In recent times, an ingestible capsule sensor for the measurement of core body temperature has become available. This equipment was used to measure the relationship between core body temperature and daily living activities such as eating, exercise and bathing etc.
The main findings were as followings:
1. With respect to daily living activities, the core body temperature during bathing showed higher values in comparison with eating and light-grade exercise etc.
2. For the same-grade of exercise (HRmax60%) either in an environmentally controlled room at either constant temperature (25°C) and humidity (50%) or in water (36°C; 50%humidity), the core body temperature showed almost identical changes for peak value and the rise and fall ever time.
3. Atypical work at midnight was associated with a continuous decrease in core body temperature.
4. Atypical sleep in the daytime was associated with a continuous decrease in core body temperature.
5. For daily living activities inducing an increase in core body temperature, the correlation coefficient between core body temperature and heart beats/min was 0.87 (p<0.01).