Who said Hanon isn't music by the way? Shostakovich even put his excercises in one of his piano concertos, to get his son practice Hanon!
Well, what do ya say bout that, bernie? 
I have two things to say. One I have already said above, but I will repeat it:
Finally do you really want to play Hanon? Then get yourself the Hal Leonard edition (Student piano library) which comes with a CD of orchestral accompaniments so that you can play Hanon with an orchestra! ( I kid you not )The second thing I have to say concerns the matter of warm-up.
The basics are here, so I will not repeat myself:
https://pianoforum.net/smf/index.php/topic,2457.msg21252.html#msg21252But I will add a bit more to it.
Once upon a time I went to a karate club, and when sparring time came, to my mild surprise everyone started to stretch and jump on the spot. Since I looked somewhat puzzled, someone offered an explanation: “we must warm-up and stretch so that if we do a high kick or other extreme move, we will not get inured”. I said: “Er… first, have we not warmed up at the start of the session? And, supposing you are attacked in a Pub, are you going to tell your attacker: Wait a second, I need to warm up and stretch so that I can defend myself without getting injured?”
So, you see, there is something wrong with this whole idea of warmup. At the basis of it is ignorance of the physiological processes involved. At the top of it there is psychological comfort that comes from years of conditioning. “If all lemmings are jumping of a cliff, this cannot possible be wrong! There is a huge historical precedence for it!”
So, let us sort it out. My martial arts colleague, was correct: warmup and stretching are very important to avoid injury. But he got it all wrong in terms of how and when and what to do. And he never addressed the real problem which was: What are you going to do in a situation where no warmup is possible?
Of course there is a perfectly good answer. And here it is in a summarised way (if you want the full details, I suggest you read Thomas Kurz “Science of Sports training” or any other good reference in sports physiology).
The secret to be able to do high kicks without warmup and previous stretching is simple. When you wake up, first thing in the morning, do some leg swings. The way to do those is very specific: you must not do them too fast and using momentum to lift the legs (the so called ballistic movement). Rather, do them slowly and with control, that is, the muscles in the leg are lifting the legs. It is very important that you watch out for any signs of fatigue, since you cannot attain maximum flexibility if your muscles are tired (it is the opposite principle of achieving strength – if you want muscle strength, you must workout through fatigue). Isn’t this interesting? You can do the same movement/exercise (leg swings), and yet, depending of your final goal (flexibility or strength) you must do it in a completely different way. Do it the wrong way and you will be defeating your purpose. Could that have any application to piano practice? Hmmmm… I wonder if all those hours of mindless repetition of technical exercises were wasted…
But I digress.
Back to the leg swings. So you are swinging your legs, slowly and with control, and they will achieve a maximum range. Now you have two options here: you may stop to swing your legs when you achieved your maximum range and it is clear that you will not get anything more that day. Or you can keep pressing on until your muscles are burning, and you will notice that your legs are not swinging as high anymore.
This is what sports physiologists found out: Somehow, the brain stores the last figures for maximum flexibility, and during the remainder of the day, you will always be able to swing your legs (or kick) to that maximum – without any need for further warm-up stretching.
So. You swing your legs. You got to the maximum you are going to achieve that day. Then
stop. That maximum figure will be with you throughout the day.
If you continue swinging so that your muscles tire, your range will decrease. When you finally stop, it is this less then best range that will be stored in your brain, and that will be the limit of your kicking range for that day – []even if you warmup/stretch later on [/i]. In fact, your ability to stretch later in the day will be limited by your leg swinging in the morning.
Moreover, if you do leg swings in a ballistic way (using momentum, throwing the legs violently in the air, aiming your thigh to hit your chest), you will notice that the muscles at the back of the leg will actually tense (the brain thinks “Oh no, he is going to throw that leg to the moon! I must stop it! I better tense the hamstrings!). So the way to do leg swings with a view to increase flexibility is not only slowly and with as little momentum as you can get away with, but stretch your arm in front, so that the arm presents a clear obstacle the leg can hit (start with the arm slow and raise it as your flexibility increases). The arm in front makes the brain relax: now he knows that the leg will not go all the way to the moon, since the arm is there to stop it. As a consequence you do not get a sudden tension of the muscles – which is the real cause of sprains and injuries.
So here are some situations.
1.You wake up. You do nothing. Your leg muscles will be shortened after a night’s sleep. They will remain shortened during the day. You go to training later in the evening, and you feel really stiff. No matter how much you stretch and warmup, you can never quite do what some people ion the class are doing. And you have been training for years! What are you doing wrong? These guys who can do it, keep giving you tips (“do this stretch”, “no pain no gain”, “just keep at it”, “you must practice harder and longer”). You wonder if you have any talent at all.
