The document discusses discus training drills using a D-ball (medicine ball with a handle). It recommends practicing technique in sets of 4 drills performed 3-5 times each. Drills include a standing throw, 180 throw, and run through to develop core movement and basic technique. Practices are especially useful for adolescent athletes during growth spurts to relearn coordination. D-balls allow high volume, low intensity training inside a cage for safety.