How many hours of sleep do you get each night? The National Sleep Foundation conducted a Sleep in America Poll in 2020 and found that more than one-third of adults in America are not getting enough sleep and feel sleepy during the day for at least half the week or more. Survey participants felt as if feeling tired affects their work performance, ability to exercise, and negatively affects their relationships with friends and family. Sleep affects almost every type of tissue and system in the body—from the brain, heart, and lungs to metabolism, immune function, mood, and disease resistance. Research has shown that a chronic lack of sleep, or poor-quality sleep can increase the risk of high blood pressure, cardiovascular disease, diabetes, depression, and obesity.
There are two stages of sleep: Rapid Eye Movement (REM) and Non-Rapid Eye Movement (NREM)
REM sleep is a more “wakeful” state of sleep.
• Heart rate and blood pressure increase to levels similar to what you experience when you are awake.
• Eyes move rapidly darting back and forth under your closed lids.
• Muscles become temporarily paralyzed- prevents you from acting out your dreams
• Most of the dreaming occurs simultaneously
NREM has three parts three parts: starting to fall asleep, light sleep, and deep sleep
Stage 1 Sleep is shifting from wakefulness to sleep.
• Short Period lasting several minutes
• Heartbeat, breathing, and eye movements slow, muscles relax with sporadic twitches.
• Brain waves begin to slow from their daytime wakefulness patterns.
Stage 2 Light sleep before you enter deeper sleep.
• Your heartbeat and breathing slow, and muscles relax even more.
• Body temperature drops, and eye movements stop.
• Brain wave activity slows, brief bursts of electrical activity.
• More repeated sleep cycles spent in this sleep than in other sleep stages.
Stage 3 Deep sleep
• Longer periods during the first half of the night.
• Heartbeat and breathing slow to their lowest levels during sleep.
• Muscles are relaxed, and brain waves become even slower.
• Energy is renewed
On a regular night your sleep rotates through periods of REM and NREM sleep approximately every 90 minutes. In an ideal world, you want to get five or six full sleep cycles, which equal seven and a half to nine hours of sleep each night.
• REM stage accounts for approximately 25 percent of sleep time
• NREM stage takes up the other 75 percent sleep time.
How Much Sleep Do You Need?
The National Sleep Foundation (NSF) recommends the following:
• 0-3 months: 14 -17 hours of sleep- includes daytime naps.
• Older infants 4-11 months- 12 to 15 hours of sleep each day.
• 1-2 years 11 -14 hours of sleep each night.
• Preschoolers 3-5 years 10 to 13 hours each night
• School-age kids 6-13 years 9 to 11 hours each night.
Teenagers: As kids get older, their need for sleep decreases
• Teens 14-17 years 8 to 10 hours of nightly sleep.
• 18 and 64 7 to 9 hours of nightly sleep
• 65+ seven to eight hours of nightly sleep
Approximately one-third of adults in the U.S. nap daily; men more than women. Research has found that nap time decreases daytime sleepiness, boosts learning and performance.
• Helps you feel refreshed and ready to meet the daily demands.
• Improves your mood and energy levels.
Researchers found napping for 20 minutes allows your mind and body to rest without going into the deeper stages of sleep. Longer naps for 60 to 90 minutes allows time to have deep, slow wave sleep and ends up in the lighter stages of sleep so you feel alert when you wake up. Medium length naps around 45 minutes can be challenging because you probably wake up during slow wave sleep, which is the deepest stage. This will leave you feeling groggy when you wake up.
Research has found that people who nap for approximately 30 minutes had better memory recall and superior overall cognition than those that don’t and those who nap for long periods of time. NASA tested the effects of power naps on astronauts and found positive effects on performance and alertness. Power Naps taken in the early afternoon for approximately 15-20 minutes can rejuvenate you when feeling a decrease in energy and wakefulness.
• Find a cool, quiet, dark place for napping, think about using an eye mask and ear plugs
• Napping before 2pm so it does not affect your nighttime sleep
• Drinking a small amount of caffeine before your nap may help you avoid feeling groggy when you wake up
• Days you can’t get a nap in; getting out in bright sunlight can help restore energy
• Set an alarm to avoid sleeping more than 20 minutes