Hot weather in Indiana is, let’s face it, frequent. On those hot and humid summer days, it’s brilliant. There’s great joy to be had in strolling around in the forest pretending you’re actually somewhere like the tropics.

But high temperatures and the burning sun also come with dangers. Heat exhaustion and the much more serious heat stroke can strike with surprising ease and rapidness – particularly if, like most, you’re not really used to it.

Perhaps because of our lack of familiarity with that big yellow ball in the sky, people’s grasp of the dangers posed by hot weather is not always perfect. We debunk some of the more popular myths and give you some tips to embrace the heat and sun safely.

Myth 1: The sun can’t harm me

From time to time we’ve all forgotten that the sun is still a gigantic ball of UV-emitting nuclear fire, even in Indiana. Some basic tips: a water-resistant or waterproof sunscreen is best as they won’t dribble off after five minutes of sweating uphill, but even these need to be reapplied eventually after enough perspiration. A hat with a wide brim will protect your face and shoulders and provide shade. For other clothing, think loose, light garments like zip-off summer trousers and long-sleeve button shirts.

In the long days of summer, early starts and late finishes with a shady rest during the heat of the day can be a simple way to enjoy the hills in peace and comfort. You also get to see more wildlife early and late because animals are far more sensible than we are.

Myth 2: You need to drink even when you’re not thirsty

For a long time, common wisdom among sports and fitness types held that if you become thirsty it was ‘too late’ – you were already suffering the effects of dehydration. Consequently it was best to drink continually during exercise. But in recent years the view seems to have shifted, with some physiologists arguing that distrusting your thirst in this way could even lead to drinking too much.

In truth, hydration needs will vary from person to person, and the best advice now seems to be drink when you’re thirsty.

No surprises there. But it’s easy to underestimate the amount of water you need in hot, windless weather. It’s prudent to take more water than you think you might need. As a guide, for the average person three litres or more is often not excessive for a big day in the hills when the heat soars.

Myth 3: Water is all you need to stay hydrated

In the movie ‘Anchorman’, Will Ferrell’s wayward newsreader Ron Burgundy famously lamented his choice of hot-weather beverage with the words: “milk was a bad choice.” It turns out he was wrong; semi-skimmed or low fat milk is actually a good re-hydration beverage in hot weather.

Okay, milk may not be the most practical choice for when you’re actually out on the hill a carton of curdled dairy product is no one’s idea of a refreshing beverage, but the reason why it’s a good choice are instructive. It has to do with its salt and mineral content. Sweating through exercise causes you to lose both water and things called electrolytes, which in layman’s terms basically means salt.

The term ‘dehydration’ is actually generally used to refer to both loss of water and electrolytes, both of which the body needs. It also needs them in the correct balance. Ever wondered why you get thirsty from eating salty foods? It’s because this balance has tipped too far in the direction of the electrolytes, and the body has to compensate.

Conversely, too much water without electrolytes is bad for the body too. For most backpacking activities electrolytes can often be kept up through food; a packet of peanuts nibbled on through the day in addition to your usual food, for example, will usually suffice.

Sports drinks and other products containing electrolytes of the sort used by runners and athletes are typically overkill, but in really hot weather it might be worth keeping one or two in reserve in case you become very dehydrated or start to feel the onset of heat exhaustion. Which brings us to our next myth…

Myth 4: Heat exhaustion and heat stroke are the same thing

Another common misconception is to mix up heat exhaustion and heat stroke. Both are indeed heat-related illness, but one is considerably more serious than the other.

Heat exhaustion is caused by water and electrolyte loss. It’s not a life-threatening condition in itself, but it can be a precursor to heat stroke, which is far more serious, if action isn’t taken. A few hours of strenuous exertion in the sun are enough to acquire the early symptoms of heat exhaustion, which include heavier-than-usual sweating, rapid breathing, nausea, a fast, weak pulse, light-headedness, and a feeling of being heavy, stultifying tiredness. Heat cramps, sharp pains in the abdomen arms and calves can also result. If you start to feel these, slow it down: top up your water and electrolytes, seek some shade, have a break, and adjust your pace.

If you don’t do the above, you could be at risk of heat stroke. Heat stroke is a serious, life-threatening emergency triggered by the body generating heat faster than it can shed it, causing core temperature to rise to dangerous levels. This in turn causes the brain to fail. Heat stroke can kill in as little as 30 minutes, so it’s vital you can recognize the symptoms and take action before it’s too late.

Signs of heat stroke include a very high body temperature (about 40C or above), a rapid, strong pulse, rapid breathing and muscle cramps. Very heavy sweating that suddenly stops is also a major warning sign.

Myth 5: If I have heat stroke I’ll be able to recognize it

A person with heatstroke may also be confused, irritable, restless or hallucinating, so by the time it strikes it will probably be up to others to take action. If you’re with a group, look out for each other and keep an eye out for signs that someone might be succumbing – very irrational or irate behavior is an easy-to-spot giveaway.

The first thing to do if you suspect someone of having heatstroke is to call for medical help – Mountain Rescue, if it’s available. In the meantime, move the victim somewhere cool, give them fluids to drink – preferably just water – and if possible cool their skin by placing wet clothing on it.

Myth 6: Swimming, it’s best to plunge in instead

Very few things in life are finer than a swim in a cool mountain tarn or river at the end of a sweltering day in the hills. But while it might be awfully tempting to leap straight in to that shimmering, sun-kissed water, such a drastic change in temperature can cause the body to momentarily shut down.

A safer bet is to ease yourself in gradually – even if it’s more painful – and avoid straying too far out into deep, cold bodies of water like lakes and reservoirs. Stay close to the shoreline, and don’t go out alone.