How to cope in the outdoors with a heatwave

What temperature is considered a heatwave?

The Met Office defines a heatwave as "an extended period of hot weather relative to the expected conditions of the area at that time of year, which may be accompanied by high humidity". In other words, it's hotter for a longer period of time than you would expect, for where you are.

The World Meteorological Organisation states that a heatwave is when the daily maximum temperature is higher than the average maximum temperature by 5°C for five or more consecutive days. Thresholds for UK heatwaves vary by county.

Why it's important to stay cool during a heatwave

Dr Ross Perry, GP and medical director of Cosmedics, says that staying cool and taking precautions during a heatwave are important, as experiencing heat exhaustion for an extended period of time can lead to heatstroke. The symptoms of heat exhaustion include:

• Feeling sick.

• Dizziness.

• Feeling faint.

• Confusion.

• Cramps.

• Feeling thirsty.

Dr Perry adds that swollen fingers, toes, hands, and feet are common following exposure to heat, as it causes swelling (heat oedema). This swelling tends to be no cause for alarm, but you can ease symptoms by taking breaks from the sun and drinking plenty of water.

How to keep cool outdoors in a heatwave

Seek out the shade

Since sunny days are few and far between, it can be tempting to bask in those golden rays all day long when they do make an appearance. However, it's all about balance. Spending time in the shade offers a multitude of benefits, as well as reducing your risk of heatstroke:

• Prevents skin from dehydrating.

• Prevents hair from becoming burnt, brittle, and faded in colour.

• Prevents dry eyes worsening due to the glare of the sun.

• Prevents chapped lips.

• Reduces risk of skin cancer, brown spots, and visible red veins.

• Reduces risk of heat rash.

Remember to wear sunscreen

No one is too cool for sun cream - it is essential in protecting your skin from the sun's harmful UV rays, even on cloudy days. It is recommended that you wear an SPF (sun protection factor) of 30 or above while keeping an eye out for any changes in your skin throughout the day. Ideally, children and those with highest risk of skin cancer should be using SPF of 50 or more. Not only does sunscreen reduce your risk of skin cancer, it also prevents early signs of ageing, reduces inflammation, prevents skin discolouration, and, of course, reduces risk of sunburn.

It's recommended that you reapply roughly every two hours, depending on the specific sun cream and SPF you're wearing, and use a water-resistant product.

Don't overdo the exercise

A light jog on a sunny day might sound idyllic, but don't go overboard because exercising while it's hot puts extra stress on your body. The combination of exercise and the humidity can increase your core body temperature, with you having more blood in circulation as an attempt to cool down. If you are going to be exercising and sweating in the heat, sunscreen is even more vital.

And remember to reapply frequently - every 40 minutes - if you are sweating, swimming, or drying off.

Stay hydrated

Remember to keep refilling your water bottle too, since your body loses fluids by sweating as well as breathing faster when you feel hot.

You should be drinking at least eight glasses of water over a normal day. This should be more when its hotter. Don't wait until you feel thirsty to grab a drink - keep filling up your glass at regular intervals. If you're out and about, take a water bottle with you - you can buy insulated bottles that will keep your drinks cold. On hot days, you should steer clear of caffeine and try to reduce alcohol consumption, as these can dehydrate you more.

What to wear in a heatwave

Items you should have in your summer wardrobe to protect against heat include:

• Light-coloured loose clothing to protect against permanent skin damage.

• A wide-brimmed sun hat - at least 7.5 cm - to cover your face, head, and neck.

• Sunglasses - to protect your eyes from the harmful effects of UV rays.

How to ease sunburn

If you do end up getting sunburnt, there are ways of easing it.

"What sunburnt skin needs more than anything is intensive moisture; therefore, any intense moisturiser will do the job. A moisturising after-sun containing aloe vera is a good choice, as it combines the soothing benefits of aloe vera with hydration. Above all, the key is to apply liberally and frequently, every hour or so, if necessary," explains Dr Perry.

Top tip: keep your moisturiser in the fridge and it will instantly cool hot and itchy skin when applied.

There is also anecdotal evidence supporting the use of natural aloe vera as a traditional herbal remedy for sunburn symptoms, with some people crediting its cooling and soothing feeling. However, there is no scientific evidence for this.

Other tips for easing sunburn include using a cold compress to relieve inflammation - which you can use every hour throughout the day.

So, whatever you get up to this summer, be safe and have fun!

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