We're always told "If the shoe fits, wear it." Sure, I suppose if one were Cinderella and found oneself staring down at Prince Charming holding a shimmering, glass slipper--a shoe representing complete financial stability, a lavish palace and regal status--then yes, by all means put on the shoe. And hurry. But if we're discussing actual footwear here, especially athletic footwear, there are many of other things to consider before buying a shoe to fit with your fitness goals and genre of exercise. Cinderella would have gotten a headache confronting the abundance of options in athletic footwear today.

Pardon my copyright infringement, but despite its overwhelming nature, if you really know what to look for, the process of finding the right athletic shoe can become as simple as "bippity, boppity, boo!"

First of all, to wear the shoe in the first place it has to fit. Ask a salesperson at the store for help with fitting.

If your toe feels pinched while you're trying it on imagine the agony you're going to feel once you start cross-training in those kicks.

Apart from size, there are a lot of things that can differ from foot to foot which require additional attention in footwear. For instance, if you have flat feet, you need a shoe with more support in the arch.

Likewise if the arches of your feet are very high, you will require additional padding.

You may not even realize you possess these differing bipedal traits until a salesperson tells you, so it's important to ask for help.

Remember you're the one who has to walk a mile (or 10) in these shoes, not someone else. And ladies, don't even think about buying a size or two too small so you can feel "feminine" and "dainty."

Paris Hilton is a size 11. I'm a size 10. Get over it, your feet are big-- buy your size --your foot will thank you in the long run.

Speaking of long runs, purpose is the second quintessential question to ponder when buying an athletic shoe.

For example, a competitive track & field cleat serves a different purpose than a running shoe, despite their shared goal of running faster.

Traditional running shoes, good for jogging through the woods or around a city block, should stress cushioning over stability.

This is because running consists of propelling forward with out a lot of lateral movement.

The faster or more often you run, the more times the balls and heels of your feet will be slamming onto the hard ground. Therefore more padding between you and a surface will help to propel you forward and avoid injury.

However running is not a synonym for all athletic activity. I find a great example in the very popular Nike Shox, which very wrongly litter the wooden floors of my aerobics classes.

I want to make sure you are all listening because I am only going to say this once: Nike Shox are running shoes. They are sold and marketed as running shoes.

I understand that they have cute, little, neon springs in the see-through heels, but they have no place in an aerobics class, or on a basketball court, or anywhere where you aren't running for that matter.

Activities that require a lot of lateral (side-to-side) movement such as step and hi-lo aerobics, kickboxing, basketball, tennis, indoor soccer (basically everything but running) require a shoe with more support.

This usually means a heavier, more durable shoe with ankle support.

Technology has advanced in athletic footwear to the point where shoes are being specifically made for each sport so just follow the signs in the shoe store.

I know you're thinking: "I wish there was just one magical shoe that I could buy for all my fitness needs."

If athletically you're a jack of all trades than consider buying a cross trainer to suffice all your exercise needs. Cross trainers are lightweight and sturdy with sufficient support and cushioning. And they come in every shape and size, except for glass. Sorry, Cinderella.