Friday, March 09, 2012

To Push

Here's how The Free Dictionary defines the verb "push":
push  (psh)
v. pushed, push·ing, push·es
1. To apply pressure against for the purpose of moving: push a shopping cart through the aisles of a market.
In tennis, "to push" is to simply put the ball in play with the goal of waiting for your opponent to miss. The term is a pejorative. Nobody wants to be called a pusher.

My question is, do we tennis coaches encourage "pushing" when we instruct a player to "get your weight into the shot"?

I think the answer is unequivocally yes. When a human pushes something, a shopping cart in the definition above, a door, a car, the human puts his or her weight into the task. The person exerts pressure by the arms and by body weight. So putting your weight into something is fundamental to pushing.

Swinging, on the other hand, which is what a tennis player should do in order to move the racquet quickly to hit a ball hard, does not involve "getting the weight into" the swing. A swing is a rotational movement (think hammer throw) where the swinger's weight is not necessarily, or even usually, moving in the direction person is swinging the object. In order to swing an object, force must be directed inward to keep the object from traveling away in a straight line. (see centripetal acceleration here)

So, pushing force is directed in the intended direction of movement. "Get your weight into the shot."

Swinging force is directed inward so an object can be swung in a circular path rather than along a line. So weight, if directed anywhere, is directed inward in a swing.

"Get your weight back" is a better instruction than "Get your weight into the shot" if you're swinging an object.

If you want to push something, then by all means get your weight into it.


Pulling rather than pushing said...

Do you achieve this swinging force by rather than pushing, pulling your weight away from the shot,ex.hitting FH with weight on outside(right foot for righties)and transfering away from shot into left foot and even having left foot going slightly back?

Pulling rather than pushing said...

Do you achieve this swinging force by rather than pushing, pulling your weight away from the shot,ex.hitting FH with weight on outside(right foot for righties)and transfering away from shot into left foot and even having left foot going slightly back?

Bob said...

I don't think it's as simple as pulling your weight one way or another. I defer to Brian Gordon on how to most efficiently generate racquet speed.

I think advice like "getting your weight into" shots misses the point of how to generate racquet (or club, bat, or ball speeds) and moves players more towards improper mechanics than toward proper mechanics.

That advice has been around for a long, long time though, so maybe it works for a lot of people.

Pulling rather than pushing said...

Yes, I agree that pulling your wt one way or another is not what generates racquet speed, I was just trying to understand push vs pull, linear vs angular(wrong in saying swinging force). From what I understand in
Gordon's site, its the proper use of the stretch shortening cycle that is the fulcrum of the B.E.S.T.forehand.I ordered the USPTA DVD to really understand the concepts behind a sound FH but I am unable to find anything from Gordon online .Does the video you have on youtube holding your elbow in and in front and hitting FH, is this enhancing the SSC? Thank you, Alexandra

Bob said...

The video of me with my elbow in front doesn't have anything to do with the stretch-shorten cycle. It's simply to demonstrate where the elbow should be at contact. Sometimes the elbow is bent and sometimes it's straight, but except for emergencies the elbow is in front of the plane of the body at contact. I see many poor players with the elbow alongside or behind their body at contact. That and staying sideways are the two biggest flaws I see. If you get your elbow out front and get your belly button roughly toward the target you are a long way toward hitting decent forehands.

To hit great forehands you need to generate a lot of racquet speed and hit the ball cleanly, usually with a lot of topspin. The generation of racquet speed is where Brian Gordon comes in. The stretch-shorten cycle is part of what Brain calls neuro-muscular optimization. You want to begin contracting your muscles when they are lengthening. That means starting to generate force with the legs, then hip rotation, then trunk rotation, then arm and hand rotation. That's the old kinetic chain you hear so much about. The reason the sequencing matters is that the prior rotations stretch the subsequent muscles prior to contraction. That's how you generate more force and more force means more acceleration.

Brian teaches players how to get this force and acceleration the most efficiently, using shorter swings instead of longer swings. If you apply force over longer time you can get the same acceleration, but in modern tennis you don't have time to apply the force for very long. So you have to do it efficiently to get racquet speed with compact swings.

Without going to Brian and getting measured and so forth, the best way to think of it is that you're throwing the racquet through the ball. Pushing and throwing are very different motions and most humans are familiar with both. Don't push. Throw.

Pulling rather than pushing said...

I'm really grateful to you, after reading your post I picked up a racquet and a tennis ball,as I throw underarm well, I by grabing both the grip of the racquet and the ball, pretented I was throwing the ball at another ball, and paid attention to the racquet movement.. the brain sure is a funny thing, I have brain maps for balls but not racquets (can't wait for that brain stuff I read in your blog to come into play :) I'm joking as I really enjoy the process of learning, so after a few times I did the same throwing motion just with the racquet and I felt I just want to try it on the court..Thank you