Some fitness classes promote “no sweat exercise” as a selling point while others want to convince participants that dripping with sweat is somehow magical.
However, the degree with which a person perspires has less to do with the efficacy of the exercise routine and more to do with the temperature of the environment and the body’s ability to cool itself. Sitting perfectly still in a sauna can produce buckets of sweat, whereas going for a run in a T-shirt in frigid temps might not result in any perspiration.
Sweating is the body’s cooling system and keeps us from becoming dangerously overheated. The fluid that exits the pores is mostly water with trace amounts of minerals. There is no fat loss from sweating. When fat is metabolized, it primarily leaves the body through respiration as carbon dioxide.
However, this doesn’t mean sitting around and doing heavy breathing is a fat-burning activity. The fat has to first be mobilized out of storage through the complex process of metabolism, which is greatly enhanced by physical activity.
Weight that is lost through heavy perspiration is water weight and will come back as soon as the fluids are replenished. Human beings are roughly 80% water and every cell needs water to function. It’s critical to replace the fluid lost through sweating to avoid dehydration — a potentially life threatening condition.
There is also a misconception around sweating as a way to release toxins from the body, but toxic substances are not released through perspiration. Toxins in the body are filtered through the kidneys and the liver and then excreted. However, drinking plenty of water (which we are prone to do when we sweat) can help improve the function of the kidneys.
The amount a person perspires depends on several factors, including gender. Exercise that puts a big metabolic demand on the body tends to cause more perspiration because it quickly raises the core body temperature. Someone who exercises frequently will probably perspire more quickly and produce more sweat than their more sedentary friends. Just as the cardiovascular system improves with exercise, so does the cooling system.
Partaking in strenuous exercise in hot temperatures can cause a person to lose excess minerals through sweat — including sodium. If sodium levels drop too low, a potentially life-threatening condition known as hypotremia (too much water in the cells) can occur. Electrolyte drinks that include sodium can be helpful for endurance athletes in hot weather as well as restricting outdoor training to the cooler, early morning hours.
With the hot days of summer still upon us, it’s more important than ever to stay hydrated. Children and the elderly tend to get dehydrated more quickly and need to pay special attention to getting enough fluids. Keep your water bottle handy and if you’re someone who tends to perspire a lot consider adding some electrolytes.