physiotherapy sport

Why do I sweat when I exercise?

Is the key to getting fitter and stronger really ‘blood, sweat and tears’?

Not sure about blood and tears, but sweating is key to managing body temperature whilst exercising. Now that we’re leading into summer, the effect of exercising in hot conditions is even more significant.

When body temperature rises (in hot temperature conditions or during an intense workout), the body’s sweat glands kick into gear to keep our body temperature stable . The body has in inbuilt thermostat in the brain called the hypothalamus. When our core temperature increases, the hypothalamus triggers the sweat glands to release sweat- a mixture of water, sodium chloride, and other electrolytes .

Water is essential to maintain blood volume, regulate body temperature and allow muscle contractions to take place. During exercise, the main way the body maintains optimal body temperature is by sweating. When sweat leaves the skin’s pores, it evaporates into the air, taking some heat with it. This evaporation is what actually cools down the body. Sweat production, and therefore fluid loss, increases with a rise in ambient temperature and humidity, as well as with an increase in exercise intensity.

It’s not only body temperature that regulates sweating. During exercise, heart rate and blood pressure increase, which in turn cause the body to pump out more sweat.

Just because you sweat a lot, does not mean you’re less fit. Everybody regulates their body temperature differently- and some people may actually be more efficient at getting rid of heat by sweating more!

So, since sweating results in a loss of body fluid, it’s essential to drink lots of water before, during and after a workout to replace fluids lost in sweat. This action will reduce the risk of heat stress, maintain normal muscle function, and prevent performance decreases due to dehydration. In a lot of cases, during intense exercise, the rates of sweat loss are higher than the rate you can drink, which can result in a fluid deficit. Therefore it’s important to know your body, drink adequate amounts to reduce the fluid deficit and potential performance detriments associated with dehydration. However, it is also important to know that it is possible to over-drink during exercise, which can effect the body’s electrolyte balance. This highlights the importance of getting to know your sweat rate and knowing how much you should be drinking. See our sports dietitian Margaret Mielczarek for an individual fluid plan.

And remember- For a dream to become a reality, it takes SWEAT, determination and hard work!


Recent Posts