How to exercise safely in the heat: Fitness experts share their top tips

Independent

29-05-2025

Exercising outdoors provides benefits such as fresh air and vitamin D. However, as summer nears, safety precautions are essential.
Exercising in the heat can lead to dehydration and heat exhaustion, especially for beginners and older adults. Avoiding peak sun hours and seeking shade are advisable.
Listening to your body and taking breaks are crucial to prevent overheating and exhaustion.
To help you stay safe while staying active, we spoke with fitness experts who shared their top tips for exercising safely outdoors this summer.
Acclimatise
'A lot of people jump straight into workouts in the summer without acclimatising – this is a mistake,' says Michael Betts, personal trainer and director of TRAINFITNESS. 'Our bodies generally need one to two weeks to adapt to exercising in the heat.
'Older adults need extra time for acclimatisation because ageing affects your body 's ability to regulate temperature. Your sweat response becomes less efficient, and your cardiovascular system may not adapt as quickly to heat stress.
'Start with shorter sessions that are less intense and gradually build up your tolerance.'
Apply sunscreen
' Sunscreen with SPF30 or higher should be applied 30 minutes before going outside,' advises Betts. 'Reapply every two hours or more frequently if you're sweating heavily.
'Don't forget often-missed areas like the tops of your ears, feet and the back of your neck.'
Work out in the morning
'Early morning between 6am and 8am offers the coolest temperatures and lowest UV exposure,' says Betts. 'Your core body temperature is naturally lower when you wake up, giving you an advantage for temperature regulation.'
He also recommends avoid exercising between 10am and 4pm if possible, as this is when temperatures peak and the UV rays are at their strongest.
'This window is particularly dangerous for older adults whose bodies take longer to recover from heat stress,' explains Betts. 'If you must exercise during these hours, seek shade and reduce intensity significantly.'
Stay hydrated
'Exercising in the heat causes your body to sweat, which is a way of regulating your body temperature, helping your body to cool down, but without enough water your body could overheat or even experience heat stroke,' warns Sarah Campus, personal trainer and founder of LDN MUMS FITNESS.
'Staying hydrated supports mental sharpness, and supports body and muscular function, allowing for increased flexibility and mobility.
'Also, hydration is important for your heart as without enough water you could feel faint or dizzy.'
Be aware of signs of heat exhaustion and dehydration
'Dry mouth, dry lips, headache, dizziness, dark yellow urine, muscle cramps and a fast heartbeat are all warning signs to look out for,' says Campus.
Wear cool clothing
'Your skin's ability to regulate temperature decreases with age, making proper clothing choices even more critical,' explains Betts. 'Cotton holds sweat against your skin instead of wicking it away, which prevents your body from cooling effectively.
'Instead, opt for loose-fitting light coloured clothes which will reflect the heat and allow air to circulate around your body.
'Synthetic materials like polyester blends or merino wool work well for moisture management. These fabrics dry quickly and help sweat evaporate, which cools your skin. Some modern fabrics even have built-in UV protection.'
'Hats with wide brims will protect your face, ears and neck from the sun while giving a bit of shade, helping keep your head cool,' says Betts. 'Hats with mesh panels or ventilation holes will help prevent heat building up.
'A hat with a neck flap offers additional protection for this vulnerable area.'
Exercise in the shade
'Exercising in shaded areas or with frequent rest periods are smart choices,' says Betts. 'Circuit training where you move between shaded stations works well.
'Body weight exercises under trees or covered pavilions let you strength train without direct sun exposure.'
'Low to moderate intensity activities work better than high-intensity training in hot weather,' recommends Betts. ' Walking, gentle cycling, tai chi, and yoga generate less internal heat than running or intense interval training.
'These activities allow your body to maintain its cooling mechanisms more effectively.'
'Move into a cool shaded area to cool down and stretch,' advises Campus. 'Do some light walking and deep breathing as this helps bring your heart rate down gradually. You can also apply a cold compress to your wrists and back of the neck to cool you down quicker.'