Slaves of the Slave System Plantation agriculture was wasteful, largely because King Cotton and his money-hungry subjects despoiled the good earth; quick profits led to excessive cultivation, or âland butchery,â which in turn caused a heavy leakage of population to the West and NW.
It means that since most adults need 8-9 hours of sleep, they will need about 1.6-1.8 hours of deep sleep to feel fully functional next day. However, the time of deep sleep is changed and that's mainly due to the change in the sleep need of different group of people. For instance: Age Group.
To do this, figure out what time you need to get up in the morning. Count back 7.5 hours as a good time to start getting to bed. 7.5 hours is a good benchmark because the average person goes through five 90 minute sleep cycles alternating between sleep (non-REM) and deep sleep (REM). It's best to wake in-between deep sleep cycles rather than in the middle of one.