ShootingArts said:
The pendulum stroke with minimal elbow movement is effective. However the idea that it is physically a simple stroke to execute is a myth. Without considering the muscles used to create the stance, the pendulum stroke still relies on muscles in the neck, shoulder, back, side, upper arm, forearm, wrist, and fingers. It uses all of the muscles that any other stroke uses, it just uses some of them in different ways.
Are our muscles better suited to work together to maintain movement in a straight line or are they better suited to immobilize our upper arm and have free motion in our lower arm, movement actually created by the muscles in our upper arm? My contention is that we use coordinated movement of the complete arm constantly in our daily lives, we attempt to hold our upper arm stationary while in a somewhat awkward position while moving fluidly beneath it only when shooting pool.
Hu
I agree with this thought, and, more generally, I have problems with the whole argument that "simpler is better". At best, the idea that less moving parts means less can go wrong is a valid principle in, say, mechanical engineering or robotics, but the human body is nothing like a mechanical robot. It doesn't have joint motors, it has contracting muscles. And the way the brain communicates with the muscles is nothing like the way a robot communicates with its motors.
If the experienced instructors here and elsewhere claim that they have best success teaching the pendulum stroke, I believe that. But I don't find theoretical/scientific arguments in favor of the pendulum stroke pursuasive.
I also don't agree that what gets a beginner to C-speed quickest, or even what gets a C player to an A player quickest is necessarily the best way to perform the stroke. Maybe it is, but I don't think that there is enough evidence to draw that conclusion. Particularly given the fact that many of the world's top players do not have a pendulum stroke. In order to override this empirical evidence on theoretical grounds (e.g. the argument that the "best" method on paper is superior to the method which is actually used by the best players in the world), IMHO, you need a stronger theoretical argument then "simpler is better". Again, maybe most pros are indeed doing it wrong, but I'm certainly not going to believe that based on stick-figure diagrams and analogies between the human body and a mechanical pendulum.
For starters, counting the number of moving joints is an *extremely* poor way of judging the complexity of a human body motion, for obvious reasons (e.g., try closing just your ring finger rather than all four). Counting the number of muscles that contract is equally flawed.
Moreover, as quoted above, keeping your elbow fixed while your forearm moves is neither natural nor easy, since the acceleration of the forearm during the backswing induces a force which must be counterbalanced. Keeping the elbow still requires additional muscular effort which must be timed to coincide with these induced forces. The idea that "not moving" is "simple" is an illusion. If your upper arm was bolted in place, the argument that the pendulum is "simpler" would be more reasonable, but your arm is being kept still by intention and not by default, and in this sense, keeping the elbow fixed requires extra muscular effort which is peripheral to the general objective of stroking the cue. Maybe this extra effort is a good thing, but if so, it's not because "simpler is better".
There are many natural examples of useful auxiliary body movements--e.g. swinging your arms while walking. Walking robots don't generally have swinging arms, but that's because robot walking is very primitive, and robots have nothing comparable to the innate sense of balance and coordination of a human.
I have no idea what "correct" technique is. If I were to guess, I'd say probably some elbow drop is either beneficial or at least OK, and not worrying about whether the elbow drops is probably best, since I don't see any reason to avoid it. But I could easily be wrong, and more importantly, I think theoretical arguments along these lines should be met with some skepticism. I think there are a lot of good ideas here, both in favor and against the pendulum, but in the end, there's just not enough evidence to really draw a confident conclusion.
