5 Reasons the Heat Makes You Sleepy - Best Mattress
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5 Reasons the Heat Makes You Sleepy

Don’t you just love going on a outing outside with friends and family? We love being around those we care about especially outside in nature. After a long day outside we usually feel beat. We forget how worn out we feel when we get home from being out in the sun all day. Our bed is calling our name and usually we just want to take a long nap. There are actually scientific reason that explain the tired after the sun feeling that most of us experience. Let us shed some light on this phenomena.


Often, it’s not the heat itself making you tired, but the dehydration that comes with it. Losing fluid and salt through sweating can quickly lead to dehydration, which usually lead to tiredness. When you feel thirsty, you’ve already lost 2 to 3 percent of your body fluid. Even this mild dehydration can make you feel tired or lethargic. Your blood volume lowers, which means you don’t get as much blood to your brain and your heart has to pump harder.

Trying to keep cool

Scientists say that energy from the sun transfers heat to the body through electromagnetic radiation in the form of photons. This radiation causes body temperature to increase. When your body temperature changes more than .5 degrees, your body reacts by being sleepy, grumpy, or tired. While we are out in the sun, our body has to work hard to regulate our body temperature. Similar to the above reason, your body will expend energy in an attempt to keep cool. Sweating is just one of these ways.

Heat tricks your brain

Sometimes the fatigue doesn’t set in until after you’ve removed yourself from the sun. If you spent a large amount of time outside, the transition back indoors can cause an exhaustive effect. Depending on how dark your indoor environment is, the contrast from sunlight to indoor lighting can trick your brain into thinking it’s time for sleep, kickstarting your melatonin production.

Your body is experiencing chemical changes

It’s no secret that the sun’s ultraviolet rays can penetrate the skin and cause damage (such as sunburn, pigmentation changes, and wrinkles). The cascade of chemical changes that produce these effects can also cause fatigue after hours in the sun. The more time you spend in the sun, the sooner your body starts working to fix the damage done, resulting in fatigue.


Out in the sunlight, the sleep/wake cycle is interrupted. The sun sends signals that change the day/night rhythm. Exposure to the sun can reset your clock. Our bodies believe that day is awake and night is for sleeping. People who don’t get enough sunlight often suffer from insomnia.

Tips to avoid heat fatigue

Follow the below tips to avoid heat fatigue. Not only will they prevent you from getting tired,they’ll also help you avoid some of the other consequences of spending too much time in the sun.

  1. Stay in the shade when you can– The best way to avoid heat fatigue and dehydration is to stay out of the sun. You’ll still get plenty of benefits simply from being outdoors, but you won’t get as hot.
  2. Stay hydrated– The bestway to avoid dehydration is by staying hydrated. Makes sense, right? Bring along a refillable water bottle and know where your closest drinking fountains are. Eat foods that have a high water content, such as fruits and veggies. However liquids that are a diuretic, such as alcohol, will only increase your dehydration.
  3. Eat salty snacks– When you sweat, you not only lose water, but also salt and other electrolytes, so eating salty snack such as pretzels or nuts will keep you better hydrated as well.
  4. Take breaks– When you’re engaged in physical activity outside, it’s important not to overextend yourself. Your body is already working harder than normal to maintain your body temperature.

When you just can’t seem to avoid feeling tired and you just want to crash, Best Mattress can help. After spending a long, fun filled day in the sun wouldn’t it be nice to sleep on a mattress that you feel is made just for you? We’ve got you covered!