So when I do chins, palms facing my face, my left wrist starts hurting and my left shoulder feels a bit off. The wrist usually gets me to drop a few reps before failure. Similar, but less intense, pain occurs when doing curls with a straight bar.
I assume I have some (internal?) shoulder rotational issues but figured I’d ask here first before scouring the web.
If your shoulder is excessively inwardly rotated that cause increased torque in your wrist. I have other issues that don’t permit me to do chins but if it were me I’d do chins and pull-ups on rings for a while and improve shoulder external rotation in the interim.
Remember that the lats are an internal rotator of the shoulder, so consider if it’s time to focus elsewhere on the back for a while to improve shoulder external rotation more rapidly. Revisit the movement after some time and see how it feels.
When you’re in that supinated position, big strong muscles that flex your forearm and inwardly rotate your shoulders are lined up to be twisting against smaller, weaker muscles that externally rotate your shoulders and extend your wrists and forearms.
So you maybe you can “Fire Up” the smaller muscles before the chins, by doing something like band pullaparts with an underhand grip, or a few reverse wrist curls with a dumbbell.
Or you can get really wild and start Training those little muscles with crazy moves like
Another external rotation one I like is the “No Money.” Sometimes I pull the band apart then make a curling motion, keeping the twisted out tension on the band. Or lifting my arms Up, in like an underhanded overhead press motion, while keeping the external rotation/pull apart tension, to practice.