Timing and amount of sleep determine how rested you feel

Did you sleep well last night? Or did you wake up feeling fatigued and sluggish — perhaps even wondering if you really slept at all?

Getting a good night's sleep requires more than crawling into bed and closing your eyes. Understanding your sleep behavior and preparing for a sound slumber can help make sure every night is a good night for sleeping.

"Sleep is a behavior and, like all behaviors, it varies greatly among people," explains Dr. Carol Landis, sleep researcher and associate professor in biobehavioral nursing and health systems at the School of Nursing.

"The greatest differences occur in the timing of sleep and the amount of sleep — the factors which are most important in determining whether you will wake up feeling rested."

Research has found that people sleep better at different times during their daily cycle. For example, some people function better if they go to sleep early and rise early, while others feel more rested if they stay up late and sleep in.

"Many people don't pay attention to the timing of their sleep," Landis notes.

"Yet delaying or altering the time you go to sleep can have a major impact on how you feel when you wake up."

The amount of sleep the average adult needs each night also varies. Some people may be fine with six hours sleep, while others need up to nine hours per night. Landis points out that those who follow a regular sleep schedule are more apt to function better on fewer hours, but she adds that most adults need at least six hours of sleep each night.

Work schedules and other commitments can make it difficult for many to follow their optimal sleep pattern. While employees may clock in at the same time, some may be more productive working later or earlier in the day.

"Unfortunately, most people don't have the flexibility to set their own working hours," Landis says. "We haven't found a good way to integrate these issues of sleep timing to make them optimal for humans to function."

So what can a person do if their work schedule can't be changed? Fortunately, while sleep behavior is variable, it is also modifiable.

"A person's sleeping patterns aren't set in concrete," Landis stresses.

Gradually altering the timing of sleep can help change sleep patterns. An "evening person" who needs to get to work early in the morning can try upping the time they go to bed by 30 minutes every few days. Within a few weeks, this slow adjustment will help "reset" the internal body clock. Light therapy and melatonin can also be helpful in adjusting sleep timing.

In addition to maintaining a regular daily sleep schedule, Landis offers the following tips on practicing good sleep hygiene: