Ronaldo...
No matter what the munchkins are going to have WAY more energy then you

Great suggestion by SexyScribe, as well. This would be a good time for you to start relying or working on buidling a network of support.
Try calling up a friend who's got kids (or even better...doesn't! more hands...heheh) and set up a play date for the little ones. That way they're more apt to occupy themselves and you can get some adult time in to balance your day a bit.
'Nother suggestion -- you might want to find an activity you guys can do on the weekend together -- like swimming, a martial art, basically anything that's gonna expend their energy so that by the time you get home they're both ready to zone out and you might get a bit of quiet time
Good luck with the new routine...soon enough they'll be pretty darn autonomous, wanting to hang out with their friends, and you might find yourself missing this a bit
