Ok.

Here is how it goes.
1. There are several levels to PPI. Piano playing at its most basic is movement and co-ordination. It is not intellectual work. So people above (and Chang) concentrate a lot on the “brain” – and by that we immediately assume it is the intellectual brain. But remember that we have several “brains”.
For instance, when you eat, one of your brains (who definitely has a degree in biochemistry) regulates to the minutest amount how much acid must go in your stomach; how how much of which hormones must go into your blood at any given moment. It determines how your heart will beat. How much your pupils will dilate in accordance to the amount of environmental light. And so on and so forth.
Don’t you think this is an amazing “brain”? Even though our “intellectual brain” may have no knowledge of biochemistry, physics or maths, somehow our “instinctive brain” (that is what I have decided to call it) knows about all those subjects. In fact it knows far more that what all our scientists have discovered so far, since all the time we surprise scientists by doing things that according to science at a given moment should be impossible (acupuncture comes to mind – until the 60s was considered superstition at best and charlatanism at worst. Now it is more or less accepted and still not understood). However, for piano playing the “instinctive brain” is of little concern (unless it is not working properly, in which case you die

).
2. Level 1: purely physical. Now I am talking about the sensations and movements. Yes, there is a “brain” that deals with this. And it is not the “brain” in your head. I call it the “motion brain”. It makes sure we move correctly. That we perceive sensorial data through the sense organs and that we act on these sensations. Many animals have only instinctive and motion brains. And they function perfectly well within these limitations. This is the brain that controls typing, driving a car, physical exercise and of course piano playing.
Many people get confused with the instinctive and the motion brain. There is no need. They may seem similar on the surface , but there is a huge difference: The instinctive brain learns nothing. It is born knowing everything it needs to know (think about it: If you had to learn how to make your heart beat you would be dead before the lesson even started). The motion brain on the other hand must learn everything from scratch. It knows nothing. This may surprise some of you, but we have to learn how to see, how to hear, how to taste, how to smell and so on. But because we learned this stuff at a very very young age we get deluded into thinking that this stuff is instinctive, that we were born knowing it. [Here is a side thought: This means that prodigies are not born. They have to learn the stuff]. The motion brain also has a specific way of learning, it will not learn in any other way. It learns only by imitation. Did you hear this piano teachers? It is pretty useless as far as learning to
play the piano goes, to have deep intellectual discussions about the meaning of music, or to endlessly analyse the harmony of a piece. This is certainly fun and will add to your
understanding of the piece and it certainly
must be done, but it will not further your progress in playing one single micron. For a student to learn to play the piano, s/he must have a model to imitate.
But I am digressing.
Back to PPI.
Physically PPI works in a very straight forward manner. Consider bodybuilding. You will not build muscles while exercising. You will build muscle when you are resting. The reason for this is simple. When you are lifting weights, you are not simply exercising the muscles. You are ripping them apart (just look at the faces of the guys). It is painful. However, the muscle gets rebuild in time (it takes 36 hours), and when it gets rebuilt, it gets bigger and hence stronger. So a basic principle to grow muscle is “no pain, no gain”. No pain means that you are not ripping the muscle. And if you are not ripping the muscle, you will not rebuild it.
If you look at pictures of Mr Universe in the 50s they are skinny fellows compared to today’ guys. Part of the reason for this increase in size is the use of anabolic steroids. But part of the reason is that in the 50s sports physiology was not at all well understood. So people were going to the gym every day and they would exercise the same muscles everyday. They were ripping the muscles all right, but they were not giving time for the healing and rebuilding process to happen. They would get injured.
Then it was discovered that this process took 36 hours. So now, a body builder still trains everyday, but he has a rigid rota of muscles to be exercised, so that there is always a 36 hour period between sessions devoted to specific groups of muscles. So he might do legs on Monday morning, but then he will rest the leg muscles until Tuesday afternoon. Meanwhile he will do arms on Monday afternoon, and only go back to arms again on Wednesday morning. Once body builders started to do that in the early 60s, the results were astounding.
