Try stretching out a little before you start playing. You read my mind, Glissando. Every day, before the first time you play, do these:1. Stretch your arms straight over your head and grab one hand with the other. Keep your body straight, and bend with your torso to the left and to the right. You should feel the stretch in your triceps and under your shoulders (in the armpit area). Do that until those muscles feel warm and loose.2. Put your arms at your side and slowly pull your shoulders up toward your ears as far as you can. Sort of like a shrugging motion. Do that until the muscles feel warm.3. Do the same as #2, but when you get your shoulders as high as they go, roll them backward in a semi-circular motion back to your starting/resting place. Again, repeat until you feel warmed up.This shouldn't take more than a minute or two to do, and remember to breathe regularly while doing these stretches. You may also find that if you take regular breaks while practicing, it will help. I never practice for more than 20-30 minutes without getting up and walking around, going to the bathroom, getting something to drink, etc. for a few minutes.
Playing the piano is a physical exercise. Granted, it's low impact, but physical nonetheless. If you're an athlete, a runner for instance, you always stretch BEFORE you exert yourself.
You're right, though, everybody has to do what works for them, and sometimes it takes some trial and error to figure out what works. I'm a huge advocate of relaxtion as well, and I don't think stretching is the opposite of relaxation at all. In fact, I use my "pre-game" stretching as relaxation in itself. I find it calming. If you're tense while stretching, then you're doing wrong.
i've noticed lately that when i sit on the piano for about an hour, my right shour tends to tense up a bit. anybody know what i am doing wrong? and is there any way to fix this? thanks!