That makes it important for bettors to know their horses and try to determine which one most likely will overcome the handicap and win the race. The entry-level Maiden Race circuit is the most common horse race in which weights are used to handicap thoroughbred horses and make the races more competitive. Allowance races also utilize weight-based handicapping as many horses are in the range of two years of age and vying to earn a spot in the top levels of racing where weights usually aren’t used but still can be in some prestigious races. Because horses generally are fully mature by the time they reach three years of age, top thoroughbred races, such as the Kentucky Derby, Preakness Stakes and Belmont Stakes, do not need to use them. Races run by younger horses at the top tracks still likely will be weighted to handicap more physically mature horses and give younger horses a better chance at winning.