In this Training Tuesday video Kelios Bonetti MD PhD explains five training errors that cause injury and how to avoid them. It’s a little slow and English-only speakers will have to read the subtitles but there’s a really lot of good information here.
For example, when doing pull ups, don’t extend the elbows completely. Hanging with a straight arm can result in elbow tendonitis and other injuries. Instead, make sure the arm has at least a 10 to 15 degree bend at the bottom of the pull up.