There are a few away-from-the-horn exercises that brass players have developed over the years to augment practice, such as free buzzing, the P.E.T.E., and the pencil trick exercise. You might think of these exercises as being analogous to weight training for your chops. They are an effective way to strengthen specific embouchure muscles away from the horn in such a way that you don’t risk the injury that can come from excessive mouthpiece pressure. They are also strenuous, when done correctly, so they really work the muscles when done properly.
One of the oldest of these exercises is the the “pencil trick.” I’ve come across this in many different places, but the original source seems to be from Donald Reinhardt. His instructions are also fairly detailed and really seem to target the precise muscle groups needed when followed. Reinhardt wrote:
A standard, unsharpened wooden pencil is generally used for this routine. Form your saturated embouchure as if to buzz and place the tip of either end of the pencil between your compressed lips – NOT BETWEEN YOUR TEETH. While pointing the pencil in a forward, horizontal manner, strive to support it with only the “pinching power” of your lips. Do not become discouraged if the pencil falls to the floor. In practically all cases a great deal of perseverance is required. As soon as sufficient pinching power of the embouchure formation has been achieved, the prescribed drill will no longer present a problem. Initially, do not attempt the embouchure pencil support for more than a few seconds at a time – it is extremely strenuous. After each attempt has been completed, remove the pencil from between your lips, drop your jaw, open your mouth, exhale and relax. You will feel the results of your workout throughout the lower part of your facial area; this is correct. The amount of time consumed for each workout may be extended; however, it is vital that you accomplish this by degrees.
Donald S. Reinhardt, Encyclopedia of the Pivot System, Appendix 4-5.
One thing that most people seem to miss when trying this exercise out is that you should set the pencil between your lips while forming your lips (and jaw) as if you were buzzing or playing. If you bunch up your chin or set your jaw in a different position, you’re not targeting the muscles you want to be and the exercise itself is too easy. To the left I am forming my embouchure as if I’m getting ready to play. Note the position of my jaw. My chin is held taunt and my mouth corners are locked in place as if I was buzzing. Thoroughly wetting your lips will make them more slippery and further enhance the challenge of this exercise.
Once you have set your lips with buzzing firmness, try to maintain this embouchure formation while holding the pencil between the lips, taking care to not use your teeth to help support it. It’s alright if the pencil drops a bit less than horizontal, as long as you’re maintaining the proper embouchure formation while doing this.
Again, many players when first trying this routine out will disengage the chin from the jaw or hold their jaw in a position that is too different from how they buzz. This results in the muscles of the chin bunching up and holding the pencil and makes this exercise too easy to have any practical benefit. Take a look at my chin in the following photo and note the difference from the correct position in the photos above.
Since I have a beard, you can’t really get a good look at the characteristic “peach pit” look of my chin in the photo to the left, but you definitely want to avoid this look when both playing and doing the pencil trick exercise. I can hold the pencil like this for a long period of time with this incorrect formation, but it doesn’t target the muscles that I want to strengthen. Holding the pencil with the correct embouchure formation is a struggle. Actually playing with your chin disengaged from your jaw like this correlates with some problems.
For a different look, compare the look of my chin and jaw doing the pencil trick exercise from the side.
In closing, I’d like to reiterate that a little goes a long way with this exercise as it is quite strenuous. 30 seconds or so a day is probably enough, at least at first. If you’re really having trouble with it you can “cheat” a bit by holding the pencil with your hand a bit, but think of this sort of like spotting yourself while lifting weights. You want to do as much of the work as possible with the embouchure muscles and your goal is proper form over length of time holding the pencil out. Finally, it’s tempting for a lot of people to do this exercise in the car. I recommend against this for two main reasons. First, is distracting you from your driving (quit talking on the phone while you’re at it). Secondly, think about what would happen if the air bag went off while you had a pencil between your lips. For the short amount of time it takes to derive good benefit from this exercise it hardly seems worth the risk.