Everybody knows the Army puts a lot of emphasis on pushups. While in training my pushups got great but my shoulders started to pop and hurt. When I got home I began focusing hard on my back to balance it out and the pain and popping have gone away. But, my rear delts aren't growing and my shoulders just look flat compared to the front. I'm unable to go to a real gym for the next few months, and my equipment is limited so I don't know how to target my rear delts. I have a Marcy WM980 machine I use, and I do some work with truck tires my combatives coach showed me, and body weight work. Anybody have any suggestions?