Physiological reactions of men and women during muscular activity and recovery in various environments

¹ Haskell Laboratory for Toxicology and Industrial Medicine, E. I. du Pont de Nemours and Co., Inc., Wilmington, Delaware

Men and women performing a standard exercise were studied in three environments. Pulmonary ventilation, O₂ consumption, CO₂ elimination, heart rate, blood pressure, body temperature and weight loss were recorded. Pulmonary ventilation was usually decreased in the warm-dry environment and increased in the warm-humid. Oxygen consumption was significantly lower in the warm-dry environment than at room temperature. The pattern of changes of these two functions was similar for both sexes. Respiratory exchange ratios were not influenced by sex, but were higher in the warm-dry environment. Increase in body temperature was found only in the warm-humid environment, with a smaller weight loss than in warm-dry conditions. Systolic blood pressure was influenced by work load but not by environments. Diastolic pressure varied little for both sexes under all conditions. Heart rate was significantly influenced by sex and environment, being highest for the women in the warm-humid conditions. Cardiac cost increased and cardiac efficiency decreased in both warm surroundings, more so for women than for men.