Sweat Rate Calculator & Health Guide

Sport is a sweaty business. But it’s difficult to make generalisations about how much people sweat. For example, some people start dripping with sweat as soon as they sit down in the sauna, while others only just begin beading up when they are about to leave.

In sport it is important to know your individual sweat rate. This helps you to determine your fluid requirements . Knowing how much water you need to take with you not only ensures you have a sufficient supply of liquid, but also means you won’t have to carry unnecessary extra weight.

Your sweat rate can vary

The sweat rate of a person does not remain constant. It varies depending on the intensity of the effort, and there is also an adaptation effect, for example, when the body spends an extended period of time in warmer or colder conditions than it is normally accustomed to. You will start to adapt after just 10 to 14 days’ residence in a different climate. But the actual temperature is not the only factor which affects your body, the heat index can be much more important. This value offsets the actual temperature against the humidity to give an approximation of the apparent temperature perception for the body.

On the other hand, in windy conditions the body cools down more quickly, because energy is removed by the wind. This effect is known as the wind chill effect. This also has an influence on the sweat rate. Don’t be fooled by the wind: Even if your clothes are staying dry, your body is still losing moisture. It’s just evaporating immediately in the wind. We are familiar with a similar effect in cycling.

Fit people sweat more!

It used to be a common knowledge, that those who sweated more, were less fit. Now we know: The exact opposite is the case! With progressive training, the body learns to use its temperature regulation more efficiently, and to get it going quickly. So those who train regularly improve not only their fitness, but also their own capacity for keeping cool.

The connection between sweat rate and hydration

Knowing your own sweat rate is important in sport, not least because it helps to guide your hydration requirements. Because: What goes out, must come back in again. If the body gets dehydrated, performance quickly drops – in extreme cases it can lead to delirium and even to loss of consciousness.

If you want sustained performance, you must have adequate hydration. It’s better to have frequent, smaller sips, since a sloshing belly full of water won’t help your performance either.

Mineral loss through sweating

Everyone knows: Sweat is salty. In fact we lose a large amount of salts and minerals when we sweat. The theory is that the saltiness of sweat improves the efficiency of the body’s cooling system. The substances lost from the body should be replaced by drinking. Isotonic drinks are better absorbed by the body and drinks containing minerals replenish the body’s supply of important minerals and salts.

Here’s a useful trick that will be easier on your budget than using sports drinks all the time: Dissolve between one quarter and one half of a teaspoon of cooking salt in a litre of water; this will replenish the body’s lost salt.

Drink more = sweat more?

If you drink more you don’t automatically sweat more! Thermoregulation is vitally important for the body, since the body’s temperature must be kept constant. This is because all of its vital functions must be well-regulated. If you drink more than you need, the unused liquid with be expelled as urine. But if you drink less, your performance will suffer.

Sweating to lose weight?

Don’t even think about it! The hydration of the human body is a finely tuned instrument, and your fitness depends upon it. In most cases, any weight loss through sweating is minimal and short lasting, since your body will just use thirst as a signal that moisture needs to be replenished.

If dehydration is maintained for a prolonged period of time, this will have a negative impact not only on performance, but also on vital organs like the liver and kidneys. These organs will no longer be able to remove toxic substances from the body and in the long run this can cause illness. Even people who have become accustomed to drinking very little in general will compromise their health over time. Headaches are often a sign of dehydration. Losing weight through sport is best achieved by systematically increasing your energy expenditure consistent with your calorie intake. Your energy expenditure during particular sports can be calculated with our calorie calculator (coming soon).

When is sweating unhealty?

Is sweating after sport unhealthy? Probably not. Sweating after exercise is a phenomenon that helps the still-elevated metabolism to return to normal after vigorous exertion. After exertion, it helps to give the body a reasonable time to relax, so that the core temperature can return to a normal level.

In addition to this, some people suffer from severe night sweats. A perfectly straightforward cause of this can be consuming food too close to bedtime. However, if it persists, it can also be an indicator of various different illnesses. If in doubt, it is best to consult your doctor. Some people find that their palms sweat excessively, which can be a major hindrance, especially during activities like climbing. In this case too, a doctor can help you to find the right treatment and investigate the root causes.

Conclusion

Your sweat rate helps you to determine your essential level of hydration. It can also be an indicator of a person’s fitness level. With increased training the body learns to use its temperature regulation more efficiently and to start using it sooner. This cooling effect helps to keep the body performing to a high level and is extremely good at adapting to different environments. When you’re training hard, the best thing to do is: Ensure an adequate fluid intake and, if necessary, a little salt.