For years it has been assumed that racehorses had reached the limit of their abilities, but new research suggests they are getting faster.

A study at the University of Exeter of 616,084 race times run by more than 70,000 horses shows that winning speeds have increased greatly since 1850.

Dr Patrick Sharman, from the university's Centre for Ecology and Conservation, said: "There has been a general consensus over the last 30 years that horse speeds appeared to be stagnating.

"Our study shows that this is not the case and we have revealed that horses have been getting faster.

"The challenge now is to find out whether this pattern of improvement has a genetic basis."

The study also shows that both the historical and current rate of improvement is greatest over sprint distances.

That comes as no surprise to Classic-winning trainer and qualified vet Mark Johnston.

Speaking at Beverley Racecourse, he said: "The main focus of breeding tends to be more on speed than endurance, so you'd expect to see the greatest improvement there.

"You've only got to look at the times the horses are running to see the improvement. Only last week one of my horses, Oriental Fox, broke the track record at Ascot."

Chief executive of Beverley Racecourse, Sally Iggulden, said: "It takes a great horse to beat a track record, and most of the ones here at Beverley are pretty old.

"But course management is much better now, so horses don't often run on the bone dry, very fast courses of the past."

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Factors thought to have contributed to the lower race times include genetics, training techniques, and altered riding styles, particularly in the 1970's when Lester Piggot pioneered using shorter stirrups.

A former jockey, trainer Charlie Mann told Sky News he is a little sceptical about the findings.

"The track record for Sandown was set by Arkle. And that was back in 1968," he said.

If the research is correct, horses like Arkle and Secretariat, whose phenomenal records set on the dirt tracks of the US in the 1970's still stand, must be the exceptions to the rule.

But the findings are clearly backed up by the incredible Frankel.

Officially the highest-rated racehorse since records began, he retired unbeaten only three years ago.

Source: Sky News