5. Usain Bolt
His 2008 season began with his first world record performance—a 100 m world record of 9.72 s—and culminated in world and Olympic records in both the 100 m and 200 m events at the 2008 Beijing Summer Olympics.
He ran 9.69 s for the 100 m and 19.30 s in the 200 m, and also set a 4×100 m relay record of 37.10 s with the Jamaican team. This made him the first man to set world records in all three at a single Olympics.
The following year he further lowered his own 100 m and 200 m world records to 9.58 s and 19.19 s respectively at the 2009 World Championships. This made him the first man to hold both the 100 and 200 m world and Olympic titles at the same time.
His 2009 record breaking margin over 100 m is the highest since the start of digital time measurements
4. Carl Lewis
won 10 Olympic medals including 9 gold, and 10 World Championships medals, including 8 gold. His career spanned from 1979 when he first achieved a world ranking to 1996 when he last won an Olympic title.
Lewis topped the world rankings in the 100 m, 200 m and long jump events frequently from 1981 to the early 1990s, was named Athlete of the Year by Track & Field News in 1982, 1983, and 1984, and set world records in the 100 m, 4 x 100 m and 4 x 200 m relays.
His world record in the indoor long jump has stood since 1984 and his 65 consecutive victories in the long jump achieved over a span of 10 years is one of the sport’s longest undefeated streaks. Over the course of his athletics career, Lewis broke ten seconds for the 100 metres 15 times and 20 seconds for the 200 metres 10 times.
He was named "Olympian of the Century" by the American sports magazine Sports Illustrated and being voted "Sportsman of the Century" by the International Olympic Committee.
3. Michael Johnson
He won four Olympic gold medals and eight World Championships gold medals.Johnson currently holds the world and Olympic records in the 400 m and 4 x 400 meters relay. He formerly held the world and Olympic record in the 200 m, and the world record in the indoor 400 m. He also currently holds the world's best time at the 300 m. His 200 m time of 19.32 at the 1996 Summer Olympics stood as the record for over 12 years. He broke 44 seconds for the 400 metres twenty-two times, more than twice as much as any other athlete.
2. Ed Moses
won gold medals in the 400 m hurdles at the 1976 and 1984 Olympics. Between 1977 and 1987, Moses won 107 consecutive finals (122 consecutive races) and set the world record in his event four times. In his first international meet, Moses won the gold medal and set a world record of 47.63 seconds. Moses did not lose another race for over nine years. He set the world three times, won three World Cup titles, a World Championship gold, and earned his second Olympic gold medal.
1. Florence Grittiths Joiner
She stunned the world when — known as a 200m runner — she ran a 100m World Record of 10.49 in the quarter-finals of the US Olympic Trials. the next fastest time by any other woman in 2012 is 10.64. At the 1988 Summer Olympics, in the 200 m semifinal, Flo Jo set a world record (21.56) and then broke that record again in winning the final by 0.4 seconds with a time of 21.34.
Greatest Ever Sprinter VOTE
5. Usain Bolt