Sleep and Recharge!

Sleep is an important part of your daily routine—you spend about one-third of your time doing it. Quality sleep – and getting enough of it at the right times -- is as essential to survival as food and water. Without sleep you can’t form or maintain the pathways in your brain that let you learn and create new memories, and it’s harder to concentrate and respond quickly.

Sleep is a state of reduced mental and physical activity in which consciousness is altered and certain sensory activity is inhibited. During sleep, there is a marked decrease in muscle activity and interactions with the surrounding environment.

Throughout your time asleep, your brain will cycle repeatedly through two different types of sleep: REM (rapid-eye movement) sleep and non-REM sleep.

The first part of the cycle is non-REM sleep, which is composed of four stages. The first stage comes between being awake and falling asleep. The second is light sleep, when heart rate and breathing regulate and body temperature drops. The third and fourth stages are deep sleep. Though REM sleep was previously believed to be the most important sleep phase for learning and memory, newer data suggests that non-REM sleep is more important for these tasks, as well as being the more restful and restorative phase of sleep.

As you cycle into REM sleep, the eyes move rapidly behind closed lids, and brain waves are similar to those during wakefulness. Breath rate increases and the body becomes temporarily paralyzed as we dream.

The cycle then repeats itself, but with each cycle you spend less time in the deeper stages three and four of sleep and more time in REM sleep. On a typical night, you’ll cycle through four or five times.

There are two main processes that regulate sleep: circadian rhythms and sleep drive.

Circadian rhythms are controlled by a biological clock located in the brain. One key function of this clock is responding to light cues, ramping up production of the hormone melatonin at night, then switching it off when it senses light. People with total blindness often have trouble sleeping because they are unable to detect and respond to these light cues.

Sleep works best when you set up a routine to allow it to work. Since the majority of adults need 7-9 hours of sleep per night, it’s important to plan when these 7-9 hours will take place. It’s also important to figure out how much sleep you need, since everyone’s sleep needs are different. This may require experimenting with your sleep schedule or discussing your sleeping patterns with a doctor in order to figure out how much you need.

Today, many people’s routines are not conducive to getting quality sleep. The light from electronic screens that we often use at night stimulates the brain rather than allowing it to ease into a state of restfulness. Plus, many people eat late meals or do significant amounts of physical or mental work late at night. These routines can disrupt your body’s natural rhythms and sleep needs, causing you to feel more run-down and affecting your body’s ability to function as it should. Here are some things you can do or avoid doing to improve your sleep.

Napping during the day can be an excellent, rejuvenating activity. However, napping for a long period of time can mess up your sleep schedule and cause you to have difficulty falling asleep and staying asleep. Try to only nap for 15-30 minutes at a time, as this will help you avoid falling into a deep sleep and messing up your chances of getting a good night’s sleep later on.

A bedtime routine is just as much about going to bed on time as it is about getting up early. For many people, getting up early requires them to practice a regular bedtime routine. This can include brushing your teeth, taking a shower, setting out the next morning’s clothing, preparing breakfast or lunch for the next day and doing other wind-down activities like reading or stretching. Turn off or set aside all electronics for 30-60 minutes before going to bed to allow your brain a chance to begin winding down, and opt for screen-free activities like reading, writing or drawing. It’s also important to set a specific time to go to bed and get up each day, as consistency in your sleep schedule will yield many benefits.

It takes nearly six hours for half of the caffeine from your favorite coffee, tea or cola to exit the body. Caffeine too late in the day can cause lighter, more disturbed sleep—or keep you from sleeping at all, researchers have found. In a 2013 study, researchers learned that consuming 400 mg of caffeine , six hours before bed cut total sleeping time by more than an hour.

There are many lifestyle changes you can make to help yourself get enough high-quality sleep on a regular basis.

• Be consistent: Going to sleep at the same time each night and waking up at the same time each morning can promote healthy sleep.

• Keep a bedtime routine: Practice a nightly routine of calm activities you engage in to prepare for sleep. This routine may involve dimming the lights and doing something quiet, like reading, for a couple of hours before bedtime.

• Avoid blue light at night: Stop using electronic devices, like smartphones and computers, at least half an hour before you plan on sleeping. These emit blue light, which suppresses melatonin, the sleep hormone.

• Exercise regularly: Exercising daily has been found to improve sleep quality and make falling asleep easier.

• Create a sleep-friendly bedroom: Keep your bedroom cool, dark, and quiet to improve sleep quality and duration. Ear plugs and blackout curtains may help.

Age and condition	Sleep needs
Newborns (0–3 months)	14 to 17 hours
Infants (4–11 months)	12 to 15 hours
Toddlers (1–2 years)	11 to 14 hours
Preschoolers (3–4 years)	10 to 13 hours
School-age children (5–12 years)	9 to 11 hours
Teenagers (13–17 years)	8 to 10 hours
Adults (18–64 years)	7 to 9 hours
Older Adults (65 years and over)	7 to 8 hours

References: John-Hopkins/Cleveland Clinic/Sleep Foundation