In this study, we examined changes in the amplitude of differential digital photoplethysmogram (ΔDPG) and the power spectral changes of EEG at rest during cold water immersion of the contralateral fingers (2°C), and after alcohol intake (0.3 g/kg) in 8 male subjects. This experiment showed that the ΔDPG amplitude decreased at rest and finger blood pressure was increased during the cold water stimulation, but there was no signifincant change in heart rate and EEG power spectrum. On chronological measurements for 30 minutes after alcohol intake, ΔDPG amplitude decreased slightly and finger blood pressure increased. Heart rate also tended to increase, and the alpha 1 power (8.0-9.8 Hz) on EEG gradually increased. The ODPG and finger blood pressure responses to cold water stimulation every 10 minutes was decreased after alcohol intake, whereas heart rate was not affected. However, a decrease in the alphal power after stimulation was revealed. From these results, it may be concluded that during 5-10 s of cold water stimulation, increased skin sympathetic nerve activity was one of the factors that raises blood pressure.

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The purpose of this investigation was to determine the effects of daily walking on aerobic work capacity, vital age and other fitness components in middle-aged and elderly walkers. The subjects were thirty-six walkers (average 65.0±8.0 yr, 51-80 yr), whose training period averaged 13.5±9.0 yr. The walkers were significantly greater in maximal oxygen uptake (VO₂max), and oxygen uptake at the lactate threshold (VO₂LT), and were 6.5 yr younger in vital age (VA) than sedentary middle-aged and elderly. These findings suggest that middle-aged and elderly walkers have more favorable profile of aerobic work capacity and of health status when compared to sedentary persons.

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