Why does heat make you sleepy

The brain detects a rise in blood temperature and causes the body to sweat and blood vessels to dilate to lose heat — these processes are active and require energy. She continues on to say that high outside temperatures and an increase in sweating can also result in a degree of dehydration, which in turn can leave you feeling lethargic.

Another couple of common reasons for drowsiness when the temperatures soar? If you've done a workout in the high heat, that could well be a contributing factor. Finally, many people struggle to fall or stay asleep in hotter temperatures, and we all know poor slumber makes you more tired the following day. Dr Brame has several helpful suggestions when it comes to clawing back some much needed energy and alertness:. Well, that all depends on the reason why you're tired in the first place.

Interestingly, she adds, we keep cooler at night when wearing PJs as sweat is wicked away from the skin by clothing — so going naked isn't actually the best solution. Opting for natural fabrics and taking a cool shower before bed will work wonders instead. Also - keep in mind that if you're feeling lethargic to the point of not being able to work, or socialise, it could indicate a more serious problem.

The signs of heat exhaustion include: having a headache, dizziness, nausea, excessive sweating and clammy skin. It works like this: When you become overheated, your body attempts to regulate any heat gain by sweating which, if you don't drink enough water, can make you dehydrated. And even mild dehydration can make you feel drowsy. The great news is that there are lots of ways to keep your energy up this summer. Wear loose—or better yet, very little—clothing to make sure your body can sweat and cool itself off efficiently.

But of course cover all exposed skin with a great sunscreen. And finally, if you start to feel like the heat is too much, stop heat exhaustion early by cooling off inside, in the shade, or in the water. To keep yourself from getting dehydrated, drink sufficient water to provide your body with the hydration it needs. The body has its own mechanism of keeping cool.

Through the sweat glands, the body gives out heat in order to keep cool and regulate body temperature. The body expends energy in order to keep cool, and the more we sweat, the more energy we lose, leading to fatigue and sleepiness. The same thing happens when we are engaged in any strenuous physical activity like running or lifting weights.

The purpose of sweating is to keep the body temperature consistent and prevent overheating. There are times when heat is actually comforting. Other instances, such as taking a warm bath or having a hot drink, also emulate this same effect, because after your body temperature rises, it starts to drop.

At the same time, overheating can also prevent you from a restful sleep. An overheated bed or mattress can prevent you from the sleep that you need.