USES. Although the Thoroughbred is primarily bred for racing, the breed is also used for show jumping and combined training because of its athleticism, and many retired and retrained race horses become fine family riding horses, dressage horses, and youth show horses.he Thoroughbred is a horse breed best known for its use in horse racing. Although the word thoroughbred is sometimes used to refer to any breed of purebred horse, it technically refers only to the Thoroughbred breed.