i'm with adam when he says;
QUOTE:
DON'T REPLACE YOGAX!!! P90X IS HARD!! STICK WITH IT!!
yoga is there for a reason, x stretch comes nowhere close to what yoga can do for you. talk to seasoned Yogi's, and they will tell you that Yoga X is pretty advanced as well. so for a beginner? this video is uber tough. my one complaint is that Tony does not provide enough modification for the moves. so here's a few tips from a class that i took:
for upward dog (which really isnt too bad), do cobra instead, until you build the stregth to keep your knees off the mat, and turtle head out of the shell.
for any of the warrior poses, if those are hard for you, put the back knee down. but make sure you're still getting that stretch in the back leg (meaning, dont look like you've just gone down on one knee to propose!).
for things like, right angle pose and triangle pose, get a yoga block. the yoga block allows you to do those same poses, but not have to go as deep. what some people do (and myself included), is use a push up bar, if you dont have a yoga block handy. and as Tony shows in the videos, you can always use your leg (shin) or foot.
all in all, dont feel like you have to follow the kids in the video move for move. modify where you need to and the progress will come. i was inflexible and falling all over when i first did it. but i kept at it a bam! i can now touch my nose to my knee (only on my right side tho...haha). just like many, who could barely do 1 pull up in the beginning, and are now pounding out 10+ at the end of the 90 days, you also will not be as flexible!
KEEP PUSHING PLAY and BRING IT!