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.
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
Meadow Mill Athletic Club, Baltimore. meadowmill.com (aerial dance and strengthening)
Canton Club, Baltimore. cantonclub24.com (air yoga)