Horse Racing Sprinters/Stayers

Question
Can you tell me what is it in a horses composition to make a horse suited to short sprinting races compared to long staying/endurance races?

Answer
HI JIM IN AUSTRALIA. WELL A SHORT COUPLED HORSE WITH A BROAD CHEST AND POWERFUL HIND END SHOULD MAKE A GOOD SPRINTER. I DON'T THINK SIZE HAS ANYTHING TO DO WITH SPEED OF A HORSE. OF COURSE I HAVE HAD ALL KINDS OF HORSE THAT WOULD SHOW SPEED AND THEY DIDN'T LOOK AT ALL LIKE A SPRINTER. ANOTHER THING I LOOK FOR IS GREAT WIDTH AND DEPTH UNDER THE HORSES JAWS. MEANS  THAT A HORSE HAS A BETTER BREATHING CAPACITY WHEN RACING. A HIGH BAND END ALSO MEANS MORE POWER TO PUSH AWAY FROM THE GATES. HOPE THIS ANSWERS YOUR QUESTION  THANKS ED HESS