When I talk about strengthening the muscles I do not mean to produce more muscle power. I wonder if you are aware, that muscles which are too tense often are so because they are too weak, not because they are too strong.
Are you sure it's this way around? I'd say that the muscles are weak BECAUSE they spend so much time generically tensed. Rather than strengthening them, this kind of activity can atrophy them. In my opinion, exercise helps because it teaches you to let go of them- rather than keep locking them up in a rigid position. Sure, exercise can help to strengthen things- but it doesn't necessarily follow that it's an act of strengthening that has made the difference. It's perfectly logical to think that the exercise just trained you to let go of a tension that was impeding you and that this was the primary source of change.
To correct the wrist I had to make the forearm muscles stronger to be able to work and relax at will instead of just be cramped or completely unfunctional.
Does strengthening muscles make that happen? I don't personally believe so. I think it's more about the quality of how the hand is connecting to the piano. It's not a case of generically gaining strength and therefore being able to relax at will. The hand of a sumo wrestler can be poorly connected and hence dependent on many tensions. The hand of a hunger-striker can be very well connected and take the whole workload of support off the wrist (when coupled with equally low effort shoulder activity). In most cases, it's a matter of learning how to achieve more efficient balance. From there, some strength does tend to evolve through the actions involved, but I don't believe that generic strength makes it come about. I'd say it's much more likely that you learned how to let go of habitual tensions- which freed you up to perceive useful activities more easily.
To do so I needed to "find" these muscles, since I had absolutely no inside feeling whether they were cramped, relaxed or even where they were. So I needed exercises that had nothing to do with playing, but getting back this lost "feeling" of what is happening with the muscles.
This very much seems to confirm what I suggest in the previous paragraph. It's about perception- not strength. These are exactly the kind of exercises I include in my blog- those that train you to release the specific efforts that serve no pianistic function while training you to perceive those that are can be objectively proven as indispensable.
As you know the muscles involved are not necessarily at the pivot, so I assumed you would not misinterpret what I wrote about the wrist and muscle balance.
I wrote what I did, because it's very unusual for anyone to blame weak muscles for wrist issues- while actually referring to the muscles that connect the hands to the keys. If you'd immediately said that you were talking about insufficient quality of connection to the keyboard, I'd have seen what you mean. However, the fact that you were talking of "strength" made me assume you were looking at precisely that. I think what you are referring to as development "strength" is primarily a process of having learned to release muscles that were previously hampering you- not a case of improving due to added muscular strength. It's much more about what the brain asks the muscles to do than how strong they are. Bad alignments make you feel like you need more strength- but it's more about fine tuning muscular actions, so you involve the useful ones and eliminate the counterproductive ones.
Topic: stronger fingers