MAYBE YOU’VE ALREADY escaped the gym for an occasional walk around the neighborhood, a run or bike ride on the streets, or a swim in the pool. But you can get even further away from the gym—in mind, body and spirit—by spending some serious cardio time where the air is pure and unfiltered. More important, you’ll blaze more calories, improve your overall strength and balance, and hang on to your sanity.

“The time goes by faster in a natural setting because your senses are bombarded by so much stimulation,” says Denver-based Charlie Hugo, personal trainer at the Athletic Club at Denver Place.

Hugo knows a thing or two about the fitness perks of exercising outdoors, having completed two 100-mile mountain-bike races and countless trail runs in the Rockies while training for Ironman-distance triathlons. “One major benefit,” he adds, “is that you burn more calories because of the increased muscle recruitment demanded by the varied terrain.”

We’re not advocating a total cardio shakeup. We’re suggesting only that you change venues, not activities:

– If you walk or run the treadmill, you can take a break from the machine and hike or run trails.
– If you climb simulated hills on a stationary bike, you can wheeze up real ones on a mountain bike.
– If you’re a lap swimmer, you can stop counting and start stroking along the shoreline.

In each case, you’ll enjoy sunshine, fresh air, and vistas far more interesting than the talking heads on CNN.

Mountain biking

Why outside? “The uphills and downhills of mountain biking—and the wind gusts that come at you from different directions—combine to enhance calorie burn, core strengthening and balance,” says personal trainer Charlie Hugo. “Just think of all the muscles you use, for example, to shift your weight around a hairpin turn.” Wouldn’t you rather roll down a shady trail than pedal in place in a gym?

Muscles worked: Major: Hams, quads, calves, glutes, hip flexors. Minor: Abs, chest, delts, trapezius.

Calories burned: 410-550 per hour

Eqipment & apparel: Durable, off-road-ready mountain bikes with front suspension (to absorb shock) start at $300. A helmet, mountain-bike shoes, padded bike shorts and bike gloves total another $150 to $200. Take water, sunscreen, sunglasses, a trail map and a cell phone.

Best places: Many county, regional and state parks are laced with dirt roads and trails; call the park to request a trail map and ask if all trails are open to bikes. At vacation areas, rent a mountain bike and ask the shop proprietor where to ride. Or visit

Practical tip: At home, practice riding around obstacles and over curbs so you’ll be ready for tight turns and big rocks on the trail.

Just for kicks: Try a different trail route each time to keep your rides fresh and adventurous.