Washington, November 28 : A Stanford University researcher has predicted that male sprinters may one day break Usain Bolt''s current world record of running 100 metres in 9.69 seconds, created at the Beijing Olympics this year, by covering the same distance in 9.48 seconds.

Biology professor Mark Denny, who himself has been a marathon runner, came to this conclusion after scrutinising the running performances of humans and two other famous racing species—dogs and thoroughbred horses—to find how close modern runners are to their species'' peak performances.

Having found records dating back to the 1920s for dogs and the 19th century for humans and thoroughbreds, Denny looked to see had any of the species'' performances already levelled off.

Describing the process adopted for the study, an article in The Journal of Experimental Biology said that the researchers plotted the annual top running speeds for all three species over the years, which made it clear that racing horses and dogs have already reached a plateau.

The study showed that there had been no improvement in the thoroughbred''s speed in the Kentucky Derby since the 1940s and two other major US races since the 1970s, while dogs'' performances also levelled out in the 1970s.

According to the study report, the increasing dog and thoroughbred populations had not improved the animals'' performances.

Denny, however, feels that “chance might still turn up a faster animal,” and predicts that thoroughbreds could improve their top speeds by as much as 1 per cent in the
2012m Kentucky Derby, eventually peaking at a top speed of just over 17m/s.

Looking at the speeds of male race winners through the years, Denny came to the conclusion that men had still not reached their top speeds at any distance, and predicted that male 100·m sprinters could one day get the record down to an incredible 9.48s, running 0.23m/s faster than Usain Bolt''s current world record of 9.69·s.

Meanwhile, his study suggests that female sprinters'' top annual speeds levelled off in the 1970s, meaning that any improvement in their speed was not due to a population increase.

But Denny still feels that female sprinters have room for improvement too, and predicts that they could eventually knock more than 0.4s of the current 100m world record to cover the distance in 10.19s.

As regards marathon runners, Denny believes that males may cut the current world record, held by Haile Gebrselassie, by between 2min7s and 4min23s.

He also reckons that female marathon runners may eventually cross the 42,195m finishing line in 2h12min41s.

He says that Paula Radcliffe''s current world record of 2h15min25s is very close to his average prediction for the maximum marathon speed and suspects that female marathon runners could be the first group to approach his predictions and test whether they hold.

The researcher, however, still has to find out what aspect of physiology restricts runners'' performances, and is keen to determine what will prevent future gold medal winners from breaking Denny''s Limits. (ANI)