Yes, it's totally common, just do max for every set, that's what I used to do. Going up and coming down, with both hands, counts as one rep. Start at the bottom, go up, end at the bottom=1 rep. Hope I helped!
Hey chris, there are some things that i wanted to know about the shoulder up downs: 1) should I bent my elbows when doing the exercise?
2) does this exercise supose to be like a dynamic "lean forward" I know that you said the starting position is like a regular push up but you also said to put the weight on the shoulders.
3) do I need to shrug my shoulders (scapula) when raising the arm on do I need to stay in the protracted position all the time?