Fitness: Great Summer Workouts (cont.)

If you're unsure of your ability or if it's been a while since you've been in a canoe, Calabrese advises taking lessons. Just learning will be a workout in itself.

"It's great for the shoulders," she says, "but it's also great core, great obliques, and great back work." In addition, she says, the legs work as stabilizers.

Be conscious of muscle balance, she says. Don't always turn the canoe in the same direction. If you're circling the lake, reverse the circle. Row on alternate sides of the boat, or use a longer, double-sided paddle, which makes balancing even easier.

And enjoy the ride. "It's different, it's fun and it's a great way to see the lake, from a canoe," says Calabrese. "It feels good just to be out in nature and listen to the sounds of the water."

If you have no access to a canoe or boat, you have other options. Jesse Pittsley, exercise physiologist and program director for the exercise science department at Winston-Salem State University in North Carolina, knows the lake scene well.

"My parents live on a lake," he says. "We have a rocky beach by my parents' dock. We go out waist deep and grab around for rocks at the bottom of the lake and see if we can throw them to the shore."

This friendly family competition becomes a workout for the shoulders and abdominals (particularly the obliques). Before you know it, you're exercising and burning calories.

Working Out in the Mountains

Want a whole-body workout in rocky and mountainous terrain? Try pole hiking, says Calabrese.

What you'll need are a set of aluminum, rubber-tipped poles and a good pair of hiking shoes. The poles costs between $70 and $100 and are sold at some sporting goods stores or at walkingpoles.com.

Using the poles allows you to involve the upper body in activity that normally works mainly the legs and glutes, says Calabrese. "You move with quicker, smaller steps, your arms are pumping and it's almost like race-walking," she says. "The upper body motion really gets the heart rate going. It's a great way to add some intensity to your hiking."

It's also great for a beginner because using the poles reduces stress on the knees and distributes the body's weight more evenly.

The mountains are a great summer workout location because it's usually shadier and cooler in hilly terrain. Since you'll be gaining altitude, you may notice a drop in temperature as you climb. In desert climates such as Tucson, Ariz., where summers can be scorching, many people make the 40-minute drive up Mt. Lemmon to escape the 100-degree temperatures in the city. Then they hike in the 70-degree shade of pine trees.

Wherever your mountains are, exploring them is a great way to take a workout outdoors. Ayres says to bite off little chunks of the mountain, power walking for a specific amount of time, then resting and repeating.

"It can be a way of doing natural intervals," says Ayres, when you push the body, then rest alternately.