The use of the rest stroke has experienced much controversy. When used correctly, the rest stroke can extract a wonderful sound from a classical guitar. Without understanding how it does this, it is difficult to make the guitar sing in situations where it cannot be employed. In fact, because it can’t be used in every situation, some guitarists have banished this popular stroke totally, quite unjustifiably.
The rest stroke is, more often than not, taught in its incomplete form. What can truly bring the guitar to life is making use of the knowledge that all our muscles function with an action and a re-action (which in medical terms is known as “agonistic” and “antagonistic” functions). These are opposing forces which, when used in association with each other, give the performer greater control and greater speed. In daily life most of our activities automatically employ these opposing forces.
No stroke ends simply with the production of a note, just as in tennis the stroke does not terminate at the point of contact with the ball. The follow-through in tennis does not have its equivalent in “resting the finger against the adjacent string”. The equivalent of the tennis follow-through is the ability to use the restraining (the “antagonistic”) action of the finger, even as it touches or even slams into the next string. Returning to the tennis parallel, using the adjacent string as a way to stop the finger’s motion is like loosening the grip on the racket immediately upon contact with the ball!
When we train both functions––action and restraining––to be used in guitar playing, the rest stroke can be converted to its complete form. Not only will the sound be more eloquent, but this approach can be used in other strokes, including the production of harmonics, percussive effects, pizzicato playing, etc. While this is not a basic concept taught to guitarists, the really good musicians do in fact use it.