Well, I finally finished this stretch of the program and I am very pleased by the results. It took me a little longer than 90 days--vacation, being old, etc., slowed me down a bit. I'll spare you all the semi-naked before & after photos
but here are a few data points to show you my progress:
Start: 190 pounds, 17% bodyfat
End: 182 pounds, 12% bodyfat
Dropped almost 2" in my waist, gained 2" in my chest and an inch in each bicep. Added 4" to my vertical leap, tripled my max wall squat time, and I can now max out at 5x the number of pullups I did when I started. My resting heart rate went from 65 to 55, and my BP is now 115/65. As a runner my legs were always very muscular, so not much change there. I compared my exercise logs from week 1 to week 12, and I'm floored by the progress. Much stronger and more flexible in every category.
This program kicks ass.
In fact, I decided not to stop.
After taking the past 10 days to rest & recupe, I started Round 2 this morning! My goals this time are for 6-8% bodyfat, a 34" waist and much larger upper body muscle gains.
This is probably the best shape I've been in since college. Still have a ways to go to get to my ideal fitness level, but at 46, I am very happy with where I am.
I highly recommend both the exercise & nutritional components of P90X!