I kept much of my workout today the same in that I am trying to predominantly work chest, shoulders and triceps. However, I let my trainer tell me what we were doing. It provided a pleasant surprise because while lifting as I normally would for these muscle groups, we lessened the weight, but increased to tempo of the workout along with changing up the amount of repetitions. For example, on several of the exercises, I had to do 12 repetitions, have an 8 second break, do 8 repetitions, have another 8 seconds, do 6 repetitions, another break and do 4 repetitions. The other thing that we did was to do an exercise for 45 seconds and then move directly into another exercise without stopping. The pleasant surprise was the calorie burn. I don't know what he has planned for circuit day, but it should be interesting.