Other classes that combine workouts are also a growing trend. There's a barre class that is inspired by ballet and a fit wall that incorporates a rock wall into the workout. And the Maryland Athletic Club, with locations in Timonium and Harbor East, has recently added classes such as Yo Pi Chi, a combination of yoga, Pilates and Ai Chi. It's practiced in a pool of warm water.

Ann Shaw, aquatics director for MAC, said most of the water classes are full each day. They draw a combination of people who are injured or unable to work out on hard surfaces, pregnant women and those who just like the pool.

"People come in the summer to the pool because it feels good," she said. "But they like it and come in the winter too. They don't miss a day because it feels good when they leave."

Shaw said the pressure from the water means people are working out harder. Their hearts add 17 beats a minute in a pool, and she estimates a 30-minute workout in the water offers the same cardiovascular workout as 60 on land.

Shaw and Meadow Mill owner Nancy Cushman said good instructors are key to making classes enjoyable as well as physically challenging. They said they keep up on all the new offerings around the country and often make up some of their own based on the needs of students.

Cushman said the only class that has faded away has been belly dancing, and that was because the well-liked instructor moved to teach a different class.

"People keep coming back because they feel a connection," she said. "If the instructors love what they do, it's fun for everyone."



Fun fitness classes

Aerial classes

Offered at:

Meadow Mill Athletic Club, Baltimore. meadowmill.com (aerial dance and strengthening)

Canton Club, Baltimore. cantonclub24.com (air yoga)