Pull-ups (better if you do wide-grip pull ups) are the best overall strength exercise you can do , even better than push-ups. Many meat heads at gyms don’t do the exercise because they can’t. (Fuck gyms, a complete waste of money.) Unfortunately, they are hard. You have to keep at it. Start with half-way pull-ups, letting yourself down as slow as you can. You’re still getting a great strength stretch, and it will get you closer, faster, to doing one…and then two…etc.