Fun Ways to Burn Calories Outside the Gym

Try Hiking Yoga (400–610 calories)

Sneaker-clad certified yogis will guide you briskly through parks and along trails, pausing to lead you through basic yoga poses. In a win-win-win workout, Hiking Yoga; gives you cardio and toning benefits of hiking, the mind-body treats of yoga, and the brain-and-mood-boosting effects of spending time outdoors. And when the instructor tells you to feel the earth beneath your feet or turn your face to the sun, you'll be able to do exactly that. (Drop-ins $20; yoga hikes take place in 14 cities so far—find one near you.

Calorie counts are based on a 150-pound woman working out for 60 minutes, using data from the book Exercise Testing and Prescription, by David Nieman.

Try Pogo Running (800 calories*)

Kangoo Jumps shoes look like moon boots on top of collapsible hoops, and their spring is intended to make you feel like you're running in zero gravity (or at least little gravity). The company says that the shoes protect your joints by reducing ground impact by up to 80 percent and also claims that you can burn 30 to 40 percent more calories than you would by running normally. A Rollerblade-ish fad? Maybe. But that shouldn't matter to treadmill joggers who like the way the rubberized belt cushions each step but hate how running in place makes them feel like a sad hamster. (Kangoo-Jumps.com, from $229)

*Possibly as much as 800 calories, if you can keep up a good pace for an hour

Try Sharing a Real Bike (286-573 calories*)

If you've already had an opportunity to experience one of the bike-sharing programs in cities like Denver; Washington, DC; Minneapolis; or most recently, New York, then you know that those miles can quickly add up. And while you won't get the same tank-soaking workout as you would in a spinning class, you will get to your destination faster than walking and in a better mood.

*Calories vary with your route, speed and number of pit stops. This is for 60 minutes of city riding, light effort to moderate effort.

Try Cardio Tennis (500–600 calories)

Oh, the catharsis of slamming that blue rubber ball against the walls (whack! for the impossible-to-impress client; whack! for the crash-prone browser)... but doesn't that indoor court look an awful lot like your office cubicle? Take your game to an outdoor tennis court (find one here), where you can get some fresh air while gaining a fresh perspective. To amp up the burn, try Cardio Tennis, which offers an interval-training approach to the sport. You'll take part in games that will ensure you're constantly swinging your racquet, as well as cardio drills like karaoke steps and high knees. Instructors say that this helps you get a full-body workout and burn more calories than singles or doubles does. (More info and program locations at CardioTennis.com.)

Try Playing in the Park (430 calories)

With the exploding popularity of boot camps and DIY interval workouts, every park is now an ersatz gym. And some are pretty advanced: The new Fitness Zones from the Trust for Public Land even offer free outdoor elliptical machines and other Nautilus-type equipment (there are currently 81 locations, mostly in California and Florida, with more coming soon to Newark, Boston and other cities). You can still get a serious muscle-building workout with just a park bench: Try a series of push-ups, triceps dips and step-ups. Jungle gyms are also great way to practice pull-ups. Start with your feet on the ground until you get the mechanics of the move, then do a little hop for momentum, and eventually (3 months, maybe), you'll be proving to yourself (and to researchers) that women can do them.

Next: 4 playful workouts the kid inside of you will love