Thanks for this timely thread as I’ve also wondered about working with a personal trainer on these issues. As a lot of you have said, tension seems to be my biggest impediment. I do a series of stretches after I play to relieve tension in the neck, shoulders and back. As others, I keep overall fitness with cycling, walking, yoga and diet. But I still battle arthritis all over that creates a lot of tension, so keeping my stance balanced is super important (I’m a stander). But if get sucked into a piece that requires a lot of focus on my right and left hands I too lose the ability to stay balanced and also put to much pressure on my right foot/leg. Oddly when I’m playing, everything feels fine. When I stop, that’s when the pain creeps back in.