Running in the heat

As the mercury rises, you’ll notice your rate of perceived exertion (RPE) increase when you run. In this article, we share tips on how to stay cool and cope with the heat. But before we do, it’s worth understanding why it’s harder to run in the hotter temperatures.

Aside from simply an increase in body temperature (just like when you have a fever), when your temperature rises, blood is diverted to the skin. The body does this to allow for cooling through sweating and then evaporation – this is your body trying to cool yourself. However, as blood is diverted from the skin, your muscles have a decreased supply, which means less oxygen transportation to the muscles which you use to run, thus increasing your RPE at various paces.

As a final straw, increased heat means a higher risk of dehydration which compounds the problem as your body finds it harder to cool itself, further limiting performance.

Adjust your pacing strategy
Simply put, slow down! Understand why you are finding it harder to hold your normal paces, accept it and make the necessary adjustments. Mindlessly pushing yourself in order to stick to normal paces will only mean you’re working too hard – you’ll either be training in the wrong zone, will become dehydrated or you’ll take longer to recover…or all three!

Don’t stress if you need to wind it down. Keep your RPE (and heart rate, if you track it) in the right spot and you’ll still be getting the physiological benefits even if you’re running slower.

Nail your fluid intake
As we mention above, adequate hydration is critical to letting the body perform its cooling duties as optimally as possible. If you neglect it, it won’t get the job done, and your RPE will continue to rise and dehydration will creep up.

We can’t give you an absolute amount of how much you need to drink – it varies for everyone – but a good way to figure out your sweat rate is to weigh yourself before and after a hot run and take into account how much fluid you consumed. For example, if you run for 60 minutes and lose 0.5kg, but drink 500ml, then your sweat rate is about 1,000ml per hour. You need to try to drink this much going forward.

Get your kit right
This one is probably rather obvious, but ensure you’re wearing lightweight, easy-wicking fabrics that help your body cool.

Electrolytes
Sodium is the predominant electrolyte here, but potassium and magnesium are also important. Electrolytes are crucial because they help your muscle cells retain the right amount of water. This balance is key, and if you drink too much water but do not get the electrolytes in, you could be in trouble.

Most sports drinks these days include more sodium, potassium and magnesium than they used to, just be sure to buy a brand which places emphasis on their inclusion.