I should probably state my stats/background:
191 pound (as of today)
Fitness level: I played basketball and soccer my whole life (on average 3 times a week). I've never before did a serious workout program similar to P90X. First time around was really tough. Second time around is easier because I know the routines, but it might be time to increase some of the weights. Right now, I do most of the exercises with 20 pound dumbbells.
I started playing tennis about 3 years ago. I never played in my life before. Right now I'm a solid 3.5 (maybe even a 4.0 player). I play about 4 times a week in the summer.