Studies on maximum aerobic power at simulated altitude, 2,300 m
It has been reported that maximum oxygen intake as an index of maxium aerobic power is decreased at high altitude as compared with sea level(Grover et al., 1967; Dill et al., 1966; Klausen et al., 1966). After the assignment of the 1968 Olympic Games to Mexico city(2,300m), the effect of elevation to 2,300m on physical working capacity as well as maximum oxygen intake was studied by many investigators(Lkai, 1967; Asshina, 967; Faulkner, 1967 & 1968; Saltin, 1966)and there was some variation in reduction of maximum oxygen intake and it was depend on the subjects' physical fitness (Buskirk et al., 1967; Saltin, 1966; Faulkner, 1967).
The present investigation was undertaken to evaluate the maximum aerobic power and the magnitude of reduction in maximum oxygen intake during the acute exposure to simulated altitude at 2,300m in nonathletes and athletes.
Eight non-athletes(college students for control) and Korean toprated 44 athletes (11 basketball players, 9 wrestlers, 7 boxers, 6 weightlifters and 11 women's volleyball players)selected for the Mexico Olympic Games, were chosen as subjects for this study. The maximum oxygen intake was measured by means of step-up test(Yoo et al., 1967, bench height 25cm) in non-athletes and of bicycle ergometer(Astrand, 1960) in athletes in sea level and low pressure chamber of which the pressure was
adjusted as low as the level of 2,300m altitude. The expired air was collected in Douglas bag through one way Douglas valve at final 30sec. during each work rate until maximum exhaustive exercise. The calculated maximum oxygen intake was corrected to standard temperature, pressure and dry.
The results may be summarized as follows:
1) Maximum minute ventilation (l/min) of athletes was greater than non-athletes at both sea level and high altitude. The values were slightly higher at the altitude than at the sea levels.
2) The maximum oxygen intake of athletes was relatively larger than that of non-athletes at both levels, and the percentage reduction of maximum oxygen intake in simulated altitude go sea level values of athletes was relatively larger(mean 17.2%) than that of non-athletes (mean 13.1%). Therefore, ventilatory equivalent was significantly increased in al subjects at high altitude.
3) The heart rate during maximum exhaustive work was about 190 beats/min in all subjects and was same as both the sea level and high altitude.
4) Reduction of oxygen pulse of the athletes was greater than that of non-athletes and the effect to altitude was large in the subjects having a good physical fitness.
It was concluded that maximum oxygen intake at 2,.00m altitude was decreased and the respiratory efficiency was reduced significantly in the Koreans.