Help??Lose in velocity too much lifting???

There can only be 3 causes I guess.

1) Gun consistency - same gun, same reader?

2) Technique changes - do you have before and after video?

3) Injury- causing technique changes

The 'weight room' has nothing to do with it.  He can only get faster with more (conditioned) mass.

Pitch coach states he lost/losing flexibility?I do see your point.2016 went over to high school to lift during 8th grade.He wanted to get new guy thing over with before others showed.2016 put on 30lbs.while gaining @ couple of inches picked up @ 10 mph.He has either stopped or is slowing growth this last year.grew less than 1 inch.2016 has always been one of those kids that just had good mechanics.If he was sitting at were he was last fall well then yes its mechanics of some sort.I realize he's at the point its a lot of small things and repatition to gain more velo. but to lose @5.

Pitching is about speed of movement and repeatability, not strength.  The pitcher is trying to move a 5oz baseball as fast as he can using his entire body as a whip, not push a 300lb tackle off the line.  Extra muscle typically reduces flexibility.

Velocity comes from how explosively and smoothly the pieces fire in sequence, not the amount of muscle in the throwing arm.

My son's regimen has been consistent from HS through college.  Lots of plyometrics for explosive movements.  Core strengthening exercises.  Lots of bandwork for the arms, shoulders and back.  Fair amount of cardio.

The colleges we visited before signing pretty much all had this routine for their pitchers.

Hope this helps

CVJ

You can become muscle bound lifting weights, if you lift improperly.Baseball, Softball, Volleyball, Basketball, Football all rely on explosive movements and flexibility (yes, football linemen need to be flexible and quick if they want to be effective).  If you're following a good SAQ program (strength, agility, quickness) you'll start out by developing a solid strength foundation prior to the more advanced work (i.e. most plyometric routines).  As part of a good SAQ program your athlete should also be involved in post workout stretching as well as using foam rollers.  Besides being a denizen of the weight room my son finishes his workout with a stretching routine useful for pitchers and kickers to keep him flexible.  It helps his hitting, pitching, punting, long snapping, catching, and power forward play.

It sounds like he's lifting without a purpose and without proper supervision/training.  This can leave him unbalanced and tight, as well as not developing properly for baseball or football.  The solution is not to stop lifting (free weights are used in college pitching conditioning as well body resistance and band work) but to learn how to lift correctly and with a qualified trainer.