So, from a muscle point of view, PPI simply means that you do not get strong while you are exercising, but while you are resting, since it is when you rest that the muscles get rebuilt (=stronger and bigger).
There is always a smart alec who concludes from the above that in order to get big muscles you should therefore rest and never exercise. No, the exercise is very important, because if your muscles do not get ripped, there is no reason for them to get rebuilt, duh!
But this also shows how important it is to have the correct procedure. Without this information (muscle must be ripped to grow – it takes 36 hours to repair ripped muscle), you will never stand a chance of progress.
So it is with piano practice. The guys who are progressing (both in body building or in piano) either know this stuff, or are following the correct procedure by pure chance (which might be a much better explanation why there are so few good pianists – instead of the usual one that you must be a prodigy).
Now, piano is done with muscles. But most of the movements in piano playing are not movements that we normally do in daily life. Muscle that is not used atrophies. Most adults who start playing the piano from scratch have atrophied muscles (for the necessary movements). Hence the beginner’s clumsiness. As with any physical exercise, muscle will grow with repeated use. So in the beginning repetition of the basic, important movements is essential.
It takes 3 – 6 months for muscle to grow. So this is the worst period. A teacher can be really helpful at this period if s/he knows which movements should be repeated, and if s/he can ensure that daily repetition of the
correct movements is enforced. On the other hand a teacher who does not know about this stuff can add years to a student learning and ensure that the student will never be able to progress. So this is the muscle story: PPI is simply the rest period in between training sessions when muscle ripped by the exercise is allowed to repair itself and grow (36 hours).
Now do not get the wrong idea here. Although I have used bodybuilding as an example (because it is extreme), muscle building in piano playing is not this extreme ever. Think of a baby. Why does it take a baby one year to start walking? A good percentage of this time is simply growing the leg muscles (and other) that will allow the baby to stand up. Even if the baby “knew” how to walk, it would still take 6 months for the necessary muscles to grow. You can see that in people who have been in bed for a prolonged period of time (e.g. coma patients that wake up after 4 – 5 years). They know how to walk, but they cannot, because their muscles have wasted away from lack of use. However they will recover quickly, since they know how to walk and their attempts to do so will rebuild the muscles much faster than a baby who does not know how to walk and therefore wastes many movements “experimenting”.
Likewise in piano playing, we need first to build up the necessary muscles – not to the point of a body builder, but to the point that will allow a baby to walk. And just like walking is all the exercise a baby needs to develop the necessary muscles for walking, playing the piano is all the exercise one needs to play the piano.
But to start with you will not have the muscles, so it will take 3 – 6 months. During this stage the main PPI at work is the 36 hour period for ripped muscle to repair itself.
The practical consequence: beginners must have a 36 hour period in between practising the same movement. Please understand this clearly: It does not mean that you should space your practise 36 hours. You must still practise everyday (just like a body builder) but you must have a rota: B major scale on Monday morning. Repeat only on Tuesday afternoon. Chord practice on Monday afternoon. Repeat only on Wednesday morning. Practise piece on Tuesday morning, repeat again only on Wednesday afternoon. You get the idea. The student does not have a clue about all this, and I strongly suggest that the teacher should not spend too much time explaining it. What the teacher must do is to spend as much time as needed to create a schedule for the student and make sure they stick to it. This is the greatest advantage of having a parent who is a piano teacher (assuming they know this stuff): they will ensure that their child sticks to this sort of program, and if they do, in five years time you have a “prodigy”.
Once muscle is built, it will only increase and get stronger if you keep ripping it. Otherwise it will stay at its level for as long as you keep it to the same physical demands. This means that after 3 – 6 months, you do not need to worry about the 36 hour period anymore. The muscle is now adequate for the work required of it.
[continues on the next post]