This is a very interesting topic in sports. Exercise is very important for our health. This also applies to pull-ups. And only a small percentage of people can do it. How can you do one arm pull up? Some information you can find on this site : https://raisetwice.com/improvement/one-arm-pull-up-the-... It's not easy to learn, but it's not very difficult either. Of course, you have to learn how to do a regular pull-up, then a super heavy pull-up, and finally a one-handed pull-up. It's great if you have a coach to show you how to do it, but you can also do it on your own. Hope this helps. Have a great day!