Training and racing in the heat
How heat affects performance, how to acclimatise and what to adjust in pace, hydration and timing.
In the heat, your body has to split blood flow between your muscles and your skin to cool down. As a result the same pace costs more and heart rate rises even if you don't speed up.
Adjust your expectations
In high temperatures, your usual pace isn't a realistic target. Go by heart rate or feel and accept running slower. In a race, starting conservatively is the best strategy.
Acclimatisation
The body adapts to heat in about 10-14 days of exposure: you sweat sooner, lose less salt and heart rate rises less. If you're racing somewhere hot, doing some sessions in those conditions in the weeks before helps a lot.
Hydration
- Drink regularly, without waiting until you're very thirsty.
- In long efforts, add electrolytes to your drink.
- Weigh yourself before and after a long session to learn how much you sweat.
Practical tips
- Train early in the morning or in the evening.
- Light-coloured clothing and a cap.
- Pour water over your head and neck at aid stations.
Dizziness, chills or confusion are signs to stop immediately.