well it's not just jumping, i mean if you workout your vert, you will be more explosive, you can run faster, react faster, you can get stronger...vertical jump can help you in many aspects, not just jumping for rebounds or dunking...

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"Look me in the eye. It's ok if you're scared. So am I. But we're scared for different reasons. I'm scared of what I won't become, and you're scared of what I could become. Look at me. I won't let myself end where I started. I won't let myself finish where I began. Look me in the eyes. I have something more important more courage. I have patience. I will become what I know I am."
-- Michael Jordan