When school's out, temperatures are high and ice cream truck anthems are playing on an endless loop, a new set of seasonally specific sleep considerations come into play. From escaping the heat to making time for time-off, here are eight commandments to guide your summer of sleep.
1. Don't let hot nights become sleepy days
Hot weather not only makes it hard to sleep it at night; it also leaves some people fatigued during the day. In one study, researchers surveyed participants about their fatigue levels in July, August and September. They found that hotter days corresponded to more fatigue — but only for participants with existing sleep problems. Good sleepers, on the other hand, maintained the same level of fatigue, regardless of the temperature.
And, across the board, research suggests that temperature and sleep quality have an inverse relationship — as temperatures rise, sleep quality dips. Experts recommend keeping your bedroom between 65 and 70 degrees. Obviously, cool sleep environments are harder to come by in the summer. But, even if you don’t have AC, there are plenty of ways to keep the sweats at bay. For instance, consider placing a bowl of ice in front of a fan for a DIY cooling system. Or try one of these 11 other tips.
2. Stay cool and keep your cool
In his 1942 novel the The Stranger, Albert Camus shed light on the impact of heat on a person's psychological state. And it seems like the French existentialist was onto something; there's scientific evidence that temperature can influence how we feel and behave. Higher temperatures, in particular, have been associated with increased aggression. In a study involving NFL football players, warmer weather led to more violence, as measured by penalties committed during games.
And, while sleep, aggression and temperature haven’t explicitly been linked, researchers have found a significant association between high levels of hostility and subjective sleep quality.
One study, for instance, found that the more hostile the individual, the worse they slept at night. In this case, poor sleep was characterized by difficulty falling asleep, poor sleep quality and high levels of tension. So, as you head into the dog days of summer, remember that age-old saying: Love thy neighbor and you’ll both sleep better.
3. Stick to the status quo
Summer tends to be a time of year when responsible bedtimes fall by the wayside, especially for kids. Unlike adults, most of whom fall somewhere in the middle of the lark-to-owl scale, kids are generally morning-oriented. Nonetheless, their bedtimes drift later during the summer. This probably has something to do with the disproportionate number of evening activities that crop up during the warm months, from sunset Little League games to moonlit movie nights. But, despite the shift in bedtime preference, it’s best to keep kids' sleep schedules as close to normal as possible.
4. Seize the solstice
The Summer Solstice (aka the official start of summer) takes place on June 21. And, even though nighttime fun can make it hard to hit the sack on time during the summer, the sweaty season is actually a good time to get your sleep back on track.
Light has an enormous impact on sleep. In one study, for example, office employees who were exposed to high levels of light in the morning fell asleep faster at night, as well as had more synchronized circadian rhythms and better sleep quality, than participants exposed to low levels of light. (The morning-light group also experienced reduced depression.)
Our body clocks are supposed to sync up with daily patterns of light and darkness. But many of us are slightly out of sync. Fixing this misalignment typically requires manipulating our exposure to light. And this is easier to do in the summer than the winter because it's easier to block out light (hey, blackout shades) than it is to create fake bright light that mimics the natural stuff.
5. Mind the mood-altering impact of light
Could mania, a mental illness marked by euphoria, overactivity and delusions, be seasonal? Well, according to a review paper, many studies have reported that bipolar patients experience more mania during the summer months and more depression during the winter months. The underlying mechanism is thought to be hypersensitivity to light. This ramps up suppression of the drowsiness-causing hormone melatonin, which, in turn, leads to increased alertness and hyperactivity. Two bipolar treatments, lithium and valproate, can work to mitigate these seasonal swings by increasing melatonin production and stabilizing circadian rhythms.
6. FNE happens. Move on
Your hotel room seems primed for a great night’s rest: It’s quiet, dark, cool and equipped with the type of plush, expensive bedding you’d never buy yourself. But, for some reason, you have trouble falling, and staying, asleep when turn-down service is on the menu. At least you're not the only one. In the sleep world, this strange phenomenon is called the “First Night Effect” (FNE).
You feel uneasy on night number-one because your body is trying to stay vigilant in an unfamiliar environment. Your brain is divided into two hemispheres: left and right. On the first night, the two hemispheres take turns staying “awake." And this half-awake state is thought to be a protective mechanism that lets you detect any deviant noise and become alert at a moment’s notice. Although there’s not much we can do to avoid FNE, it can be comforting to know that researchers consider it a “typical sleep disturbance.”
7. Switch your status to OOO
Think of FNE as a hump to power through. Because, once you get over that initial night of rocky rest, being on vacation will most likely help you rest easy. Studies have shown that vacationing for more than two weeks comes with positive health outcomes, including reduced fatigue, better moods and higher-quality sleep. Researchers aren’t sure, however, if taking time off improves your mood, which leads to better sleep, or if being on vacation lets you get the sleep you need to exude positivity.
Does it matter what kind of vacation you take? For the sake of your sleep, it wouldn’t hurt to spend some time in the great outdoors. There’s evidence that real nature sounds are more relaxing than fake white noise. This is the case, researchers believe, because it takes less brain power to process natural environments than man-made ones.
So set your Slack status to “Out Of Office,” tell your boss you’ll be back in a fortnight and go find a babbling brook to fall asleep next to.
8. Stretch it out
Nocturnal leg cramps, also called rest cramps, are painful, involuntary muscle contractions in your legs or feet. And, during the summer months, according to one study, quinine prescriptions (to treat the pain) and internet searches for leg cramps are almost double what they are in winter months. To researchers, these findings suggest a summertime uptick in cramps. At this point, it's not clear why summer is the season for cramping. But stretching your muscles before bed, taking a warm shower and drinking plenty of fluids can help ease the pain.