It's not stated in this video but all of these problems are caused by bad posture/technique. I can't comment on the stretches and their efficacy because I have never studied physical therapy. However, as recovering injured pianist recently introduced to the Tauberman Technique, I can confidently say that pretty much every description this lady gives of piano playing is a classic example of a bad injury-causing technique. If you're getting tense or have pain anywhere after or while playing, there's a technical problem going on, IT IS NOT NORMAL. I had to learn that the hard way. If you can figure out with your teacher what the technical problems are (there's usually more than one), the problems will disappear (provided they are not serious and don't require therapy or surgery). Although it is still very good to stretch before and after playing as well as exercise adequately because those two things are always beneficial. If anybody's interested in the Tauberman Technique, there's a free documentary on the Golanski institute RU-vid Channel called "Choreography of the Hands."
This works really well for me. Easy, pretty quick to do and it feels good. Thank you. :):) By the way, it's also very effective for my computer keyboard, and taking the tension out of my hands and arms for golf!
