Olympic Legends: Athletes who redefined the definition of champion

First Briton to win the Tour de France, Bradley Wiggins has won four Olympic golds, one silver and two bronze medals on both - track and the road. A medal at Rio will be 34-year-old cyclist's eigth overall, which will make him the most decorated British Olympian of all time.

The current women's world no 1, Serena Williams has been a dominant performer at the Olympic Games, in both singles and doubles events. The 34-year-old has claimed four gold medals in total - 2000 Sydney, 2008 Beijing and 2012 London games. At Rio, Serena will look to defend both of her gold medals, in singles as well as doubles events.

The fastest man on earth, Usain Bolt single-handedly drew sports lovers' attention towards track and field games with his super-human performances. The Jamaican, who competes in 100 meters, 200 meters and 4x100 meters relay events at Olympics, won all three possible gold medals at the 2008 and 2012 Games in Beijing and London respectively. He was recently declared fit to compete in Rio after suffering a hamstring injury.

Al Oerter was the the first athlete to win a gold medal in the same individual event in four consecutive Olympic games. The discus thrower was inducted in the IAAF Hall of Fame in 2012 for his achievements on the international circuit. Many rate the American as the greatest of all time, considering a discus thrower can only win one gold medal at each Olympics, contrary to majority of other sports where multiple medals can be won.

One of the most decorated Olympians of all time, Michael Phelps has won a total of 22 medals in three Olympiads he has participated in so far. The American swimmer holds the record of most number of gold medals with 18 to his name, two times more than second place holder Larisa Latynina. Rio 2016 will most probably be the 31-year-old's last mega-challenge after he came out of retirement to compete in the quadrennial event.