As much as they tout P90X as “muscle confusion” you do get into a rut of working the same muscle groups. It’g great that the rut isn’t too long or too deep but doing Chest and Back again yesterday for the first time in a long time reminded me of two things. First, the value of change. If you don’t change things regularly you will inevitably fall into a pattern by which both physically and psychologically you will become entranced and then lulled to sleep. The fact that you are sore AGAIN the first time you do a workout you haven’t done in a while speaks volumes to that. Second, the value of entertainment in fulfilling the time commitment. I have come across a few people who have claimed that they have saved a few minutes here and there by skipping bits and pieces of the workout or by (myself included) substituting weights or heavy resistance for some of the exercises. My advice would be if you want to substitute, take a day to do that but when you are faced with a P90X workout or and Insanity workout, submit to the process and do the whole thing. Saving 10 minutes off the workout isn’t doing you any favours in fact it will hurt you in the long run. 10 minutes a day on a program that requires a 6 day a week commitment (watch out here comes the math) is A FULL HOUR that you have skipped. Now I understand you are thinking that it’s only the warmup or only the cooldown but believe me if you aren’t present you aren’t’ getting the benefit but if you are there, you will get more of a boost to your overall fitness and attitude than you will ever realize. Each day that you skip part of the workout you devalue the process and thereby devalue yourself. My daughter is 4 months old now and time is at a premium however even I can’t truly make the excuse that 10 minutes is going to make a huge difference in her life but I can guarantee because I have been there, it will make a huge difference in mine. If you want to incorporate other stuff, do it prudently and make a day for it or allot a specific time for it, it will help you get the most out of your 90 day commitment and your daily workout sanctuary.
So Day 1 was fine, although I struggled with the rotation and the reduced body part count but  it was fun. The next morning I was sore but not too badly. It was a comforting reminder that I had once again found more muscle in need of work.