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Objective. To review the current literature that describes the effect of Antarctic residence on energy dynamics and aerobic fitness. Study design. Literature review. Methods. Published literature on energy dynamics and aerobic fitness in the polar environment was reviewed. Energy dynamics were represented by body weight, body fat, food intake and energy expenditure. Consideration was given to seasonal variation and possible explanations for the apparent high metabolic cost of Antarctic residence. The influence of cold exposure was discussed and comment was made on the differences between temperate and polar residence. Results. Food intake and energy expenditure are found to increase with Antarctic residence. There is often an associated increase in body weight and body fat. Seasonal variation is common but not universal, with an increase in body weight and body fat in winter. Variation in aerobic fitness appears to be related to the specific study sample rather than Antarctic residence per se. Conclusions. In most instances, Antarctic residence has effects on energy dynamics and aerobic fitness. Explanations for the observed changes may include physiological adaptations, such as a raised basal metabolic rate and increased thermogenesis. However, cold-induced changes are less likely when cold exposure is minimized by heated buildings and insulated clothing. Activity patterns related to work and leisure thus represent a more likely cause. The majority of the research is several decades old; further research would help to elucidate the patterns of energy dynamics of modern Antarctic workers. (Int J Circumpolar Health 2010; 69(3):220-235)

Ventilatory control undergoes profound changes on ascent to high altitude. We hypothesized that the fall in citric acid cough threshold seen on ascent to altitude is mediated by changes in the central control of cough and would parallel changes in central ventilatory control assessed by the hypercapnic ventilatory response (HCVR). Twenty-five healthy volunteers underwent measurements of HCVR and citric acid sensitivity at sea level and during a 9 day sojourn at 5200m. None of the subjects had any evidence of respiratory infection. Citric acid cough threshold fell significantly on ascent to 5200m. The slope, S, of the HCVR increased significantly on ascent to 5200m and during the stay at altitude. There was no correlation between citric acid sensitivity and HCVR. We conclude that the change in citric acid cough threshold seen on exposure to hypobaric hypoxia is unlikely to be mediated by changes in the central control of cough. Sensitivity to citric acid may be due to early subclinical pulmonary edema stimulating airway sensory nerve endings.

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