Athletes and workers in hot environments can lose 1 – 2L of fluid per hour through sweating dependent on factors such as:
- Type of exercise or work
- Exercise intensity
- Body type and size
- Female vs male
- Level of fitness
- Ambient temperature
Workers in prolonged hot conditions can lose 12L per day and thus it is vital to hydrate when carrying out exertion under hot conditions. The types of jobs where this could be relevant include: miners, farmers, rangers, surf lifesavers, roofing contractors, construction site workers; even racing car drivers; in fact anyone working outside in hot dry or humid conditions.
Our work has shown that sweat not only contains electrolytes but also large amounts of amino acids, the building blocks for our proteins, which also require replenishment. These salts and amino acids represent vital nutrients which the body requires to sustain good condition and performance capacity.
We now know also that the concentrations of amino acids in sweat are generally much higher in females than males under sedentary conditions with minimal exercise. Once the exercise increases to a level where 2L of sweat are excreted, the losses of amino acids escalate and are far more dramatic for females than males. This means that females may be significantly more susceptible to losses of amino acids during exercise and prolonged work in hot conditions.