Running in the heat - 7 ways to stay safe when running in the sun

running in the heat

The distressing footage of Callum Hawkins collapsing during the marathon in this year's Commonwealth Games is hard to forget. But heat-related issues and injuries don't just affect elites gunning for medals; all runners should be mindful when pushing the pace on a hot day. 

Here are a few tips to help keep you safe: 

1. Instead of avoiding heat during training, adapt to it 

A study in the European Journal of Sport Science found that even two, two-hour runs in hot temperatures stimulated marked improvements, such as decreases in core temperature and an increase in blood plasma, which helps maintain optimum temperature. 

Related: 8 tips for running a race in heat you haven't trained for 

2. Train to a target heart rate 

As you adjust to running in the heat, you'll be able to go faster at the same number of beats per minute. 

3. Drink to thirst 

In a 2016 study, athletes completed a 20km trail run either drinking a set amount to replace their expected sweat loss or simply drinking to taste - their finish times were identical. 

Related: 9 dehydration symptoms that aren't thirst

4. Don't forget salt 

Running on a hot day means more sweating, and this sodium needs to be replaced. Nutritionist Renee McGregor estimates that at a temperature of 20C, the average runner loses about 1,230mg of sodium per hour, which can lead to gastrointestinal distress, dizziness and heat stress. Top up your sodium stores with salt tabs, sports drinks and real food. 

5. Adjust your goals 

A study into the effects of heat on marathon running, published in the journal Medicine & Science in Sports & Exercise, found that sub-elites tended to run 20 minutes slower in temperatures between 21C and 26C. 

6. Add sunscreen 

Some runners claim that sunscreen clogs up sweat pores and makes you overheat, but a study commissioned by the US military found that using sunscreen did not adversely affect heat-regulation variables such as skin temperature. That said, not all sunscreen is created equal. Go for at least factor 30 and apply liberally (most of us use about half the required amount). Make sure it's broad spectrum, offering protection from UVA and UVB rays. We've summed up the best sunscreens for runners here. 

7. Head to the trail 

Roads retain heat and radiate it back onto your body, making your run hearder, so head to the grass and shade of some nearby trails. Carry water and a mobile phone with you.