'Sweat' doesn't mean 'workout.' Cooler temperatures can keep the perspiration down. But the heart rate can be just as high as a workout on an 80-degree day. Either way, learn about your body's cooling system, stay hydrated and enjoy a safe workout.

The saying goes, “Let’s exercise and work up a good sweat" like sweating is a sign that you’ve had a good, productive workout. But what if you exercise and you don’t really sweat during the workout? Was that workout not productive? Does it mean you did not workout long or hard enough?

The purpose of this article is to educate and enlighten you on the facts behind what is sweat, how do you know how much to drink to replenish your body and does it matter whether or not you “work up” a good sweat?

The body produces heat. The more activity, the greater the muscular contraction, the hotter the temperature, and the more humidity in the air, the more heat your body is producing.  Your body has several methods of keeping you cool. If it did not, you would overheat and collapse within 20 minutes.

The body has four ways in which it can cool itself; radiation, conduction, convection, and evaporation. The first, radiation is heat radiating out of the skin if the air around you is cooler than your body. The second, conduction is the transfer of heat, by direct contact for example, swimming in a pool of cold water where the water absorbs your body heat. The third is convection where moving air cools us down like when you stand in front of a fan or when the wind blows. Finally, there is evaporation where water from our blood absorbs the heat and rises to the surface of the skin through the sweat glands so it can evaporate creating a cooling effect.

In colder climates or indoors, your body will not need to sweat as much due to the body using radiation to keep cool. In hotter conditions, sweating is the primary method of keeping cool due to the air being hotter than your body but if there is humidity present, sweat cannot evaporate as well and that’s why you will see sweat dripping off you. Since in these conditions sweat doesn’t evaporate, radiation is also used by your body to keep cool.

The amount each person sweats in contingent upon many variables. Age, fitness level, gender, and environment contribute to how much you sweat. Women seem to sweat less and start to sweat at higher temperatures than men. The elderly tend to sweat less as they grow old which is why they cannot adapt to extreme heat as well as a younger person. This however may be due to their fitness level as studies have been done comparing older and younger individuals with similar fitness levels and they perspire equally.

Exercising in an air-conditioned room or outside during cool weather, you will not sweat as much because the cold air evaporates your sweat. It also sets your body up to use more of the radiation method meaning your body can deal with the heat created by exercise more easily. The amount of sweat you produce is not correlated to the number of calories being burned because the intensity and length of time of your exercise is what determines caloric burn, not how much you sweat. When you are exercising, you are sweating all the time you just can’t see it because it is always evaporating.

Here are some interesting facts about sweat you may or may not already know:

• Sweat is made up of primarily of water, potassium and salt. The ratio of those elements varies from person to person, and your body adjusts that ratio depending on the fluctuation of its levels of water, potassium and salt.

• Wearing plastic suits to sweat more in an effort to lose weight is a dangerous practice. These suits increase your body’s temperature and increase the amount of sweat your body produces but do not increase weight loss and can lead to dehydration as well as serious heat complications.

• The average person has 2.6 million sweat glands in their skin. The glands are distributed over the entire body with the exception of the lips, nipples and external genital organs.

• We have eccrine sweat glands all over our bodies, including the palms of our hands, the soles of our feet and our foreheads.

• Apocrine glands contain proteins and fatty acids, making their secretions thicker and giving them a milky or yellowish color. That's why underarm stains in clothing appear yellowish.

• Losing excessive amounts of sweat can quickly dehydrate you, leading to circulatory problems, kidney failure and heat stroke.

• Sweat is made from fluid in your blood, which means the more you sweat, the thicker your blood becomes and the harder your heart has to work to pump that blood.

• An hour or two before exerting yourself outdoors in the heat, drink 16 ounces of water or sports drink, then take in between 5 and 12 ounces every 15 to 20 minutes while working or exercising, says Runner's World magazine.

By Christina Leon, Staff Writer