OK, let's be honest, not everyone can even do a full strict pull-up, that means arms straight at the bottom and just pull up using only your arm and back strength and no body language or kipping to get to the top. But if you have been practicing and you can do 15 or 20 strict pull-ups then maybe it's time to add some weight and really get strong in the back!
So that's exactly what I'm doing now! I've been adding some weight to my pull-ups every so often, sometimes at my CrossFit Class I will ad 25 pounds as long as we don't have to do too many ;) And at home I have been periodically loading up with my 47.5 pound dumbbell and seeing how many wide and narrow pull-ups I can do in a row. When I started I was only able to do about 3 wide and 5 narrow back to back pull-ups, over a relatively short period of time I am now up to about 16 total back to back pull-ups, so double!
By the HD Video Camera Glasses are made by Pivothead!