I've heard that rubbing Preparation H on your abs is an effective final touch before a contest/photo shoot (it pulls out the water for ultimate definition).  I also understand that Prep H contains Witchhazel which is an astringent so it makes sense.

Anyone tried either one of these?

ya it draws water out of your skin similar to how that cutting gel crap works but what ive read and seems to make sense, after about 3-4 hours your body just puts the water back in the skin and can sometimes store more water in the skin than before you removed it. i would use it 1-2 hours before a comp, pics, or photoshoot.

It doesn't do the Ultimate job but Prep H helps tighten the skin. Its the stuff list as the actuve ingredient.
I have used it.

The main ingredient in Prep-H is Phenylephrine hcl 0.25%... It's a vasoconstricter(sp)..