Anna Sergeyevna Kournikova (Russian: А́нна Серге́евна Ку́рникова, IPA: [ˈanːə sʲɪrˈɡʲejɪvnə ˈkurnʲɪkəvə] (listen); born 7 June 1981) is a Russian former professional tennis player and American television personality. Her appearance and celebrity status made her one of the best known tennis stars worldwide. At the peak of her fame, fans looking for images of Kournikova made her name one of the most common search strings on Google Search.Despite never winning a singles title, she reached No. 8 in the world in 2000. She achieved greater success playing doubles, where she was at times the world No. 1 player. With Martina Hingis as her partner, she won Grand Slam titles in Australia in 1999 and 2002, and the WTA Championships in 1999 and 2000. They referred to themselves as the "Spice Girls of Tennis".Kournikova retired at the age of 21 due to serious back and spinal problems, including a herniated disk. She lives in Miami Beach, Florida, and played in occasional exhibitions and in doubles for the St. Louis Aces of World Team Tennis before the team folded in 2011. She was a new trainer for season 12 of the television show The Biggest Loser, replacing Jillian Michaels, but did not return for season 13. In addition to her tennis and television work, Kournikova serves as a Global Ambassador for Population Services International's "Five & Alive" program, which addresses health crises facing children under the age of five and their families.