If your job keeps you on the road, you know how challenging it can be to stay fit and trim. After sitting for hours at a time in cars, planes or trains and subsisting on the high-calorie meals served in restaurants, you probably aren't surprised when your waistband starts to feel tight. You can prevent that from happening with a little dedication and some advanced planning.

Before your trip, prepare yourself mentally. Keeping up with your exercise program is important, so make a commitment to follow through with it. Remember to bring your athletic shoes, exercise clothing and any equipment you can conveniently take with you. Print maps from online sites for parks, malls or exercise trails near your lodging.

Lightweight, easily transportable gear that might come in handy includes:

• Jump-rope. Incorporate rope skipping into your calisthenics circuit. Try it in your hotel fitness room, the outdoor pool area, a local park or a rest stop.
• Swimsuit. Doing laps in the hotel pool is a great low-impact option.
• Personal radio or tape player. A little music could make exercise more enjoyable and keep you going. But keep the music in your room if you're biking or rollerblading outside. You need to be able to hear what's going on around you, such as traffic or children playing nearby.
• Resistance bands and tubing. Available at most fitness shops, resistance bands and tubing are useful tools for strength training.

Wear your walking shoes when traveling by plane — your fitness plan begins the instant you enter the airport. Since airlines ask that you arrive, in general, at least an hour and a half before your flight, take advantage of all the extra time you have. Either check your luggage early or place your carry-on luggage in a locker and walk briskly through the terminal, pumping your arms to increase your heart rate.

If you're taking the train, you can get some exercise by taking occasional trips through the cars or walking outside when the vehicle stops to let passengers on and off. When traveling by car, you have the advantage of stopping every hour to exercise. Try some stretches or fast-paced walking around your car.

When you arrive at your destination, visit the fitness facilities at your hotel. If there aren't any, ask the concierge or person at the front desk about nearby health clubs that offer day passes. Also ask about jogging and walking trails or malls where you can walk that close late or open early.

Other options abound:

• Walk or jog around the hotel perimeter or at a local park during daylight hours.
• Do jumping jacks and march in place in your room.
• Follow an exercise video you've brought from home. Call ahead to find out if your room will have a VCR.
• Find a TV channel that airs an aerobics program.

Complement your aerobic workout with some strength training. Using your own body as weight is most convenient. The following exercises are easy to do in your hotel room.

• Sit-ups or crunches for your abdominal muscles
• Push-ups for your arms, chest and shoulders
• Minisquats for your thighs
• Calf rises for the calf muscles in the back of your lower legs

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When you've finished your workout, don't forget to stretch.

Try to maintain your usual exercise routine. If you're used to early morning, noon or evening workouts, try to get your exercise at those same times when you travel. It helps your body adjust to a new diet, stress and time changes.

While exercise is important, don't be afraid to take time to rest. Jet lag and extreme schedule changes can take their toll on your body. If you've been through multiple time-zone changes or if your flight has left you exhausted, take it easy.

Taking care of your body and giving it the exercise it needs is energizing, though, and is just what you need to get down to business.