There are a lot of ways to prepare for running and racing in the heat. I won’t cover these here, but rather focus on what to do on race day itself. But please have in mind that the more acclimatised you are, the better you will perform. These are my key strategies for racing in hot conditions:
This is obvious, but still very important. Do all you can in order to keep your core temperature down. If possible, soak your self as often as you can in cold water. It is a good investment in time to soak yourself in a cold creek for a minute or two – you will race faster as soon as you core temperature decreases a bit.
Another way to stay cool is to use ice. This isn’t always doable, but if you have the chance; use ice! One way is to use an ice-bandana around your neck. The bandana can be made of just a square piece of cloth with ice cubes in it. Another possibility is to put ice cubes in your arm sleeves, under your hat or in your shorts/bra. Yes, I know that the latter sounds cheesy, but it does work.
Run faster at night
In long races, I would recommend to adjust your effort according to the temperature. I try to run a bit slower during the warmest hours of the day (between mid-day and 18:00) and then turn up the intensity at night time.
I always use a cap and sunglasses in hot and sunny conditions. The cap’s visor gives shade for my face, and the sunglasses at least gives my mind the impression that it is not that hot.
It is important to hydrate according to your effort level and the conditions. It is quite a bit of discussion in the ultra world regarding how to hydrate. Some say “listen to your body” and hydrate to thirst, and some use a more strict and regulated hydration regime. There are pros and cons with both regimes. I still prefer to listen to my body, give it fluids when I am thirsty, but not over hydrate. I am very aware of the risk of Hyponatremia, or low sodium concentration in the blood. Hyponatremia is dangerous and can happen when over hydrating and then flushing out too much sodium.
I would recommend to use light coloured clothes in hot conditions. Some prefer white shirts and/or caps, for me a yellow shirt works well.
Sondre at the Marathon des Sables
I have used these hints and tips in two of my really hot races, the Western States Endurance Run and the Marathon Des Sables. I had not any serious issues with the heat and performed well. Check out my video of the MDS to see how I managed the heat there. I wish you good luck in all your (hot) training and racing!