WOW:) Working on my back looking like this! Do you want to be able to do a pull up? YOU CAN DO IT!!! The way to start building strength is doing lat pulls, lots of them. Or, if your gym has an assisted pull up machine, you can use that. Start doing 3-4 sets of 20 lat pulls at a weight that you can do 20 good reps, do 2 times a week! Every week add a little weight. Then jump on that pull up bar and do it! Start with one rep, you can even swing to start off with, then go for more and more!