As the coach of Mieke Gorissen, I experienced two major championships in 2022: the Worlds in Eugene and the Europeans in Munich. Both marathons where heat played a role. How did we deal with it, and what can you learn from it?

Optimal Timing for Running in Hot Weather

The World Championships in Eugene started at 6:15 AM to avoid the worst heat. The organization wanted to stay ahead of the heat, and that kinda worked out well. However, I saw many participants struggling with the temperature towards the end.

Racing in ‘extreme’ conditions requires self-knowledge and realism, which doesn’t always work under competitive circumstances. To perform as an elite runner, that early start time is far from ideal since you need to have breakfast around 3 AM.
For us amateurs, nutrition isn’t that big of an issue for low-intensity workouts in the heat. If you set the alarm early for an endurance run , it can be done on an empty stomach (although I'm not a fan!). Take a gel just before heading off and you'll be fine, as long as you have a decent breakfast afterwards.

High intensity runs and an empty stomach do not go together. Adjust your training schedule if necessary - switch your sessions to skip the hottest days or wait for the evening for strenuous workouts.

In Munich, the marathons started at 10:30 AM (women) and 11:30 AM (men). Not an ideal starting hour. Temperatures rose well beyond 20°C during the race. If you can’t avoid training during the warmest hours, keep the following advice in mind.

Choosing the Right Course for Hot Weather Running

Urban residents know the "heat island" effect well. Avoid tracks or loops around the city ring for intervals or long runs. Seek parks and forests where nature provides a kind of natural air conditioning. You'll notice: running on the street vs. in the forest shows a significant temperature difference!

Hydration Tips for Running in the Heath

Drinking is important, but what you drink is equally important. If you sweat a lot and have a high thirst, don't just drink water but also replenish your salts. Only drinking water can disturb the electrolyte balance and doesn’t prevent heatstroke. Drink when you're thirsty and consider oral rehydration solutions (ORS) to maintain electrolyte balance.

Effective Cooling Strategies for Hot Weather Running

In Munich, we provided every Belgian marathon runner with a bag of ice. These were long washcloths or cotton bags filled 4/5th with ice. We "activated" the ice bag by pouring some water over it to enhance the cooling effect. Most runners placed these in their necks or under their caps. Pouring water over yourself can also help cool you down. Cooling strategies are important and easy to apply. Keeping your body temperature low improves performance.
Before you go out for a run, it even helps to dip your wrists in cold water. Wearing a cooling vest before your training session may be a bit 'too pro', but effective nonetheless!

Also: dress wisely! Singlet and split shorts. The less fabric there is, the better!

Acclimatization Techniques for Heath Adaptation

Give your body time to adjust to the conditions, heat acclimatization is a thing. Don’t stop running during those hotter days or don't always opt for the coolest times of the day. Everyone reacts differently to heat, but everyone can adapt to it. For example, my Garmin provides insights based on training sessions and intensities in temperatures of 22°C or more, showing how well I am acclimated. In order to adapt, you have to expose yourself to these temperatures.

Personally, I hate the heat but understand that it will occur more frequently in the future. So, I kept training, first during cooler hours and then during warmer hours. Now I handle the heat much better than before. I lose less fluid, can maintain higher paces, and my heart rate is lower as a result.