Training and Competitions in hot environments offer an additional challenge to athletes as heat dissipation becomes a limiting factor for performance.
During exercise in mild or cold climates, heat is mostly released from the skin to the environment through convection, whereas evaporative heat loss becomes the main method for heat dissipation when the surrounding temperature increases.
Hyperthermia can in itself inhibit performance, but particularly when combined with dehydration, can weaken the ability to maintain power output.
Training in the heat is an essential component in preparation for competitions in hot environments, but athletes should also consider performing heat acclimatization training as an addition to their normal training.
Here is a rough guide to acclimatization training -
1. Acclimatization can be accomplished in 7 to 10 days in non-acclimatized athletes with 1 hour a day of moderate intensity exercise in superimposed heat conditions (e.g. Sauna).
2. Heart rate can be used as guidance. At the start of the training session, heart rate can be used as a sign of the exercise intensity.
Since heart rate increases in correlation with hyperthermia, it will increase significantly during the heat training sessions.
This can be a good sign of a substantial increase in core temperature and therefore sufficient heat stress, on the condition that the exercise intensity remains unaltered.
3. Begin with an exercise intensity that after 5 minutes of exercise evokes approximately 60% of maximal heart rate and is perceived as fairly easy (3-4 out of 10).
During the initial acclimatization session maintain this intensity until the heart rate is within 10-15 beats of maximum and perceived as hard (8-9 out of 10).
Providing the environmental heat stress is high enough this should take 40 to 60 minutes.
4. During the following sessions, heart rate and perceived exertion should increase at slower rates (if the intensity remains unchanged), and the training sessions may be progressively extended or the athlete may perform the training with a slightly higher intensity.
