Pull-Up Technique

I've only recently started breathing correctly on pull-ups. I find it awkward because you're supposed to exhale as you begin the first rep. I also recently found out that when you're in the up position, you should pull your shoulders back and push your chest forward. For range of motion, your arms should be locked on the down position and your chest should touch the bar in the up position. Just getting your chin over the bar isn't good enough. I also recommend not using any momentum as used in kipping pull-ups.