Next to aerobics, Zirnheld especially likes Pilates. The recreation department began offering a combination yoga-Pilates class, called "yoga-lates," last summer.
"I still have to do the cardio (cardiovascular). I like getting my heart rate up and feeling like I pushed myself up. Then, the Pilates hopefully takes care of the damage I did. It's really good for you to stretch those muscles and get in that deep breathing," Zirnheld says noting that she likes to incorporate Pilates into her step class, especially at the end.
In addition to the guilt factor, another reason Zirnheld says people may flock to Monday night classes is the instructor, Kathy Matherly.
"Kathy is my hero. She gives me the hardest workouts," Zirnheld says.
Matherly, who began teaching seven years ago, says she gets some of her ideas from watching workout shows on TV while getting ready for her job as office manager at Harrodsburg Middle School. One of the latest things they've added at the recreation department is ramps.
"They are geared for the gluteal muscles and the hamstrings, the back part of the your body."
She also is an alternating instructor for the yoga-lates class on Wednesdays. She says holding the yoga poses requires a lot of stamina.
"It's a really good workout - you don't realize it until you do it."
She likes Pilates because it targets the core of the body - the abs and back.
"You take care of your spine and your back and your whole body is going to be healthier."
She thinks women especially benefit.
"I like Pilates for the fact that it gets the core and it's a lengthening type of exercise, which is especially appealing to women."
Her advanced step class, which lasts an hour and a half, incorporates abdominal work and free weights for 30 minutes.
"We do at least 35 minutes of cardio. Then we go right into free weights and we do some ab work. You can incorporate some Pilates and ab work."
Matherly schedules her classes for the evenings, but still finds time to run about 3 miles four mornings a week.
"We hit the pavement by 6 o'clock. It's dark, but I have a running buddy."
Marlene Settles, who taught aerobics for 15 years and did kickboxing for two years, now focuses solely on Pilates. For the past two years, she has taught an hour-long class twice a week at Centre College and twice a week at McDowell Wellness Center. She predicts that she will be a lifelong fan of this form of exercise.
"It's just something I know that I can do for many years. It's for any age. It's for everyone. I have teenagers in my classes and my mom started when she was 75."
Settles says she does not worry about injuries.
"You don't have any stress on your joints. It's nonimpact."
Unlike some exercises that people tire of, Settles looks forward to Pilates.
"You don't have to get out there and sweat. It's not exhausting, but you can really change your body."
To mix things up, her classes switch from six weeks of mat work to six weeks of using a Swiss exercise ball.
"The ball is a lot more challenging because you're not on a flat surface. You're on a surface that can move."
Aquasize, another type of exercise to consider at the wellness center, is making a big splash because it doesn't put stress on the joints.
"A lot of people start off in the pool if they have an injury," says Susan Cunningham, who has specialized in water aerobics for three years. "I started it when I was pregnant with my first child. A lot of women like it because you won't build big muscles. It's better cardio exercise. You actually burn more calories by swimming. Aqua jogging is great, too, because you tone without stress to any joints."
She also offers water yoga, which is becoming very popular.
"I'm a big fan of not using weights, so a lot of the training I do is based on water resistance and using your own body weight. Yoga was what pushed me into that. It's wonderful toning."