Hello: I am a fitness enthusiast. In our opinion, you can exercise your forearm, biceps brachii, triceps brachii and your back muscles with dumbbells, which will obviously improve the transmission of strength and speed when you throw the ball! As for whether it will become shorter, I can definitely answer that you won't! ! The reason why weightlifters are not tall is because of the particularity of weightlifting, which involves technical problems, so we won't mention it. You exercise dumbbells instead of barbells. You have to understand that no matter how hard you exercise dumbbells, it will not affect your height! Moreover, even a barbell depends on the different muscles you exercise, so don't worry! !