Sweating vs Fat Loss Truth: Does sweating more during exercise burn more fat? Know the real truth of what the doctors told

It is a very common belief among fitness lovers who do gym, aerobics or running that the more you sweat during workout, the faster the fat will melt from the body. Due to this misunderstanding, many people exercise in the scorching heat by turning off the fan, wear sweat suits or take sauna bath for hours so that they can sweat as much as possible. People also become happy after seeing weight loss of 500 grams to 1 kg on the weighing machine immediately after exercise. However, according to medical science, sports nutrition and endocrinology, excessive sweating does not necessarily mean burning more fat. According to doctors, there is no direct relation between sweating and fat loss.

The real scientific reason for sweating: body’s cooling system

Sweating is only a ‘thermoregulation mechanism’ in the human body. When we do any heavy physical activity or workout, the body temperature starts increasing due to the activation of internal muscles.

• The hypothalamus part of the brain activates about 20 to 40 lakh ‘Eccrine Sweat Glands’ present in the skin to maintain the body temperature normal (about 37°C).

• These glands release water, sodium and trace minerals from the body to the skin surface.

• When this sweat evaporates into the air, the body gets coolness. This means that sweating is just a natural process of keeping the body cool and not a measure of fat burning.

What exactly is the weight loss immediately after workout?

When you see less weight on the weighing scale right after a workout, it is not ‘fat loss’ but only ‘water weight loss’. As soon as you drink two-three glasses of water after exercise or have a meal, the body absorbs that water again and the weight comes back to its previous state. Even if a person exercises in the appropriate heart rate zone in an air-conditioned (AC) room without sweating, he still burns the same number of calories and fat.

How is fat actually burned and eliminated from the body?

From a biochemical point of view, when we are in calorie deficit and exercise, the fat stored in the body (triglycerides) gets broken down and converted into energy. In this chemical process, the breakdown of fat produces carbon dioxide ($CO_2$) and water ($H_2O$).

• According to a study published in the British Medical Journal (BMJ), approximately 84 percent comes out of the lungs through our breath (carbon dioxide).

• The remaining 16 percent is excreted through urine, sweat and other bodily fluids. So fat melting has to do with breathing rate and metabolism, not just sweating.

Why do some people sweat more and some less?

The amount of sweating varies from person to person, depending on several biological factors:

• Genetics and Number of Sweat Glands: Some people are born with overactive sweat glands.

• Weather and Humidity: In humid weather, sweat does not dry easily, which makes it appear that you are sweating too much.

• Body Weight: People with heavier bodies have to use more energy to keep themselves cool, which causes them to sweat more.

• Fitness Level: Fit athletes become so efficient at controlling body temperature that their cooling system quickly begins to produce sweat.

Serious dangers of forced sweating

• Severe dehydration: Due to severe lack of water and electrolytes in the body, there is a risk of dizziness, muscle cramps and fainting.

• Heat Stroke: If the temperature rises too high and sweat does not dry, heat exhaustion or heat stroke can occur, which can prove fatal.

• Pressure on kidney: Not drinking enough water after excessive sweating puts additional stress on the kidneys.