[Increasing human heat tolerance by means of muscle training]

The experiments carried out on 129 athletes (gymnasts, weight-lifters and boxers) and 153 non-athletes have shown that sports training increases substantially the general and specific physical performance and elevates 2-2.5-fold the human resistance to thermal effects. The relationship between the signs of physical fitness of sportsmen and the values of their thermal resistance has been established. The procedure and scale of evaluating the thermal resistance of man have been developed.