I generally do about 3 sets that specifically targets a muscle, but not necessarily isolates, I then rotate to try to hit all the muscle in that muscle process. For example with biceps I will do 3 straight bar curls, then 3 with an ez curl bar, then 3 hammer curls, then 3 reverse curls. By the end of that sequence I have started on the brachialis and then go into my forearm workout where I startout doing reverse wrist curls with my palms down, then hammer wrist curls, then wrist curls (all in sets of 3). By doing this I get a very even workout in my arms without overtraining any one point. Since I switched to this type of workout my injuries have been non-existant (I used to be very injury prone). Anyway I stick to that kind of training for all body parts, I'll try to post a whole weeks schedule when I have more time.