The idea is to focus on the enjoyment of being active, the feelings of competence and the social interaction that come from the experience. A study in the "International Journal of Sports Psychology" showed that a group who participated in aerobic exercise to improve their physical appearance didn't stick with it nearly as long as a group who did martial arts because they enjoyed it.

Here are just a few ideas to get yourself moving while having fun:

PARKS AND RECREATION AREAS

Going to a park ensures that you do something physical, and whether you're on a nature walk with the kids or paddling a canoe across a lake, you won't feel for a moment that you're getting additional physical activity. Parks make the perfect mini-vacation.

With everything from monuments, hiking, canoeing, kayaking and water-skiing, to rock climbing, wildlife observation and caving, all you need is a place to get started. Begin by checking out the government's Web site at www.recreation.gov. It's a one-stop shop to learn what activities are available close to your home.

Charlie Grymes, project manager for Recreation.gov, adds that there are 16,741 miles of trails in parks that range in size from one-fifth of an acre to 13.2 million acres. Recreation.com also has links to state tourism sites that offer even more activities. With all this information you can be busy for the rest of the year.

Another site to check out if you want to go hiking is www.trails.com, which lists more than 35,000 trails.

THE WATER

A day at the beach can provide a lot more exercise than you'd think, as long as you don't spend the whole time on your towel. There's beach volleyball, Frisbee, Kadima (beach paddle tennis), touch football, swimming, even a nice long stroll. They all burn calories — not to mention the total body workout you get when you battle the waves. In just a half-hour, here's how many calories you'd burn:

• Beach volleyball: 280 calories

• Frisbee: 105 calories

• Bodysurfing: 106 calories

• Touch football: 280 calories

• Swimming: 300 calories

• Kayaking: 176 calories

• Canoeing: 110 calories

ZOOS AND AQUARIUMS

The zoo is an excellent place to get in some walking in addition to some family time and fun. With almost 200 zoos nationwide, chances are you're only a short trip away from a day with the animals. You can easily spend a few hours visiting various habitats, and a single hour of leisurely walking burns almost 200 calories. And you'll burn even more if you're pushing a stroller. Just make sure to steer clear of any diet disasters your local zoo may be frying up. Pack your own lunch and snacks to ward off hunger.

There is less walking at an aquarium, but you can still manage to get in a good 20 to 30 minutes in a visit. Maybe it's worth buying a membership if you live nearby.

BOTANICAL GARDENS

If you're not into animals, consider a trip to your local botanical gardens. It's another great way to get out in the sun and get walking — and a bit more romantic and relaxed than the zoo. Take a walking tour and burn even more calories.

SIGHTSEEING

Sightseeing is another excellent way to sneak in exercise under the guise of entertainment and education. Learn about your city or someplace new while you shed extra pounds. Consider investing in a pedometer, and watch the steps add up. Sightseeing is very distracting. Before you know it, you'll have walked a few miles.

• Walking tours: There are probably organized walking tours available.

• College or university campuses: There are thousands of colleges and universities in the United States. Universities spend lots of money to create beautiful campuses, which are great for walking and sightseeing. If you want, you could probably even take one of the tours most colleges and universities offer for prospective students. These are much like city walking tours — full of fun facts, anecdotes and historical details. Call ahead to find out when tours are running, and tag along with the pre-freshmen.

• Company or plant tour: Many companies offer tours of their facilities that are a great way to get exercise and see something interesting.

SHOPPING

There are more than a thousand shopping malls in the United States. Walk the entire mall for a good 30 minutes at moderate speed. The level flooring (fewer injuries) and air conditioning are excellent motivators for using the mall as a walking spot. And you'll also have the benefit of "people watching" (which makes the time fly) as well as fantasizing about all the great clothes you'll be able to buy — in a smaller size — when you've reached your weight-loss goal. Check to see if your neighborhood shopping mall has any walking programs available. Just think twice before you chow down at the food court.

MUSEUMS, LIBRARIES AND GALLERIES

Art museums also provide comfortable spaces for walking as leisurely as you'd like with plenty of visual stimulation. If you're up for a full day of art, you can continue to explore on your own. Organized tours are often free or inexpensive and generally run 30 to 60 minutes.

If you're not an art nut, don't shy away from the museum walk just yet. You may be surprised to find how many interesting places are tucked away out there. There are history museums and libraries, all of which offer a place for you to walk. And if those don't sound appealing, find ones that do.