Ten years of "civilization": fitness of Canadian Inuit.

Data on the cardiorespiratory fitness of the Canadian Inuit has been obtained before and after 10 yr exposure to "white civilization." The population tested comprises 201 males (aged 9-76 yr) and 143 females (aged 10-69 yr), about 70% of the eligible population of Igloolik (69 degrees 40'N). During direct maximum tests to exhaustion, a higher maximum heart rate was attained in 1980-81 (194.4 beats X min-1) than in 1970-71 (184.5 beats X min-1); this probably reflects a closer approach to a centrally limited maximum as the Inuit have become familiar with white investigators. The Astrand nomogram currently underestimates the directly measured maximum O2 intake (VO2max) by some 3% in subjects making a good maximum effort. Comparing the 1980-81 data with results for 1970-71, there has been a 15% decrease of predicted VO2max, accompanied by a 2- to 4-kg increase of body mass, accumulation of subcutaneous fat, and a decrease of leg extension strength, these changes affecting all subjects except boys aged 9-15 yr. It is suggested that the loss of personal fitness is related to adoption of a more sedentary lifestyle, particularly the use of tracked vehicles in place of walking through deep snow.