2. You wake up. You do leg swings with great energy, throwing your legs in the air and letting momentum carry them over. You can feel the muscles tensing, but you carry on nonetheless. Soon you are dead tired, and you can hardly lift your legs. So you stop. Later in the evening you go training, and you are even more stiff than the guy at no. 1. But you are developping some impressively bulging thighs. Until of course, the morning when something snaps and really hurts, and you must to physiotherapy and stop training for the next two years.
3. You wake up. You swing your legs slowly, carefully and under muscle control (not ballistically). You give your leg an obstacle to stop its ascension – may be your arm, maybe a punch bag, maybe a frame, so that the obstacle – rather than the leg muscles you want to stretch – stops your leg form going up forever. You keep swinging up to a point where you realise you will not be able to go higher, or to the point where you start to feel tired and to get diminishing returns. You go about your business during the rest of the day. In the evening, as you warmup and stretch in your training session, you can easily and without any effort reach the ranges you reached in the morning, and perhaps even go a bit further.
Guys 1 and 2 are impressed. They ask your advice. Now two things may happen:
a. You actually know what you are doing. You have studied the subject, you have experimented
scientifically (which means that you must have a control, that you note down and somehow quantify your results, and if necessary you even do a statistical analysis) with different approaches. If this is the case, you will be able to advise and help guys 1 and 2.
b. You have no clue. You just do this morning routine the way you do it, either because someone who knew about it told you about it (may be your father was a sports physiologist), or because you just stumbled on it by chance. So when you advise guys 1 and 2 chances are that your advice will have nothing to do with what you
actually do, but rather with
what you think and believe you do. And because you are clearly successful at what you do, everyone will be convinced that
what you say you do is actually the correct thing. The difference, of course is that such advice never results in improvement in any consistent way (sometimes it works, sometimes it does not), while the advice from someone who truly knows the ropes always has staggering effects.
Now I have been talking about leg swings, but of course the same applies to every part of the human body: It is what you do first thing in the morning that sets the range for the whole day.
Now, how does that apply to piano playing? Mostly it does not. There are several useful analogies you can draw here, but the fact of the matter is that piano playing rarely if ever has the equivalent of a high kick in its range of movements (if you can hardly span a seventh it is doubtful if stretching exercises are really going to change this too much – you may need to stick to a repertory that avoids huge hand spans).
Moreover, everything I said so far is not to be done on the piano, but away from it. I have a routine for flexibility of fingers and wrists that makes sure that my piano ranges are optimal, but I do not do those for piano – I do those for aikido. It just happens that they benefit the piano playing as well.
Now comes another interesting aspect of stretching. Few people seem to be aware that there are three distinct sorts of flexibility: dynamic, static and passive.
Dynamic flexibility is the one you need to swing your legs: movement is involved.
Passive flexibility, is yoga-like. If you just sit on the floor with open legs, you will slowly relax the muscles and you will be able to stretch further. No movement is really involved here: you simply hold a posture for a period of time (minimum: 2 minutes).
Static flexibility is of a different sort altogether. It is the sort of flexibility required in some dance forms, where you lift your leg and hold it up there. Not only the muscles in the back of your leg must be stretched to the limit, as the muscles in front are required to do a strength tour-de-force to keep your leg up there.
The differentiation is important, because training in one sort of flexibility does not guarantee improvements in the others. In particular, passive flexibility is counter to dynamic flexibility. If you spend some time doing passive stretches (yoga like), this actually interferes negatively with your motor co-ordination. Just watch a yoga class and observe the people at the end: they can barely walk.
Yet, 99% of martial art classes I attended, instructors were completely ignorant of these simple facts. They would always start by warming up with some silly movement like star jumps, and then do yoga-like passive stretching. As a consequence no one had motor co-ordination to do the next bit of the class (usually basic movements) correctly. Instead they should be doing dynamic stretching
as a warm up. Dynamic stretching (moving a limb to the limits of its range with control and slowly) is ideal as a warm up and sets up all the motor co-ordination centres.
So if you are going to do finger stretches and wrist stretches before your piano practice, make sure the stretches are dynamic, not passive. And make sure that once you achieve the maximum range, or you start to feel tired, you immediately stop.
The astute readers amongst you will see many connections here with things like PPI and the like.
Best wishes,
Bernhard.