Karen Sullivan, an AFPA Certified Personal Trainer and Pilates instructor, calls treadmills "the most sound investment anyone can make for home equipment." She stresses that having a treadmill at home eliminates a battery of excuses. "We all know how to walk and for many it is all they can do in the beginning of the fitness battle. Rain, snow, even blistering heat are no longer an issue when you have a treadmill in your home."

When it comes to narrowing it down, however, how do you know what machine is the perfect one for you?

Consider Your Goals First

Will this machine be used for occasional walking or for running five miles a day? This is an important question, as it determines the quality and features you need to look for. If more than one person in the household is planning on using the machine, you need to also consider the stats of those users –If you weigh 100 pounds and your husband tops 200, a basic machine may not suit you both. "Not only are the goals important but the journey," says Sullivan. "If you are heavy and want to get ALL your weight off, then you need something that will #1 handle your present body weight and #2 last until you are at your goal weight."

Measure, Measure, Measure

Unless you live in a mansion, you need to consider storage space. More expensive models usually fold, so they can be hidden behind doors, inside a closet, or against a wall. Cheaper models, however, may not include this feature. If you're planning on converting your basement into a workout room, you may not need a folding machine, but if the only space you have to exercise is your living room, then this is a must. If you plan on storing the treadmill after every workout, you also need to make sure that it has wheels. However light it may seem at the store, you won't be motivated to struggle with it on a daily basis.

Consider also the space the machine occupies once it unfolds. If you need 84 inches for the machine to fit, and only have 84, this may not be enough. Remember that you need to be able to get on and off the machine, move your arms freely, and not feel claustrophobic every time you get on it.