Physiological adaptations and activity recorded at a polar base

Summary

Physiological parameters and activity were recorded monthly on 19 men wintering at a polar base. A comparison was made between those in their first Antarctic winter (Group A,n=13) and those in their second consecutive Antarctic winter (Group B,n=6). Group A were more active (p<0.001) and spent more time outside (p<0.001) during the summer months than during the darker and colder winter period. Combined data showed no correlation between total activity and meteorological conditions, but a clear (p<0.001) negative correlation with time spent outside and wind speed. In the first part of the year group A became fitter (as shown by a lower heart rate at a$\dot V_{O_2 }$ 1.51min⁻¹), increased basal oxygen uptake under standard conditions and put on body and fat mass. These changes were not demonstrated in group B living and working under identical conditions. Lean body mass of both groups rose throughout the year (A,p<0.001; B,p<0.05). These data suggested that the changes in physiological parameters in group A were in response to the life style and activity of a polar base, rather than to the Antarctic climate per se.