Is the shoulder used as a lever when driving out hard while using a backswing?

[abbygale]

Is the shoulder complex used as a lever when driving out hard while using a backswing? Does that even make sense?

I didn't want to muck up Squeeze's thread about arm circle speed with this question. I was getting really lost in that discussion and find myself questioning my thoughts on the reason's for driving out hard.

I thought that driving out hard while swinging back would initiate the levering of the shoulder joint and help provide arm speed so that at plant, you could bump up the arm speed/force being generated if your timing is correct. Especially since your arm has to travel quite a bit farther than your drive out. Give your arm a running start, if you will.

Sort of like when you were a kid and had your bike upside down and spin the wheel. If you time slapping the spinning wheel correctly, you can increase the speed of the spin. And if you use a stick (or screwdriver or whatever else you were playing with) it is even easier to increase the speed of the spinning wheel. Does something like this apply to the arm circle?

I get the driving the bus into a wall and such as regards plant and turning the spinning wheel into force.

In my mind, I am seeing arm speed as having an important role. I have ten more days before my daughter starts back up and I really want to help her understand the complete role of a hard drive out with a "backswing."

And if I'm lost, just say "hey, you're lost'" No hard feelings on my part.

 

[halskinner]

When you say 'driving forward hard', I have to interpret that as meaning pushing off the rubber, fast, strong and aggressively. Many pitchers will start their push off before the ball reaches the hip after being brought back. Doing that will mess your timing of EVERYTHING all up because, you can never get it exactly the same twice in a row.

When my students pitched with the double pump wind up. I always made sure the ball and the stride foot came forward of the rubber at exactly the same time and speed, FAST. You have to make sure the ball is just into the downswing past 12:00 at landing foot touichdown.

If the ball is any farther into the downswing than that, your stride is not as strong or aggressive as it should be for the best speed.

 

[BoardMember]

Abby......The glenohumeral joint is a pivot point or axis, not a lever..........

If you want to understand the physics better of how that pivot point creates angular acceleration.........Do this simple test.........

Get a stick.......and a hoop....Small open frisbee......Hula-Hoop....Etc..........Hold the stick in your hand.........Hang the hoop on the stick.........

Now......Using the motion of the stick........Get the hoop moving around the stick...........

The point where the stick contacts the hoop is the pivot point..........

PAY CLOSE ATTENTION to the direction you move the stick moves compared to the direction the hoop moves to accelerate the hoop circle........

What you'll find is that in order to accelerate the hoop.........The stick is moving in the opposite direction as the hoop........Feel the angular force and resistance in the stick as you do this........

Now try to move the stick in the same direction as the hoop.......I.E, as the hoop moves forward move the stick forward.........What happens?..........Collapse of angular momentum/acceleration........

This should tell you whether you should WAIT for the arm to move in front of the shoulder BEFORE the shoulder drives forward off the rubber.........

Quite simple really............Any thing else is an un-educated "guess" IMO...........

 

[abbygale]

That is what I am asking. I'm glad you got to what I was trying to ask.

I'm going to use the word "fling" with my daughter and I'm going to have her learn how to initiate/create it with a stick and a small hula hoop type thing so that she can better understand starting the arm circle. Hell, I'm going to do it myself after lunch just so that I can be better prepared.

Quick question. Is using the shoulder in its full movement range desirable?

 

[BoardMember]

Quick question. Is using the shoulder in its full movement range desirable?

This statement scares me a little........You don't "DO" anything with the shoulder except relax it........The humerus is ALLOWED to move within the shoulder joint as the arm is moved up and around the circle............

The shoulder joint or axis point is attached to the torso. The torso moves forward because the legs are driving the entire body forward from the rubber........Along with it......The axis point is propelled forward as the arm circle is moving rearward......That is like the force of the stick inside the hoop........

 

[MandM]

The torso moves forward because the legs are driving the entire body forward from the rubber........Along with it......The axis point is propelled forward as the arm circle is moving rearward......

