Looking for a way to break up your fitness routine? Look no further than your local tennis center. But don't worry if your serve is a little rusty.

Cardio Tennis is not about who wins and loses, according to Michele Krause of the Tennis Industry Association.

"We let the players play off of two bounces, they play the out balls," she said. "So there aren't all these real strict rules and parameters and guidelines that you have to follow in traditional tennis."

Krause was at Raleigh Racquet Club this week to serve up some enthusiasm among local tennis pros over Cardio Tennis, a group exercise program that is re-energizing tennis courts across the country.

"True tennis players know what a great workout tennis is," said Krause. "Most people though, are recreational or maybe lower skilled players and their perception is it's not giving them a good workout."

Armed with baskets of tennis balls and a boom box, Krause demonstrated the ins and outs of the program.

"It's fun because it brings in just the game playing that we lose track of when we're just focused on getting more fitness," said Joy Dempsey, a fitness instructor from Raleigh, who wants to offer Cardio Tennis to her clients. "I can look at my caloric burn for an hour taking the class and it comes in right below running my five-mile course in the morning."
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Participants use heart rate monitors to measure the intensity of their workouts. Krause said the average female burns 300 to 500 calories in a one-hour class, while a man can burn 500 to 1,000 calories per hour.

Cardio Tennis programs are offered at tennis and fitness centers as well as recreational facilities across the country.  The Tennis Industry Association publishes a list of certified Cardio Tennis programs on its website, CardioTennis.com