Going off the rock climbing theme: getting better at bouldering (or any other style, really) requires strengthening the muscles in your fingers. It would really be handy to have some exercises linked here for improving those muscles' firepower.
I don't climb much these days (but I used to enjoy a spot of overhang crack climbing), but I've always been under the impression that there aren't muscles in the fingers. I just double-checked, and there are some muscles in the fingers... but it looks like they're only good for opening the hand. Are kids these days using some esoteric hand-splaying moves I don't know about, or do you mean the muscles in your forearms?
I was thinking of the finger muscles themselves--if you're trying to do a static move on a crimpy hold, finger strength really helps.
Those are tendons in fingers that respond to hypertrophy for climbing, or more specifically the tendon collagen, not muscles. But that's only one strength component of climbing, probably more so for bouldering specifically, but hand grip endurance and power also require forearm strength as well. I am not sure if that would be helpful for sitting in front of a computer.
I returned to climbing after a long hiatus, and my issues with discomfort and kinks in my back while sitting for long periods sorted themselves out in a couple weeks.