude 8,848 m) by two climbers without supplementary oxygen in 1978 was a feat that astonished many physiologists; indeed, measurements of maximal oxygen uptake at lower altitudes suggested that it would be impossible. Data obtained in 1981 at extreme altitudes, including the summit itself, showed that man can tolerate the extreme hypoxia only by an enormous incr...