A glorious sporting career is coming to an end. Usain Bolt, an eight-time Olympic champion, the fastest man in history, will retire after the IAAF World Championships in London, which run from August 4- 13.

He is a sprinter who has broken records and left a legacy. We look into the numbers which make the 30-year-old Jamaican the greatest sprinter to have lived.
All four of the fastest 100m times in history belong to Bolt. Known in his early years as a prodigiously talented 200m runner, he burst onto the 100m scene by breaking the world record in New York (9.72) in 2008. Eleven weeks later, in Beijing, he improved on his time, clocking 9.69 as he claimed his first Olympic title.
He has dipped under 10 seconds in the sport's blue riband event 50 times -- putting him fourth on the sub-10 seconds all-time list. But Bolt, who last lost in 2013, is a man who peaks for championships. Three of his quickest times have been achieved on his way to winning either Olympic or world gold.
His times have been in decline over the years and the days of him breaking world records are clearly over. The gold-medal winning times aren't what they used to be -- from 9.58 in Berlin to 9.81 in Rio last year.
Only once this season has he gone below 10 seconds, though he should add to that tally in London this weekend.
Men of Bolt's size aren't usually speed freaks. His frame is meant to be an obstacle in an event which requires explosive power out of the blocks.
"We never saw prior to Usain Bolt a sprinter who is 6'5 running the 100m," former Olympic champion Michael Johnson tells CNN Sport. "Typically, that type of athlete would not be able to get out of the blocks and get through the drive phase in the first 30m or so when short, powerful, massive pressure and power is what's required."
With his height and weight, the world record holder would not look out of place on the basketball court. He is notably taller than his rivals, as well as the greats of the past. Christian Coleman, the fastest man in the world this year, stands at 1.75m, while his long-time rival Justin Gatlin is 1.85m.
Scientists have been studying the secret of Bolt's supersonic speed for years. He hit a top speed of 44.7.8 km/h between 60m and 80m during his world record 100m sprint in Berlin and is almost as explosive as smaller sprinters in the early stages of a 100m race.
Once out of the transition phase, his height comes to his advantage -- the Olympic champion needs only 41 strides to cover 100 meters while other elite runners need 43 or 45. And once he has reached top speed, he is able to maintain his momentum more efficiently than others, which is crucial in a race won not by the person speeding up at the end but slowing down the least.
Bolt -- who since 2008 has contributed to 40% of the country's medals at Olympic Games and World Championships -- is as cherished as the late singer Bob Marley in his homeland.
Over 30,000 watched him run his last race on home soil in June. But Bolt is also universally loved. Not only is he one of the wealthiest sportsmen on the planet -- according to Forbes he is 23rd on the list of the highest-paid athletes in 2017 -- but he is also one of the most popular too, with over 7m Instagram followers and 4.7m on Twitter.

By Mark Oliver and Aimee Lewis, CNN