It is important to learn the basics about treadmills so that when you're comparing different treadmills, you'll know what you're looking at. All treadmills have the same basic components: a motor, frame, deck, belt, rollers, flywheel, and display console but not all treadmills are built with the same quality.

Motor:

The motor is what delivers power to the belt system of the treadmill. All home treadmills now are made using DC (Direct Current) motors. Treadmill motors are measured in horsepower and usually range anywhere between 1.5 and 3.0 horsepower. DC motors only operate at their full capacity when running at their top speeds. Larger motors allow for a higher user weight rating, have a higher top speed, reduce component fatigue and make for a more stable running experience. When looking at HP pay close attention to “peak horsepower” this label lists the maximum power not continuous power which is what’s important for running. Also beware of cheaper motors that are using high RPM’s to increase the listed HP. Faster RPM’s means the motor is spinning faster which will cause it to burn out quickly. Don’t consider any motor that comes with less than a ten-year warranty.

Frame:

Frames are made from either steel or aluminum. Steel frames feel more spring-like when your foot strikes the deck, and tend to lend themselves to a tighter, quieter treadmill. Aluminum frames are strong and last just as long as steel, but aluminum treadmills have a deadpan feel because aluminum treadmill manufactures use rivets to hold the frames together opposed to the uni-body steel-welded frame. Steel frames have been criticized for rusting but a properly coated steel frame in a residential application is unlikely to have that issue. However, make sure you are not purchasing a bolted steel frame treadmill; be sure to look for a welded frame.

Deck:

The deck is the part of the treadmill that you run on, directly under the moving belt. The deck will eventually wear out because of the friction between the moving belt and the deck surface. A thick deck will generally provide more support, cushioning and durability. Some decks are made from layers of laminated wood while others are constructed of synthetic materials, check the grade of the plywood. Most of the top treadmill manufacturers are using 3/4”-1” thick solid wood decks that are typically mounted on elastomer rubber grommets on top of the steel frame. Some decks are reversible, which will double the life of the deck.

Belt:

Most high-quality treadmills have a two-ply belt consisting of a black polyurethane top-layer and an under-layer made of a nylon-polyester weave. Look for an appropriate length and width for your size, if the belt is undersized you'll bang your feet on the machine or trip. The width will vary from about 16 inches to over 20 inches and lengths from around 45 inches to over 60 inches. Look for a diagonal cut seam as they have extra bonding area and create a stronger belt. Diagonal seams also pass over the rollers more gradually so the belt runs smoother and quieter.

When it comes to the weave of the belt material check for a tight weave. A tight, soft weave on the bottom will last longer. Also check the material for polyester or polyester blend. It is cheaper to use only nylon. However, nylon gives off a buzzing sound due to the increased friction of a cheap belt. Nylon will feel rough and it will eventually wear away the deck’s top coating and also cause the treadmill to run hot and shortening its life, you want to make sure the underside of the belt is smooth. Some top manufacturers such as Cybex also use covered belts to prevent dirt from getting into the treadmill, a common cause of service issues.

Roller:

Rollers are long tube-shaped parts that provide underlying support for the belt. There are two rollers, one on the front and one on the back of the machine. The belt wraps around the rollers, which allows the belt to revolve around the deck. Good treadmill rollers will help reduce the amount of wear and tear on the belt and motor. If the rollers are low quality the belt will constantly move away from being centered on the rollers and will require continuous adjustments. Look for a roller that is at least 2”-3” in diameter although be aware that bigger rollers are not necessarily better. High-end treadmill machines have several features like crowned rollers, rubber-coated front rollers or even auto-tracking computerized rollers.

Flywheel:

The flywheel in your treadmill helps to regulate the speed and consistency of the belt and helps keep the belt from moving when you step on it. The flywheel also helps the machine from overheating and wearing out quickly and prevents the treadmill from causing sudden jerky movements when you stop. Good quality flywheels typically can be found in treadmills that cost $1,000 or more. Inexpensive treadmills will have an unsteady, lurching motion, due to a poor quality flywheel.

Display Console

Don’t get over excited by the display console and forget about all the other important factors but use the console options to help meet your needs. Most importantly, the console buttons for changing speed and incline should be easy to read and reach with your fingers, and should respond quickly to selections.

Warranty:

Each treadmill has both an upper electronics package, called the console, and a lower motor control board which is the brain. Electronic problems such as faulty wiring or a fried circuit board in the console are some of the most common problems. The lower control board of the treadmill is typically the most serviced part. Look for at least a three-year warranty on your electronics. I would suggest looking for 1 year on parts & labor and 10-20 years on the frame and motor.

For example the Life Fitness T5 carries a lifetime warranty on frame and shock absorbers, 10 years on motor, 7 years on electrical and mechanical parts, and 1 year on labor, which is a great warranty. Comparably, the Vision T9600 carries a lifetime warranty on the frame and motor, 5 years electronics/parts and 2 years labor. If you’re looking for a quality treadmill, then it’s going to run you over $1000 so look for extended warranty programs from your retailer and protect your investment!