I get it! :-)
The Zombie Combat Manual says that a typical strong endomorph with a little extra padding will do best against the magical/slow zombies. Basically the zombies never stop coming, so having the little extra energy reserve is a big plus. They aren't fast, so you just need to be able to keep moving. In the event of a hand to hand combat situation, again being bigger/stronger is better.
Now if we are talking WWZ type zombies (movie), well then we fatties are going down! But then I will turn into a super zombie and come for you RichieRich. ;-)