by curveballerguy124 » Thu Aug 08, 2019 5:05 pm
Hip thrusts (a.k.a) Glute bridges, huge exercise for pitchers, along with DL's and front squats..... Aside from the obvious weight training portion for building speed. Arm whip development, that is number one in my books.
However, it has to be the result of hip drive. now you can create arm-whip without hip drive but you limit the threshold of speed when you do that. Developing the mechanics of vertical stacking, basically producing power from the ground up should be your strongest fundamental....So that being said don't focus on weighted balls or anything that isolates the upper body or just the arm you wont develop speed that way...
I recommend doing a lot of throwing from the sideways position(open) using bands on the legs(can't stress that enough), half circle only so she is forced to develop arm whip. Remain open thru delivery, lead with your elbow, brush the leg with your pinky, and finish pointing with your thumb...... Repeat over and over, lots and lots of sets, focus on the ground up!!! Sprints, box jumps, burpees these all help as well.
Hope this helps and remember, learning to produce power from the ground up will allow your athlete to reach their max potential regardless if they are a good athlete or not, so essentially they become the best they can be thru mechanics...