Last updated on 23-Jan-2011 11:47:57 PM
In answer to an earlier question of mine, you said that 70% of spin from a serve comes from the wrist and 30% from the arm.
That got me thinking about other shots...namely the forehand and backhand loop. I know giving precise percentages to these things is meaningless but roughly speaking, how would you break up where spin is generated in these strokes?
Elbow (i.e. speed with which you close the angle of the elbow as you make contact with the ball) A %
Shoulders (i.e. basically speed with which you move the whole arm up over the ball) B%
Waist (i.e. speed with which you turn your torso through the shot) C%
Wrist (i.e. the breaking of the wrist as you make contact with the ball) D%
Forearm/Elbow (i.e. the speed with which the forearm moves from the elbow join) E%
Shoulder (i.e. the speed with which the whole arm moves from the shoulder) F%
An interesting question as always.
I think we need to think about what generates spin. It is the brushing contact and the speed of the contact. So for the serve the wrist is moving fastest.
For the forehand topspin I think the forearm is probably moving the fastest with a little help from the wrist. This is because the wrist is moving more in a sideways direction to generate the spin and doesn't have as full a range of movement as for the serve. The backhand topspin is also interesting. It probably follows the forehand topspin model closely.
The shoulder and waist and alos upper arm all add to the speed that you are able to move the bat. They will all have their part in generating more speed of contact.
Table Tennis strokes are a summation of forces. As you said it is difficult to put percentages on it but here is my feeling.
Forehand and Backhand topspin Wrist 30%, Forearm 50%, Waist & shoulders 20%. These are just feelings and certainly not backed up by any data. Maybe someone out there has some data they can share.