I've been trying to pay more attention to my posture lately, as playing the piano underscores that my upper back slumps all the time when I'm not thinking about it and trying to sit straight while playing for an hour makes it hurt. I figure the push-ups should help strengthen my upper back muscles and help with that. I'll do the test for those tonight and see how many I can do at once - I got sidetracked by the squats last night. XD