After one session of cardio tennis, Lanny Daise was hooked.

“First of all, I needed a shower,” Mr. Daise says of his introductory session in Kansas City. “But after that, I thought, ‘This is great. It’s like aerobics with a tennis racket.’”

The St. Joseph resident then sought to bring cardio tennis to his hometown. And now in its second season, the hottest trend in fitness is gaining a foothold in St. Joseph.

Cardio Tennis, a program developed by The Tennis Industry Association, has grown rapidly in popularity since it was introduced in 2005. In 2006, the United States Tennis Association offered 500 free sessions at locations across the country. Also in 2006, cardio tennis became a 50th anniversary partner of the President’s Council on Physical Fitness and Sports.

The St. Joseph Tennis and Swim Club began offering cardio tennis classes last spring. After the instructor left, management put the classes on hold. Today, the classes are back in St. Joseph.

“I’m very, very excited about it,” Mr. Daise says.

The workout has the hallmarks of circuit training combined with tennis drills. A tennis instructor and a personal trainer run the sessions. While participants are with the tennis instructor, they either hit back balls while running to different places on the court or practice different hits.

Eric Thacker, a tennis instructor, said the sessions are a way for beginners to pick up tennis skills quickly.

“You don’t have to be a tennis expert to give this a shot,” he says. “One of the best things about this workout is you can cater it to different skill sets and needs.”

Mr. Daise, who is a tennis enthusiast and on the board of directors for the St. Joseph Tennis Foundation, says the participants have ranged from tennis experts to those who didn’t know how to hold a racket.

“When you’re playing tennis, you have to know how to control the ball,” Mr. Daise says. “But in cardio tennis, it doesn’t really matter. You’re just supposed to hit the heck out of it.”

As participants move through these tennis drills, a personal trainer periodically picks out individuals or small groups for different exercises. According to Mr. Daise, these exercises range from sit-ups to leg pushes.

“It’s pretty much constant movement,” says Ron Selkirk, manager of the St. Joseph Tennis and Swim club.

Mr. Daise, who works out regularly on his own, says he enjoys having direction during this workout.

“You’ve got encouragement from the personal trainer,” he says. “It really helps motivate you.”

Mr. Selkirk says the trainer asks participants to check their heart rate during the sessions. The goal is to work out at 60 to 70 percent of one’s maximum heart rate.

“It’s the best range for calorie burning,” he says.

Mr. Daise says the workout is much more intense than 30 minutes on the bike or three miles of running.

“It’s a heck of a workout,” he says.

Cardio tennis sessions at the St. Joseph Tennis and Swim Club are open to the public and are held during the week and on the weekends. Contact the club for more specific times and dates.