I have to preface my reply with the admission that I hold no qualifications in physiology or bio-mechanics. I am a mathematician with a strong understanding of physics, but in this area I’m just a motivated self-directed learner. If I am dubious of Anton’s claims, it is in no effort to discredit his teaching or his obvious skills.
Elastic deformation is absolutely a real thing, and any object under elastic deformation does indeed store potential energy. Any muscle under contraction or stretch will store some potential energy which will tend to return that muscle to it’s neutral position.
The issue I have with this is that the energy stored by this proportional (almost linearly) to the stretch or compression applied. When a massive object (like our picking hand) is oscillating, the force required to drive the oscillation is roughly proportional to the amplitude and the square of the frequency. We don’t control the frequency of oscillation, that depends on tempo.
So, if we wish to minimize the force required, which is necessary for stamina, we must minimize the amplitude (size of the movement). At some point, we will simply not be able to develop enough force to move our hand far enough to produce an effective movement. The point is, the movements are small, meaning the stored potential energy is small, and the release of that potential energy is a small contribution to the work our muscles must do to drive an oscillator.
When Anton lets his wrist drop loosely into flexion to demonstrate the bounce, he is letting one muscle of an antagonistic group reach maximal stretch while the other reaches maximal compression. The bounce produced by the release of potential energy is small, and easily damped. In normal guitar playing our muscles don’t reach maximal stretch or compression.
I can’t claim this with any authority, but as Ph.D student I attended a talk by an applied mathematician who was interested in modelling muscle tissue as part of his research with a bio-mechanics group. I remember very clearly when he described his frustration in determining the elastic behavior of muscle tissue. Apparently, it’s extremely difficult to measure accurately and muscle isn’t perfectly elastic. I remember he said that there was a threshold for deformation below which muscle wasn’t elastic, and therefore didn’t store potential energy, and another threshold for deformation, beyond which the muscle was no longer elastic.
I would absolutely agree that we should at least attempt to create conditions which allow for maximal recuperation. However, my impression is that in guitar playing, the potential energy stored in elastic deformation of muscle tissue is very small, and very possibly the deformations caused by small movements could be below the lower threshold.
So, I’m dubious. However, it is certainly the case that it requires additional force to drive a damped oscillator. We can certainly create unwanted damping by introducing unnecessary muscle tension and by setting the “neutral” position of our oscillator away from our position of minimal muscular tension (hand at rest).
Whether the potential energy stored in deformation is significant or not (and it may not be), the conditions which would be required to maximize recuperation would be the same as those required to eliminate unwanted damping.
