Dehydration is caused by an athlete not sufficiently replacing fluid losses during exercise which is caused by sweating in order to maintain a constant core temperature and the body not over heating through exercise. Therefore sweat rates are naturally higher when athletes are exercising at higher temperatures.
The main impairments are as follows, with the magnitude increasing as the level of dehydration increases:
- Increased heart rate
- Impaired heat regulation- leading to the risk of heat stroke
- Exercise feels harder than normal
- Reduced mental function
- Reduced skill level
- Stomach upset
To ensure that athletes maximise their rehydration, the most important thing is that drinks are palatable and are non-carbonated. The amount of carbohydrate and electrolytes will be linked to their palatability, the type of training and the environment the athlete is training in.