When you're looking to buy just one piece of gym equipment to use at home, two things will stand out to you: treadmills and elliptical training machines. They're practically the most popular exercise gear, coming close in second to the ever-popular dumbbells and weights. Both machines are known to be excellent tools for cardio workouts and because of their effectiveness, are considered useful for all regimens.

Elliptical training machines and treadmills are not created equal, however; just because they're both cardio workout equipment, doesn't mean they improve exactly the same things in the human body. These two pieces of equipment have entirely different functions, and you should look into these functions before making your decision to buy.

Treadmills, being older and thus having enjoyed a longer stint in the market, are a traditional favorite. The treadmill focuses on working out the lower half of your body, by simulating running and walking exercises indoors. This makes treadmills an excellent device to help you burn up unwanted calories. Treadmills provide a reasonably lighter impact so that your legs don't get as strained as they would be during regular outdoor runs or jogs. The less impact there is on your legs, the less chances there are of your leg muscles bulking up, like competitive runners' legs do. Electric treadmills are especially useful for lessening the friction between your feet and the running belt. You can set speeds so that you can walk or run at different paces, depending on what's comfortable and recommended for you.

But while newer in the market, elliptical machines deserve a second look. They not only exercise the lower body and pump up the heart like treadmills do; they also give your upper body a good aerobic workout. Elliptical machines have different models and makes, but for the most part they resemble cycling machines where you don't actually get to sit down while you cycle – in fact, you do your pedaling standing up, on flat vertical pedals! If the treadmill lessens the friction between your feet and the running area, the elliptical trainer virtually removes it, providing more fluidity of movement but at the same time inviting the body to use less force.

If you want a stronger and more solidly "built" lower body, you should definitely get the treadmill. The treadmill is great for people who want to build up their stamina while toning their leg muscles. It's especially useful for people who need to train for marathons or walkathons. The elliptical training machine, being a lower-impact device, doesn't bulk up your limbs as much, but does provide a full-body workout. It distributes the results of the exercise equally throughout both the upper and lower parts of the body.