...we sleep for about a third of our lives? A 70-year-old person has therefore slept for approximately 21 years, or 7.665 days, or 283.960 hours, or even 11.037.600 minutes. While we sleep the whole metabolism slows down: body temperature decreases for about one degree, blood pressure and hearth beat get reduced and all glands diminish their activity. Only the sweat glands increase their production. During one night an adult persons transudes about 0.3 litres of liquid. A person moves about 35-40 times/night. Adults sleep: on their back 44%, on their right side 32%, on their left side 18%, on their stomach 6%.