Anna Kournikova

Anna Sergeyevna Kournikova was born in Moscow, Russia,and received her first tennis racket at the age of 5. She began playing two times a week via a children's program and entered a professional tennis academy two years later, dividing her time between her studies and tennis instruction. In 1986, Kournikova joined the Spartak Tennis Club, where she met Larissa Preobrazhenskaya, one of Russia's top instructors, who saw raw talent and began coaching the budding athlete.

At 10 years old, Kournikova signed a management deal and hopped on a plane to Florida to begin training at the renowned Bollettieri Tennis Academy in Bradenton. She made her professional tennis debut at age 14 in the Fed Cup for Russia, where she was the youngest player to compete and win. Kournikova made her Grand Slam debut at just 15 years old when she competed at the 1996 U.S. Open. She faced top-ranked Steffi Graf (who went on to win the tournament) during the fourth round of competition. Though she did not win, her performance at the U.S. Open was enough to raise Kournikova's professional ranking from No. 144 to No. 69. That same year, she joined her fellow Russian athletes to represent their country at the Olympic Games in Atlanta, GA.

At 16, Kournikova became the second woman in her sport to reach the semifinals round during her debut appearance at Wimbledon, considered the sport's most prestigious tournament. Facing Swiss-born Martina Hingis in the semifinals, she eventually lost the game, but tennis experts were wowed by Kournikova's footwork, speed and aggressive baseline play whenever she took to the court. These same groups also criticized her for making too many unforced errors during matches and for wearing rather provocative uniforms.

Ironically, Kournikova won her first Grand Slam title in the women's doubles with Hingis as her partner. The pair finished first during the 1999 Australian Open. Kournikova and Hingis were again crowned the Australian Open women's doubles champions in 2002. Kournikova retired from professional tennis in 2004 due to chronic lower back trouble, yet she frequently competed in exhibition matches for charity.

Apart from her athleticism, even non-sports fans could not help but notice Kournikova's modelesque features. She landed on People magazine's "50 Most Beautiful People" list in 1998 and became one of the most-searched athletes on the Internet. Kournikova continued to mine her sexy assets by appearing in various men's magazines like Maxim and FHM, as well as in the highly publicized Sports Illustrated swimsuit issue" in 2004. The tennis bombshell made her feature acting debut with a cameo in the Farrelly brothers-directed comedy "Me, Myself & Irene" (2000) starring Jim Carrey and Renee Zellweger.

Kournikova made a guest appearance on NBC's hit reality series "The Biggest Loser" during a tennis workout challenge. So successful was her appearance, she was invited back to the show the following season, replacing Jillian Michaels as the celebrity trainer alongside Bob Harper. However, after only one season on the hit show, Kournikova announced in November 2011 that she was not returning for the show's 13th season.