You've probably seen how runners in the New York City marathon refresh themselves during the race. They grab a paper cup on the fly, gulp it down or splash it on their face, toss the crumpled cup away and keep running-all without breaking stride. A lot of people approach long-distance summer driving the same way, zooming into a rest stop to gas up, gulp a burger, and get back on the road.

But is that any way to take a vacation? No way. In fact, your well-being-not to mention the well-being of your car-may depend on when, where and how you take a break from a long drive. So when you set out on your summer marathon, follow these tips from automotive and safety experts:

Get Into Shape

You wouldn't dream of getting up off the couch and running a marathon tomorrow. Then what makes you think you can cover hundreds of miles behind the wheel with only the barest minimum of preparation? Before you leave, get your vehicle in peak working order. Check and fill all fluid reservoirs (including washer fluid), as well as the tires.

When you pack, take care to stay well within the vehicle's weight capacity-the total pounds of people and cargo that it can safely carry. You'll find the weight capacity on the tire inflation placard, which is usually on the driver's doorjamb. (It may also be on the edge of the driver's door, glovebox door or the fuel filler port door.) Overloading the vehicle strains the engine and transmission and makes even fully inflated tires run hotter, increasing the risk of a blowout.

If you're driving a sport-utility or recreational vehicle loaded near capacity, inspect the cooling system thoroughly. Look for soft, spongy hoses and worn or cracked belts.

"All cooling system components, including belts, hoses, water pumps and thermostat, should be checked by a specialist if you'll be using your vehicle for towing or off-roading," says Don Hart, president of the National Automotive Radiator Service Association. "Towing or driving in low gear can cause a vehicle's cooling system to work harder to dissipate additional heat generated by the engine."

Maintain your body, too. Rather than staying up late packing, get plenty of rest the night before your road trip.

Map Out a Strategy

Any marathoner will tell you that distance running requires a strategy. When will you set the pace? When will you conserve your energy? When will you begin your final kick? A plan of attack is important in long-distance driving, too, because your life depends on it.

"We recommend taking a break every two hours-every 100 miles or so," says Stephanie Faul of the AAA Foundation for Traffic Safety. Timing your breaks becomes crucial at night or between 2 and 4 p.m., when your body's circadian rhythm makes you sleepy. Statistics show dramatic spikes in drowsy-driving collisions during those hours.

If you're driving with family or friends, decide who will drive, who will nap in the car and when you'll switch. If you're driving alone, schedule a 20-minute mid-afternoon "power nap." (AAA TripTik routings, which show locations of gas stations, restaurants and rest areas with or without restrooms, really come in handy for scheduling.)

Take a Break

When you finally reach the exit, rest area or service plaza, make the gas pump your last stop. First, head for the restroom or restaurant, and grab a few paper napkins or paper towels on your way out. After letting the car sit for five or ten minutes (but before restarting it), pop the hood and check the oil, using the napkins to wipe the dipstick. The wait allows the oil to drain down and gives you a true reading.

Generally, highway driving consumes far more oil than ordinary city driving, so it's a good idea to check the oil at every fill-up during the road trip. But overfilling the oil becomes almost as bad as running low; too much oil creates foam in the crankcase, which doesn't lubricate as well. You want to get it just right.

While you're under the hood, check the other fluids, especially the windshield washer reservoir and coolant overflow tank. (Don't open the radiator cap! The system takes a long time to cool, and you risk getting sprayed by scalding coolant.) Forget the tires. Heat from all those highway miles will have inflated the inflation reading. You want to check the pressure tomorrow morning, when the tires are cool.

If you're driving alone, now is the time for a short siesta. "You should drink a caffeinated beverage before you nap or doze," advises Darrel Drobnich of the National Sleep Foundation. "It takes 15 to 30 minutes for the caffeine to get into your system, so you'll get the full benefit when you wake up."

Surprisingly, coffee may not be the best caffeinated beverage to choose. Recently, British researchers measured the caffeine content in coffee at rest stops along motorways. It varied wildly; taste, color and smell gave no indication of how much caffeine was contained in the brew. The roast, grind and brewing methods also affect the kick in your cup of joe.

Instead, many experts recommend a beverage with a known caffeine content, such as a soda or energy drink.

After taking a nap-and fueling up your body and your car-you're ready to put more miles behind you.