Evolution has meant that humans are well suited to endurance running. However, extreme temperatures, dehydration and humidity can still wreak havoc on the efficiency of our bodies.

But don’t worry! If you have a race coming up and it’s going to be hot, read our survival guide for running in the heat and humidity…


Stay hydrated

When humidity levels are between 60 and 90%, your heart rate can increase up to 10 beats per minute. This means an 8-minute pace might feel like a 6-minute one because the heart is pumping harder and faster.


Drink plenty of fluid, not only before (including the previous night and ½ litre of water at least 2 hours earlier) and after your race, but throughout the entire day.


For any race over 45 minutes, start your hydration early on; ideally, consume a sports drink every 20 minutes to help maintain electrolyte levels and refuel your muscles. Even if you don’t feel thirsty, drink at least ½ litre of fluid per hour.



Racing in extreme heat will also impact your nutrition. The hotter it gets, the harder it is to break down solid foods of any kind, so try to get most of your calories in liquid form.


Stay away from alcohol and caffeine

Avoid alcohol or caffeine drinks before and during a race as they increase urine output and leave you even more dehydrated.



While elite athletes use elaborate gear such as cooling vests, try something as simple as eating a very cold/frozen energy drink before your race. This helps cool your internal body temperature and delays its inevitable rise as long as possible.


Dress appropriately

Technical clothing enables sweat to pass through and evaporate, keeping your core temperature lower. For sun protection, a better option is a cap and a lightweight, long-sleeve running top. Stick to white or light-coloured clothing which reflects rather than absorbs heat. Remember not to wear a tight-fitting hat or one made of thick material, as it’s important to allow heat loss through your head.


Start slowly

Warm up in the shade with a shorter than normal warm-up time, so you do not raise your core temperature too much. It is also beneficial to start your run more slowly than usual. If you routinely run at 8-minute mile pace, try to run 10-minute miles so it takes longer for your body to overheat.


It’s all in your head

Although running in the heat has many physical ramifications, it is also essential to have a suitable mental approach. Possessing realistic expectations at the outset will undoubtedly contribute to a more successful race. We recommend lowering your time-based goals to reflect the conditions of the day and pacing yourself appropriately. You may be surprised by your performance!