Does anyone here practice standing up? I've noticed that I hunch over and I'm very tight and strained when I play. I'm trying to strech out and get comfortable while practicing but it's tough. Even when standing I can feel my left shoulder tensing up and I'm having difficulty keeping my thumb centered behind the fretboard in the correct position - I always stray and my fingers aren't always centered across the strings. It's tough getting comfortable and relaxed to practice. Anyone else have these issues?