The Facts About Sweat

    It's cool to sweat -- literally. Sweating is your body's most effective way of cooling itself because when sweat evaporates from your skin, body heat is reduced.

    While sweating is important, if you don't replace the fluids you lose through sweat, it can lead to dehydration and heat illness. That's why fluid replacement before, during and after exercise and activity is so crucial.

    What Happens When We Sweat

    During exercise, the heat produced by working muscles exceeds the heat released by the body, and body temperature rises. The rise in body temperature causes an increase in sweating and blood flow to the skin. As a result heat is removed by the evaporation of sweat from the skin, radiated from the body to the cooler surroundings, and is lost by convection to moving air.

    Our bodies are approximately 55-65% fluid. When some of that fluid is lost through sweat, it affects our cardiovascular system and our ability to control temperature.

    Factors that Influence Sweat Rates

    • Environment - High temperatures cause you to sweat more quickly and to lose more fluids through sweat. Humidity also affects your ability to cool off. It's harder for sweat to evaporate in hot, humid weather than in hot, dry weather heat index chart.
    • Exercise intensity - As your body works harder, body temperature increases, which leads to greater sweat loss.
    • Clothing and equipment - Minimal, loose-fitting clothing helps promote heat loss. Heavy clothing and equipment (e.g., football uniform and helmet) doesn't allow heat to be released as easily and increases sweating.
    • Genetics - Heredity has some effect on your ability to sweat, but being in good physical condition is usually a more important factor.
    • Fitness and acclimatization - As you increase your fitness, you become a better "sweater." You sweat sooner and you sweat more. The body adapts to exercise in warmer temperatures by sweating more.

    Sweat Glands

    • The body has approximately 2 - 4 million sweat glands weighing a total of approximately 100 grams (about 3 ounces).
    • The most concentrated area of sweat glands is on the bottom of our feet while the least concentrated area of sweat glands is on our back.
    • Women have more sweat glands than men, but men's are more active.