The Big Question: As the 100m world record falls again, how much faster can humans run?

By Mike Rowbottom, Athletics Correspondent 

Tuesday, 3 June 2008

Why are we asking this now?

Because Usain Bolt, a 21-year-old Jamaican, smashed the world 100-metres record in a race in New York at the weekend, clocking 9.72 seconds, two hundredths of a second faster than the previous best, set by his compatriot Asafa Powell in September last year. It was the 17th time the record had been legally broken since an American called Don Lippincott ran 10.6 seconds in 1912, and the eighth new 100 metres record set since 1991. The 10-second barrier was broken in 1968, the 9.90 barrier in 1991, and the 9.80 barrier in 1999. Now the 9.70 barrier is in sight.