If you find it difficult to stick with a fitness program, join the club. Roughly 50 percent of all healthy adults who begin a new exercise plan drop out within the first six months. Even more surprising are reports from the National Center for Health Statistics showing that only 32 percent of adults in this country engaged in regular leisure-time physical activity of any kind in 2001. That means most Americans aren't even getting the minimum amount of recommended physical activity, which, according to the American College of Sports Medicine, is 20 to 60 minutes three to five times per week. These humbling statistics are a reminder of how important it is to be intentional about our fitness goals. Now that it's the new year, perhaps you want to make a new start. Here's how you can ensure you'll be among the 50 percent who stay true to their fitness plans.

Set Realistic Goals

Experts recommend having a clearly defined fitness objective—;one that can actually be achieved. "People usually start an exercise program with the idea that they're going to change their lives," says Jon Schriner, DO, a sports psychologist and medical director of the Michigan Center for Athletic Medicine in Flint. "But they usually end up going too far, too fast, too soon." Being over-ambitious can cause burnout and hinder your ability to achieve your long-term fitness objectives.

Schriner suggests that instead of setting out to tackle hard-to-reach goals, focus on smaller, manageable ones that are relatively easy to accomplish. "Any reasonably healthy person can train to run a marathon," he says, "but it takes baby steps to get there." So if you want to lose 50 pounds, aim instead to shed two pounds each week. Each time you reach this goal, you'll be inspired to keep losing. If your dream is to run a marathon, enter a few shorter races first and be sure to cross the finish line. When you do, you'll be motivated to enter a longer race. By setting yourself up for success, rather than failure, you're more likely to stay motivated for the long haul.

Do Your Homework

One surprising reason why people give up on their exercise program, says Schriner, is injury. New athletes often don't spend adequate time gaining the information they need to pursue a particular sport or activity. "People decide they're going to get in shape, so they buy running shoes and start running down the street," says Schriner, who cites running as an example because it's cheap and perceived by beginners as not requiring an abundance of technical know-how. But you really should know a few things about running before hitting the pavement. For example, what are the proper running shoes for your feet, how far should you push yourself when you're just beginning, and how can you best avoid leg, knee, and ankle injuries?

To keep yourself injury-free, Schriner suggests that you build a knowledge base by speaking with a fitness professional, reading a book, or watching an informational videotape. Not only will you be more likely to avoid injury, you'll also immerse yourself in a sport—;be it tennis, yoga, or mountain biking—;that keeps you interested and on the go.

If you're not working with a personal trainer, it's especially important to research what type of exercise will best help you achieve your goals. For example, if you've been trying to lose unwanted pounds but can't seem to burn them off on the treadmill, you may want to consider weights. Resistance training is especially important for those trying to lose weight because it helps burn fat and build muscle mass. And increased muscle mass speeds up your resting metabolic rate, so you continue to burn extra calories even after you've left the gym.

Make It Fun

One not-so-shocking reason people lose interest in their exercise program is plain old boredom. That's why it's crucial to make working out a source of fun, rather than another chore that's been added to your to-do list. "Ultimately it's the responsibility of the client to figure out what's fun for her," says Kurt Murray, director of continuing education and TeleFitness services for the Aerobics and Fitness Association of America. "Motivation really does come from within." So spend some time determining what activities you really enjoy. Do you love being outdoors and hate being cooped up inside a gym? Look around for nearby parks and trails where you can go for walks on your way to or from work. Did you enjoy team sports in high school or college? Find an adult soccer or basketball league looking for new talent. Or maybe you simply need companionship to enjoy yourself. A fun group-exercise class at a local gym can be a great way to stay motivated.

One gym pushing the envelope in terms of fun is Crunch, with locations throughout the country, including New York, Los Angeles, and Chicago. In addition to the standard step and indoor-cycling classes, this fitness center now offers cardio striptease classes (yes, we said striptease). Participants shed more than pounds while learning the art of lap dancing, gyrating, and the use of props. Hey, whatever makes you sweat, right? Also on the schedule at Crunch: cycle karaoke, in which participants belt out their favorite tunes while riding stationary bikes, and circus sports, in which attendees take turns at stations such as tumbling, juggling, and even the trapeze. Although you may not be able to make it to Crunch, the idea that exercise can fit into many formats and be fun—;even a little racy—;is worth noting.

Get An Exercise Buddy

Exercise gurus can't stress it enough: Your chances of sticking to a fitness program increase if you find yourself a workout partner. "Get a friend with similar intentions and interests and set up a behavioral contract," advises Tom Collingwood, PhD, an exercise psychologist in Richardson, Texas. "Your contract could read, 'You will call me every day at 5 o'clock to remind me to meet you at the gym to play racquetball,'" he says. "After a month, if you stick to the deal, you're rewarded with a nice dinner out. If you don't, you're punished by having to do all your friend's dishes."

If a contract seems a little too formal, simply make an agreement that you'll call and meet your friend when it's time to work out. Be careful, though, when choosing your buddy, warns Kurtis Shultz, a Baltimore-based strength and conditioning coach. He suggests finding a partner at the gym, rather than talking your best friend into joining you on your fitness quest. "Find people interested in the same fitness activities and with the same goals," he says, "because a best friend may end up talking you into bagging the workout and grabbing a bite to eat instead."

If you can't find an exercise buddy, try keeping an exercise log. Begin by formulating your long- and short-term intentions and then record the activity you perform each day (along with duration and intensity, if you wish). The act of putting your goals in writing—;behavioral contracting, as Collingwood calls it—;helps you stick with the program once you maneuver the initial hurdle of starting one. Plus, it offers a tangible reminder of why you began your fitness routine in the first place.

Send Yourself To Camp

Finally, for those would-be coach potatoes who need the ultimate in imposed motivation, there's exercise boot camp. Offering a no-frills, machine-free, back-to-basics approach to fitness, boot camps use tried-and-true exercises to get recruits in shape: jumping jacks, push-ups, sprints, sit-ups, and all those other grueling calisthenics. Shultz, who leads four-week sessions during which recruits report in the early morning hours to participate in military-type exercises, says that boot-camp classes have gained popularity in recent years. (For details on boot camps, contact a local health club, which may offer boot-club classes or know of area programs.) "I've found that this type of environment is a great motivator, especially for those people just getting started in exercise and fitness," explains Shultz. "The people who are already in great shape really inspire the ones who are not." Usually taught outdoors, classes foster a feeling of camaraderie and encouragement, which helps those who are struggling make it to the end of the session. And after all, with a tough drill sergeant screaming at you to keep moving, who wouldn't be motivated?

Kelli Rosen is a certified personal trainer and Spinning instructor.