Former tennis star Anna Kournikova has been chosen as the new spokesperson for Cardio Tennis. Kournikova, who reached a career-best No. 8 in singles, and No. 1 in doubles, will appear in Cardio Tennis public relations campaigns to promote the program.

“The sport of tennis gives your whole body a workout, and Cardio Tennis takes it up another level,” says Kournikova. “It's designed for players of all ages and levels from beginners to advanced. You get a great workout and burn tons of calories. Plus, it's a lot of fun—certainly more interesting than working out in the gym. And to top it off, you'll improve your tennis, too.”

Kournikova's interest in Cardio Tennis started when she was scheduled to appear on the popular NBC show “The Biggest Loser.” The Russian-born 29-year-old suggested to the show's producers that she run a Cardio Tennis workout.

“I knew it would be the perfect on-court workout for the contestants to use to get in shape,” she said in a statement.

The episode aired on Oct. 5, with Kournikova putting the 15 contestants through a fat-burning Cardio Tennis workout as a key part of the show's weight-loss and fitness program, encouraging them to keep moving and keep their heart rate up.

Cardio Tennis was developed in 2005 by the Tennis Industry Association
in conjunction with the U.S. Tennis Association as a fun and healthy
exercise to get in shape and lose weight. It is a high-energy fitness
activity that combines the best features of the sport of tennis with
cardiovascular exercise, delivering the ultimate full-body,
calorie-burning aerobic workout. There are now more than 1,700 Cardio
Tennis sites in the U.S. To find out more about Cardio Tennis, including
where to find a program near you, visit CardioTennis.com. (The new
website, featuring Kournikova, is currently under construction and will
be launched in the coming weeks.)

The 29-year-old Kournikova joined the pro tour in 1995, reaching a
career-high ranking of No. 8 in the world in singles, and No. 1 in the
world in doubles. Kournikova won 16 WTA Tour doubles titles, winning the
Australian Open doubles title twice (1999 and 2002) with partner
Martina Hingis. While Kournikova hasn't played on the WTA Tour since
2003, she continues to promote the game of tennis by participating in
exhibition matches and charitable events throughout the U.S. and the
world. She will also be entering into her ninth season with the World
TeamTennis Pro League, where she currently plays for the St. Louis Aces.

A huge supporter of tennis for players of all ages and abilities,
Kournikova is heavily involved in causes that promote health and
fitness, particularly for families and children. She currently is an
ambassador for the Boys & Girls Clubs of America, Cartoon Network
and the USO, for which she visits military bases and speaks to families
and children. She also spends a great deal of time as a global
ambassador for PSI, a global health organization, educating young people
around the world on making healthy and educated decisions regarding
health and lifestyle.