For temperature studies, subjects must remain awake but calm and semi-reclined in near darkness while their rectal temperatures are taken continuously. Though variation is great among normal chronotypes, the average human adult's temperature reaches its minimum at about 05:00 (5 a.m.), about two hours before habitual wake time. Baehr et al. found that, in young adults, the daily body temperature minimum occurred at about 04:00 (4 a.m.) for morning types but at about 06:00 (6 a.m.) for evening types. This minimum occurred at approximately the middle of the eight hour sleep period for morning types, but closer to waking in evening types. COUNT 5
QSN1 What physical factor must be continuously monitored during temperature studies>  ANS1 temperatures QSN2 At what time does the average adult human reach his lowest temperature? ANS2 05:00 QSN3 How long before wake time is the lowest temperature reached? ANS3 two hours QSN4 When does the temperature of morning type young adults reach its lowest? ANS4 04:00 QSN5 What is the time of lowest temperature for evening type young adults? ANS5 06:00