Most people don't get the recommended 7.5 hours of sleep to efficiently refresh themselves for the next day - which is why a sleep specialist revealed the seemingly perfect formula to getting a full nights sleep.

Michael Breus, a board-certified sleep specialist, told Yahoo Health that there is an "absolute right time to go to bed" to get sufficient sleep. 

In our fast-paced society, most Americans don't feel they are getting enough sleep. A Centers for Disease Control and Prevention survey found that 48 percent of adults say they aren't getting enough hours of shuteye at night. 

One sleep cycle is 90 minutes, and Brues said you should aim to get five of those every night - which would result in the targeted 7.5 hours of shuteye. 

His formula for ensuring you get all five sleep cycles in is fairly simple.

"Work backward from your wake-up time," Breus said to Yahoo Health. "That's socially determined by when you have to get up to get to work, get the kids ready, all those external factors." 

For example, if you have to be up at 5:30 a.m. your bedtime would be 10 p.m. - which is exactly 7.5 hours earlier than you should be getting up. 

"Follow that bedtime for 10 days in a row," Breus told Yahoo Health. "and you'll begin, quite naturally, to wake up a few minutes before your alarm clock sounds." 

Breus said he knows that some people feel that they just can't fall to sleep that early, but the sleep specialist believes this formula can work for anyone who is consistent with it. 

"It's all about the wake-up time," Breus told Yahoo Health. "I don't care if you can't fall asleep at 11 p.m. initially. If you are consistent about getting up at 6:30 a.m. every morning, your body will adjust." 

If you are sitll having difficulty getting a good nights sleep, Breus suggests setting a nighttime alarm a half hour before bedtime; if you work on a computer use the program flux, which makes the brightness on the computer adjust with the time of day; or getting yourself immediately into sunlight after waking up.