Physical activity and the incidence of acute mountain sickness in United States Antarctic Program participants following rapid transport to the South Pole: Antarctic Study of Altitude Physiology (ASAP).
Ceridon-ML; Anderson-PJ; Miller-AD; Beck-KC; OMalley-KA; Johnson-JB; Johnson-BD
FASEB J 2010 Apr; 24(Meeting Abstracts):990.14
Background: Physical activity has been proposed as a risk factor for altitude illness however it is unclear whether the total amount or intensity of activity determines illness. Purpose: To examine activity patterns relative to the incidence of acute mountain sickness (AMS) in United States Antarctic Program workers rapidly transported to the South Pole (SP, 9303 ft). Methods: 53 medically screened subjects (age=37±10yr, BMI=24±3 kg/m2) were transported by a 3 hour flight from McMurdo Station (sea level, SL) to the SP. Physical activity was monitored at SL and for 3 days after ascent using BodyMedia® activity monitors. Symptoms of AMS were assessed using Lake Louise Questionnaires. Results: 53% of subjects displayed AMS between SP days 1-3 (23% day 1, 43% day 2, 15% day 3). Energy expenditure at SP was 3414±944, 3458±781, & 3543±869 Calories/day for days 1-3, respectively. Steps/day at SP was 12593±4926, 13124±4392, & 12966±4482 for days 1-3, respectively. Overall, more activity at higher intensity (>3 METS) on SP day 1 was associated with higher AMS incidence the next morning (p<0.05). Also, calorie expenditure with activity at >3 METS and time of activity at >6 METS in the first 24 hours after ascent independently increased the odds of AMS on SP day 2 (p<0.05). Conclusions: With rapid transport to altitude, moderate to intense activity within the first 24 hours of ascent contributes to the incidence of AMS.
Biological-effects; Biological-factors; Biological-monitoring; Biological-systems; Exposure-assessment; Physical-exercise; Physical-reactions; Physical-stress; Physiological-effects; Physiological-factors; Physiological-measurements; Physiological-response; Physiological-testing; Physiology; Statistical-analysis
Issue of Publication
The FASEB Journal. Experimental Biology 2010, April 24 - 28, 2010, Anaheim, California