How can i gain velocity in the offseason?

I am 5’7 and a sophomore in HS. My fastball hits, dare i say it, 68 mph :confused: . I want to hit at least 80 next year, is there anyway this can be accomplished? Impossible is nothing right? haha

My son was throwing 69 MPH last Memorial day. Six months later, he hit 84 MPH and averaged 80-82 MPH. It wasn’t easy.

He worked saw his deadlift go from 260 lb to 405. He threw medicine balls 2-3 times a week along with battle ropes. Long tossed 2-3 times a week. He also worked up his pullups to 3 sets of 20 a day.

This year he is adding power cleaning a 80 lb sandbag and is working up to 130. Also, he is using DeRenne’s weighted ball protocol.

He also changed his mechanics to get more hip drive and more scapular loading.