If the engine in your race car gets too hot, it shuts down. Your body is no different. If you get too hot, you're going to shut down; that's something you don't want, especially if you're taking the white flag en route to your first feature win.

"In closed-car environments, the risk of heat stroke and heat exhaustion is real," says Kyle Keitzman of Bell Racing. But just what exactly is heat stroke, and why should a racer care about it?

Heat stroke and its two less severe cousins, heat exhaustion and heat cramps, are caused when the body cannot lose or dissipate heat. They are serious medical conditions and can even be fatal if not properly and promptly treated. Symptoms of heat stroke can sometimes mimic those of heart attack, and in certain cases, a person experiences symptoms of heat exhaustion before progressing to heat stroke. The symptoms of heat exhaustion may include fatigue, weakness, dizziness, headaches, muscle cramps, nausea, and vomiting-none of which you want to experience while in a race car.

To understand how to combat heat-related problems, we have to understand how our bodies work. During normal activity, the human body generates up to 50 degrees of added/excess heat in 24 hours. That is heat that your body must get rid of if it is going to maintain its internal core temperature of 98.6 degrees. When you strap into your race car on a hot summer night, your body is going to generate excess heat that it must dissipate.

There are four ways that it can accomplish this, and radiation is the most effective. Your body will radiate heat when the air temperature is lower than your body temperature. Next is evaporation, which is the release of perspiration through the sweat glands on the skin's surface-still very effective at keeping us cool. Convection is heat loss to air/water vapor, which must be lower than your skin temperature. Finally, there is the least effective way to cool your body: conduction, or the transfer of heat from warmer to cooler objects by direct contact. Ironic when you think about that, isn't it? What's the first thing we do when our bodies are overheated? Douse ourselves with water and a cold cloth. Yet that is the least effective way to get cool.

Now, when the temperature around you is over 95 degrees, radiation, convection, and conduction stop working, leaving only evaporation as the way to cool your body. "Big deal," you say, "we all sweat in the race car." Consider this: NASA did a performance study on how external temperatures affect the number of mistakes a person makes when performing a specific task. They found out that over the course of one hour, the average person made five mistakes when the temperature was 80 degrees. At 90 degrees, they made only nine mistakes during a 60-minute span. But when the temperature reached 95 degrees, the number of mistakes spiked to 60 in one hour. That's one goof every minute. Why? Because evaporation cannot handle the task of cooling the body all by itself. This is especially significant in a race car because firesuits do not let your body maximize evaporation.

Keep A Cool Head
"You can increase your performance by staying cool," says Jill Swanson, owner of Fresh Air Systems Technology (F.A.S.T.), the Illinois manufacturer of driver cooling products. "Keeping your body in better shape translates to keeping your mind in better shape. That means you can race longer, race harder, and think clearer."

Ultimately, making better decisions on the track can yield that prized trophy at the end of the race. But don't worry; you don't have to drop $3,000 on some fancy Nextel Cup cooling system to keep yourself in race-winning form.

In order to maintain optimum performance, you need to keep your body's core temperature at about 98.6 degrees F. Swanson says one of your goals should be to cool your chest area. While you can wear special shirts under your uniform to accomplish this, the first order of business is to make sure your lungs are getting cool, clean air. This fresh air is the beginning of keeping your core cool. But getting that fresh air to our lungs is a little complicated. Unlike Derek Jeter, Shaquille O'Neal, or other athletes, we race car drivers have a little something we call a helmet in our way.

Those of us who were Boy Scouts learned that one of the primary areas where heat escapes your body is through your head. As racers, we cram our noggins into foam-insulated, composite-wrapped chambers each time we strap into the car, and they can get hot. Helmet manufacturers have gone to great lengths to solve that problem by designing systems that maximize airflow.

"Our goal [in helmet design] is to return the body to a more natural form of cooling," says Bell's Keitzman. That means maximizing the airflow. When you sweat, moisture builds up. If that moisture can't evaporate, first comes heat cramps, then heat exhaustion, and finally, heat stroke. Keeping your body cool is all about helping that moisture evaporate through good airflow. Since air has a hard time flowing through a firesuit, the helmet becomes exceptionally critical in speeding evaporation.

Most racing helmets from reputable manufacturers usually have some type of ventilation system built in. These vents are actually channels that funnel in air from the front of the helmet up onto your face. Some helmet designs have outlets on the back that allow the air coming in from the front somewhere to escape.

Vented helmets rely on the air coming into the cockpit to keep you cool. A step up from the traditional vented helmet is a forced-air-style helmet. These helmets are designed to circulate fresh air from outside the car directly into the helmet.

There are essentially two different styles of vented helmets. One has a side-entry pipe, where the fresh air is vented across your chin and up around your face, and the other features a pipe on the top that funnels into channels or a bladder that dissipates the air around your head.

Side-entry-pipe helmets came first, but the top-entry ones are gaining popularity. Locating the pipe on the top of the helmet instead of the side allows for increased driver head movement because the pipe does not interfere with the protective head surround of the latest safety seats.