Observations on the digital vascular hunting reaction to cold air exposure and measurements of physical characteristics were made among male university students: 88 non-athletic; 18 tall, lean non-athletic; 26 volleyball players. Experiments were carried out at about 3 p, m. in winter. The subjects sat at rest on a chair for 30 min in a room at 22°C and inserted their left hands up to the wrist with the palm downwards into a chamber at -10°C for 30 min. The skin temperature on the center of the dorsal surface of the distal phalanx of the left middle finger was recorded continuously starting at 5 min before the cold exposure. The physical status of volleyball players was characterized by large stature, a low body fat and long fingers, while that of tall and lean non-athletic subjects was characterized by light body weight, a low body fat, and long and slender fingers. In each group, the higher the temperature before cold exposure, the higher were the skin temperature at the first temperature rise during cold exposure and the mean skin temperature during cold exposure. The mean value of the finger skin temperature during cold exposure for volleyball players at a given value of skin temperature before cold exposure tended to be lower than those for non-athletes. The mean value of the finger skin temperature during cold exposure for volleyball players was lower than that for non-athletes. Among the non-athletes, tall and lean subjects showed a lower mean skin temperature during cold exposure. The skin temperature during cold exposure tended to be lower when the length of the finger was longer and the ratio of finger girth to length was smaller. The lower mean skin temperature during cold exposure for volleyball players might result from injuries and shocks to the finger received during volleyball training.

The present study was designed to examine the effects of aerobic exercise on the change of alpha wave component in electroencephalogram (EEG) and plasma β-endorphin. Exercise consisted of 30-min cycling on an ergometer with the load adjusted to elicit a heart rate rise of 50% between resting and predicted maximal value. The EEG signals and blood samples were obtained before and after 30-min exercise. The EEG signal was digitized at a sampling frequency of 64 Hz and analyzed by means of computer-aided decomposition algorithm and frequency power spectral analyses, respectively. The blood samples were immediately centrifuged for 15-min for quantitative analysis of β-endorphin by means of radioimmunoassay method. Results indicated that β-endorphin was significatly (p<.05) greater after exercise as compared to that of the resting contorol. It was also found that the larger the changes in β-endorphin following exercise, the higher the appearance rate of alpha wave in EEG. There was a positive and significant correlation (r=563, p<0.05) between the increase in alpha wave component and that of the plasma β-endorphin. These results suggest that traquilizer effects of aerobic exercise could be explained, at least in part, by the increase of alpha wave component and plasma β-endorphin which in turn bring about the relaxation effects upon the central nervous system.

The present study was designed to examine the effects of aerobic exercise on the change of alpha wave component in electroencephalogram (EEG) and plasma β-endorphin. Exercise consisted of 30-min cycling on an ergometer with the load adjusted to elicit a heart rate rise of 50% between resting and predicted maximal value. The EEG signals and blood samples were obtained before and after 30-min exercise. The EEG signal was digitized at a sampling frequency of 64 Hz and analyzed by means of computer-aided decomposition algorithm and frequency power spectral analyses, respectively. The blood samples were immediately centrifuged for 15-min for quantitative analysis of β-endorphin by means of radioimmunoassay method. Results indicated that β-endorphin was significatly (p<.05) greater after exercise as compared to that of the resting contorol. It was also found that the larger the changes in β-endorphin following exercise, the higher the appearance rate of alpha wave in EEG. There was a positive and significant correlation (r=563, p<0.05) between the increase in alpha wave component and that of the plasma β-endorphin. These results suggest that traquilizer effects of aerobic exercise could be explained, at least in part, by the increase of alpha wave component and plasma β-endorphin which in turn bring about the relaxation effects upon the central nervous system.