SHOCK! Horror! Hold the back page! Usain Bolt is, in all probability, not the fastest man who ever walked the planet - or ran on it, naturally. In his brilliant, updated story of the men's 100m Olympic champions, The Fastest Men on Earth, Neil Duncanson tells of Australian anthropologists discovering 20,000-year-old fossilised footprints sealed in mud showing that cave men from the Pleistocene Age were running at speeds of 37 kilometres per hour - barefoot, on undulating terrain, and armed with heavy spears.

"Scientists believe that these aboriginal ancestors would have been capable of speeds of more than 45km/h if they'd had the same modern advantages as Usain Bolt," Duncanson writes.

Bolt's average speed when he clocked his 9.58sec 100m world record at the World Championships in Berlin in 2009 was 37.58km/h. In old money, that's 23.35mph.

"Of course, these Stone Age fast men were also well motivated, either chasing dinner or being chased as dinner," Duncanson continues. "It is a widely held anthropological view that 21st century man is the worst example of physical manhood in history and that the comforts of modern life and a bewildering array of distractions have left him soft, slow and vulnerable.

"All the evidence points to the fact that Stone Age men would have beaten today's Olympic athletes out of sight - at everything."

Still, Duncanson's book (published next month by Andre Deutsch at (pounds sterling)18.99) does a fine job of chronicling the fastest men on earth in the modern Olympic era. It is a revision of the volume he produced in the run-up to the 1988 Olympics.

In that edition the chapter about the reigning 100m champion Carl Lewis looked ahead to the looming Games in Seoul and to the threat posed to the American by Ben Johnson. It touched, inevitably, on the aspersions already being cast on Johnson, whose name might be denoted with an asterisk at the foot of the result of the 1988 men's final but the tale of his rise and fall has been pivotal to the history of the fastest folk on earth since caveman days.