Do you know what kind of arch you have? Want to find out? Just dip your foot in water and step on a paper bag. Then look closely at your footprint.

If you're flat-footed or have a low arch, you'll see your entire footprint. If you have a high arch, you'll see a thin line between the ball and heel print. If you have a neutral or normal arch, your print will look like a half moon.

So what's your type? Whatever it is, make sure you use this information next time you go shopping for the perfect workout shoe. Different shoes support different arches -- so be sure to find the shoe that's just right for you.