There's a million ways to strengthen your wrist/forearm/shoulders so that you'll draw several hours straight without developing degenerative injuries. You can do it with free weights or bodyweight, doesn't matter. A simple one is angling your wrists to a 45 or 90 degree angle and letting them support your weight while you do bar hangs or pullups. Mobility exercises are also important.
https://www.youtube.com/watch?v=sYrIMdOBHkg>>3860679Not really, most of my art friends have had some form of RSI condition. I got tendinitis when I got serious about art and went into fundamentals grindmode. A couple people intuitively figure out good posture and ergonomics or happen upon them by chance.
