Changes in heart rate, blood pressure, oral temperature and temperature of various parts of the skin such as the forehead, axilla, abdomen, forearm, fingertip and dorsum pedis were studied in the male athletes, male nonathletes, female athletes and female nonathletes before, during and after cold exposure (5°C, 10 minutes) .
1) Calculated body fat was greater in amount in the nonathletes, whereas the muscles of trunk and extremities were considered assumed to be better developed in the athletes. Harvard step-test score was higher in the athletes than in the nonathletes. So called athletic bradycardia was observed.
2) The heart rate decreased during cold exposure in all groups. However, there was no difference between the athletes and nonathletes.
3) The systolic and diastolic blood pressure increased during cold exposure in both the athletes and nonathletes, but extent was less in the athletes than in the nonathletes.
4) The oral temperature, taken as an index expressing the core temperature, showed no changes in either male athletes or male nonathletes. However, in response to cold exposure it increased slightly in female athletes whereas it decreased slightly in female nonathletes.
5) Temperature of the forehead, axilla, abdomen and forearm decreased in all groups in response to cold exposure. However, the decrease in the abdomen and forearm temperatures in the male athletes was significantly smaller than that of the nonathletes. The same tendency, though not statistically significant, was recognized in the abdomen and forearm temperatures between female athletes and female nonathletes.
6) There was a remarkable decrease in temperature of the fingertip and dorsum pedis in all groups during cold exposure. However, there was no difference between the athletes and nonathletes.
The above mentioned findings indicated that circulatry and peripheral-temperature response to maintain core temperature against cold were smaller in magnitude in the athletes than in the nonathletes, suggesting a better efficacy of the temperture regulation and stress adaptation mechanisms in the former.