Relationship of Activity Patterns to Acute Mountain Sickness in South Pole Workers

Abstract

This study aimed to evaluate the influence of physical activity on incidence of acute mountain sickness (AMS) by continuous activity monitoring in a free-living sample of South Pole workers over the initial 72 h at altitude exposure of 2,840 m (9,318 ft). Body Media activity monitors were worn by 47 healthy participants. AMS was defined by the Lake Louise symptom questionnaire. Venous blood samples were taken at sea level and approximately 48 h after high altitude exposure. AMS incidence was 34% (n=16/47) over the first 48 h and 40% (n=19/47) over 72 h. On day 2 at high altitude, individuals with AMS demonstrated a significantly greater increase in the percent change in physical activity metrics from baseline: total energy expenditure 19±13 vs. 5±7%, total steps 65±51 vs. 10±18%, metabolic equivalent of tasks 21±13 vs. 7±13%, and time spent performing moderate to vigorous physical activity 114±79 vs. 26±27% for individuals with AMS vs. no AMS, respectively, p<0.05. In addition, erythropoietin and vascular endothelial growth factor were 1.69 and 1.75 times higher, respectively, in those with AMS. In conclusion, workers who engaged in increased physical activity and activity intensity during initial exposure to the South Pole were more susceptible to developing AMS.

Human psychophysiology in Antarctica

“…The earth's spin and cold air caused by the Ferrel cell wind belt alter the barometric pressure to be lower than what would be expected at the physical altitude of the South Pole altitude. [29] Many Antarctic stations are located near the South Pole and are at a considerable altitude above sea level. Life is more stressful in such stations than at Antarctic seashores or near sea level.…”

“…[31] Physical exertion due to extensive outdoor work in extreme cold increases AMS incidence significantly in the polar regions. [29] Using oral contraceptive pills increases the risk of developing AMS. [32] Researchers reported increased hematocrit, thrombocyte, lymphocyte, granulocytes, and monocytes while staying in the French-Italian Concordia station.…”