Altitude training and muscular metabolism.

To study the effects of training at moderate altitude on muscle metabolism; we defined the lowest altitude which affected the aerobic capacity in man, and we studied the differences between training at an altitude of 2300 m and at sea level, both at the same relative (to the VO2max) and absolute intensity of work. We confirmed that at 1200 m the VO2max is decreased in sedentary and well-trained persons. Elite athletes already at 900 m decrease their VO2max. We have found an increase in myoglobin, oxidative enzyme activities and endurance capacity and a decrease in some glycolytic enzyme activities associated with simulated altitude training. We conclude that when the amount of training performed at altitude is similar to the amount at sea level, the stimulus of hypoxia associated with the training stimulus induces improvements in the muscle oxidative enzymes and myoglobin.