How does age affect a horses racing ability?
Horses can be immature until age 2 or as late as 5 years (!). Once they hit their peak, it can last anywhere from ~1 year to ~3 or even 4 years. Once they are past their peak, they again suffer in their racing ability, though this may be slightly less than when they were immature, as they now have racing experience. (Babies suffer a minor penalty until they get used to racing).