I get this idea. My understanding is that as the arms reach out to first quarter position, that the stride leg should be at maximal extension. One of the problems my DD has had is getting to this position, as her arm circle is coming forward and comes past the hip (6 oclock) she is already starting to extend her stride leg, so she has been trying to correct this by trying to start her arm forward from the back swing as she starts her forward motion, which I guess is a bad idea (if that statement makes sense to anyone). Arghh. One step forward, two steps back Any suggestions?

 

[BoardMember]

I get this idea. My understanding is that as the arms reach out to first quarter position, that the stride leg should be at maximal extension. One of the problems my DD has had is getting to this position, as her arm circle is coming forward and comes past the hip (6 oclock) she is already starting to extend her stride leg, so she has been trying to correct this by trying to start her arm forward from the back swing as she starts her forward motion, which I guess is a bad idea (if that statement makes sense to anyone). Arghh. One step forward, two steps back Any suggestions?

Hold on a minute!!!........If you are saying her arm is BEHIND HER when she starts her forward motion........That's a GOOD thing!........

That means that the body has begun it's forward lean in preparation for a good PUSH while the arm is loading back.......And the ACTUAL PUSH BEGINS BEFORE THE ARM PASSES THE RUBBER........If the body is beginning it's forward lean in preparation to push........Then the axis point (shoulder) should be moving forward with that lean right?........And if the actual push happen with the arm behind the body.......Then timing the forward swing of the arm WITH THE ACTUAL PUSH FORWARD WITH THE LEG means that there IS overlap of that motion.........

OVERLAP IS WHAT IT'S ALL ABOUT!!!

 

[abbygale]

This statement scares me a little........You don't "DO" anything with the shoulder except relax it........The humerus is ALLOWED to move within the shoulder joint as the arm is moved up and around the circle............
......

I'm glad to hear that. I played around at lunch and if I really extended/reached forward with my arm, it was kind of painful.

On the plus side. I can make my arm do the stick in the hoop and feel it while doing the swingback. Now I want to understand how to keep accelerating it. Do I think about keeping the stick/shoulder moving ahead of the hoop/arm?

And when do I stop the stick and fling the hoop? As it translates to the pitching motion. I'm assuming I fling it with some I/R

Talk about teaching them from where they are at. You guy's should get a medal for helping me.

 

[BoardMember]

I'm glad to hear that. I played around at lunch and if I really extended/reached forward with my arm, it was kind of painful.

On the plus side. I can make my arm do the stick in the hoop and feel it while doing the swingback. Now I want to understand how to keep accelerating it. Do I think about keeping the stick/shoulder moving ahead of the hoop/arm?

And when do I stop the stick and fling the hoop? As it translates to the pitching motion. I'm assuming I fling it with some I/R

Talk about teaching them from where they are at. You guy's should get a medal for helping me.

Ok, so there are 2 points of "overlap".......In the beginning of the push from the rubber there is overlap.......The shoulder moving forward with the body as the arm is behind........Then, as the arm moves over the top and rearward, the shoulder is STILL moving forward until foot plant blocks the forward movement.........

If the timing is right........You don't have to DO anything........Except make sure the revolution in the arm circle is in the proper place at the proper time.........In the push and go delivery........There is only ONE overlap.......That is as the arm passes over the top........In the rocker arm delivery, there are two overlaps........One in the initial push, and the second over the top.........

Have you ever been on a "tilt-a-whirl" at a carnival?.........What happens every time the spinning carriage hits just the right spot of pivot force???........Then sometimes it goes for a bit without hitting that pivot force timing, and the thing just kinda sits there........

The thing about the tilt-a-whirl carriage is that it's timing to catch the pivot force is RANDOM........When it does happens, BOY do you know it!

Our arm circles and push off's are NOT random. They are precisely timed every time.........So we have a ability to adjust positions/timing within the circle we make to insure sure we hit the "pivot force" in the right place at the right time.......EVERY TIME......

 

[abbygale]

Thanks, I get the overlap on both sides now. Is the purpose the front side overlap to get the arm up to speed so that the back side overlap has more momentum to work with? Is it less strenuous on the body? Does it help provide for a bigger window to catch the backside timing in?

Is there a mechanical downside/trade-off to it?