So I'm about 6'3" 175 lbs. I'm thin, and I wouldn't say my arms are "scrawny," but they leave something to be desired. I really don't work out a lot at all, but I've decided I'd at least like to work on my arms and chest. I've got a pair of 20 lb. dumbbells, and I've started doing 3 sets of ten curls and then 3 sets of ten kick backs for the triceps, and as many push-ups as I can do. This leaves me sore for a day or two, so I'll do it again as soon as I'm not sore, about three times a week. Is this going to make any difference, or am I kidding myself? If anyone has any suggestions, I'd really appreciate it. I don't know much about this at all. Thanks!