Only a dozen more thoroughbreds have won the coveted Triple Crown of horse racing in the 100 years since Sir Barton became the first to win all three big races — the Kentucky Derby, the Preakness Stakes and the Belmont Stakes — in the same year.
American Pharoah's sweep ended a 25-year Triple Crown lull in 2015. Three years later, Justify's sweep made him the 13th horse ever to win the Triple Crown.
But which of the 13 champions had the fastest time overall?
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That would be horse racing legend Secretariat, who earned the three-race title in 1973 and holds the fastest combined time for each of the three races. Secretariat still holds the record for the fastest Kentucky Derby winning time.
Why aren’t race horses getting faster?
It’s possible that thoroughbred horses have already reached their maximum record speeds, according to a 2008 paper by Mark Denny, a Stanford biology professor who studies biomechanics.
Meanwhile, human speeds, particularly in men’s racing, may have not peaked just yet as we continue to see racers break records. But those increases in speed are expected to be less and less over time, Derry noted.
In asking whether there are absolute limits to the speed at which animals can run, Derry used statistical models to analyze running speeds for greyhounds, thoroughbred horses and elite human athletes.
“Horse and greyhound speeds seem to have plateaued,” Derry said in an email. “In general, there does appear to be some room for humans to increase their speed, but speeds for women in short races seem to have plateaued already, and speeds at all distances give signs of plateauing.”