Lot of good things going on here. She gets a good "runner's start" off of the pitching plate. Her initial move with her glove is straight to the catcher, which helps her get her shoulders to open properly. Her stride is long and looks to be at least the height of her body. She lands with a flexed front knee, pushes up to firm up the front side and is balanced. Overall a very good pitcher with a lot of upside.
Here are the things I'd work on. While the initial move with the glove is to the catcher, I feel that she is "swimming" out with the glove a little bit too much. It could cause her to lose shoulder alignment before she wants.
On the first part of the video, if you stop the video at foot plant you can see that her foot is pointing at a 1 o'clock position. Now look at what that does to her knee and the stress that it puts onto the ACL. Girls are more susceptible to injuries to the ACL so she should do what she can to stabilize it while pitching. A good start would be to get her to land at more of a 45 degree angle; which is somewhere between 1 0'clock and 2 o'clock. Stopping the video at foot plant you can also see the glove swim described above.
Nice back yard pitching set up. My compliments dad. I study hitting more than pitching but I did have a pitcher in the family and much about movement transfers from any activity to the next athletic activity. To me, she never gets her hips leading out in front and as a result she's got her shoulders out over her hips too much. I'd like to see it in slow motion but I bet if she leads with the hips a little more it will both be easier on her body and she may get a whippier arm action. Looks like a good athlete.
Is she throwing a fastball? If so, her arm is really messed up.
Take a look at this, and look at her arm position after release.
Look at the arm muscles. They are bulging from the shoulder to the wrist. What she is doing is "cutting off her follow through" to keep the ball down.
Her hand never comes above her waist. She is using her arm muscles to stop her follow through. She is losing speed. She might even hurt her shoulder because she is "slamming on the brakes".
Here is Finch's follow through:
Do you see the difference?
The idea is that the arm is a rubber band that is released when the ball is thrown. The arm and wrist after the ball is released should be relaxed. If they are relaxed, the arm will rotate upward.
So, she needs to practice letting her arm rotate up. To practice this, take her to a ball field somewhere. When she starts relaxing the arm and finishing her follow through, the ball is going to go all over the place until she gets used to it.
Wow! She looks very athletic, must have leaped out about 8 feet. I had a college pitcher with a similar style. We added some core, low back and bungie exercises that helped improve her game, especially in the late innings. I think she is off to a great start. Work on her slight lean, opening up, and try to keep her weight back (body angle). Others will talk about her arm circle. Good luck.
the stop action shots really speak volumes. it is hard for me to see all of that from the bucket. i clearly see the swimming, plantfoot at 12. i'll try & figure out how to open it up a bit more. do more one legged drills for the leaning.
i don't know how or why we stoped finishing the pitch with our delivery arm. i see what you mean. i've been trying to get her to loosen up a bit on follow through. i didn't realize that her lack of finishing was so extreme.