Racing and training in hot weather

Anna Ceruti
Jul 10, 2023
2 min read

Heat Acclimatization Tips

It's summer in the Northern Hemisphere, and it has been a hot one at that!

How do we maintain our training and racing schedule with these hard-to-manage temperatures?

Besides the obvious "go out for your session as early as you can," that might not always be agreeable with our life schedule. On top of it, it wouldn't provide any advantage if our coming-up race is in the heat.

So, what to do then?

Heat Acclimatization is the key!

Heat acclimatization is the heat tolerance that comes from gradually increasing the intensity or duration of work performed in a hot setting.

It takes the average person between nine and 14 exposures to become acclimatized, and the fitter you are, the shorter that time is.

What happens during heat acclimatization?

Several things happen during the acclimatization process that improve people’s ability to tolerate heat:

Blood volume expands. This allows the heart not to work as hard, thus reducing cardiovascular strain.
Improved sweating. Higher volume; earlier onset; decreased salt loss; sweating happens more on the limbs.
Improved skin blood flow
Lowered body temperatures
Improved fluid balance
Enhanced cellular protection.

Tips for acclimatization

You should build to match the volume and intensity you want to perform on race day: training at an easy effort in the heat will not prepare you to perform at a higher intensity later on.

The best way to acclimatize yourself to the heat is to gradually increase the workload performed in a hot setting over 1–2 weeks.

Be mindful to cool off and fully hydrate between workouts, always!

Tips for heat acclimatization in a nutshell:

Increase the volume and intensity of the workload in a hot setting gradually over 1-2 weeks.
The best results are obtained with at least 1-2 hours of heat exposure per day, which can be broken down into two 1-hour sessions.
More strenuous or longer efforts require more strenuous and longer acclimatization as the body adapts to the volume and intensity we are training it for. So, make a build-up acclimatization plan tailored to the demands of your upcoming event.
Stay Hydrated! Not only will dehydration reduce the benefits of your training. Acclimatization means higher hydration demands because the sweat rate increases.
Nourish your body! Food helps replenish lost electrolytes, especially during the first few days of acclimatization. So make a point to bring nutritious snacks before, during, and after your training sessions to maximize your results.
The fitter you are, the easier acclimatization becomes. This means that all the work that you put in before the heat acclimatization will play in your favor!

How long before we lose heat acclimatization benefits?

About 1 week away from the heat is enough to start losing the acclimatization effect. Within 1 month, we are back to baseline.

The good news is that a couple of days of training in cooler conditions or air conditioning breaks will not hurt your training acclimatization.

The long story short is:

Yes! We can get better at training and racing in the heat.

As always, we need to be specific with our training and keep in mind that hydration and nutrition play a fundamental role in general performance and heat acclimatization, too!