Foud out today that I'm pretty much 80% of the way there to doing a one armed chin up. Have been training pretty hard recently with sets of 25 most days and regular press ups/other weights in the gym but was very shocked when i tried. Never used to be able to move at all and can now lift myself up from about a 30 degree angle arm bend. i.e. not fully extended but not far off. Used to only be able to hold it at 90 degree s for a few seconds.