Fortunately most prominent treadmill makers are manufacturing treadmills with good frames. However, there are some treadmill frame quality considerations when researching your treadmill purchase.

Frame materials

Frames are made with steel and aluminum. Most are steel.

Is steel better than aluminum? Vice versa?

Neither is unnecessarily better than the other. Aluminum is considered lighter than steel, but it's not always the case.

When assessing steel vs. aluminum strength, there are two aspects:

  • Strength: How much load the material can handle.
  • Stiffness: How much the material bends with a certain amount of load.

Aluminum will generally bend more under loads, but that does not mean it's stronger or better as a frame.

In fact, you do not want your frame to bend.

What type of treadmill frame material do I prefer?

Steel with a proper coating to prevent rust. I say this with cost in mind. In a perfect world, I've got a top of the line aluminum frame, but that is extremely costly.

Frame construction

Frames are generally assembled by bolting or welds.

Again, neither one is necessarily better. Some bolting techniques, like those used on aircraft are very strong and durable. The bolting technique used on some treadmills is called “locking.”

Welding, although the predominant treadmill frame construction method, is not always stronger. Cheap or poorly done welds can result in a weaker treadmill frame. That said, for the cost, you'll probably get a better deal on a welded frame. I say this because most treadmill frames are welded. That's why getting a treadmill with a lifetime warranty and high maximum user weight is a decent way to assess a treadmill's quality (see below).

If possible, get a treadmill frame warranty that includes the welds.

What costs more: steel or aluminum frame treadmills?

Typically, aluminum frame treadmills cost more than steel-framed treadmills.

So, how do you know if a treadmill frame is any good?

The information above might be interesting, but it unfortunately does not give a clear answer as to whether a steel frame is better than an aluminum frame. That's because there's no hard and fast rule.

Even if you try some treadmills, you will not know either the frame is durable because you will not have used it long. The only way you know for sure is buying it and using it until it does not work … and it's potential breakdown may not be related to the frame.

The quick and easy frame assessment

Without being an alloy expert or using every treadmill in your price range, the two best criteria for judging a treadmill frame are:

  • Frame warranty; and
  • Maximum user weight.

Treadmill frame warranty

If at all possible, get a treadmill with a lifetime frame warranty. More and more treadmills, even at the lower price range ($ 850 and up) are offering lifetime frame warranties.

Maximum user weight

The most common maximum user weight of treadmills is 300 pounds. However, if you're going to be a demanding user, then look for a frame with a 350 pound or higher maximum user weight.

What about the weight of the treadmill?

This provides some guidance. Generally the heavier treadmills are of better quality, but not always. That said, I'd look at treadmill weight as well as a third factor when assessing the durability and performance of a treadmill frame.

What about folding treadmills? Do folding treadmills have weaker frames?

There may be instances where a folding treadmill's design compromises frame strength and durability, but I would not buy a folding treadmill on this basis. Again, look to the frame warranty, maximum user weight, and weight of the treadmill to assess the frame.

How important is treadmill frame strength and durability?

Fairly important. You want stable and smooth performance. Stability and smoothness are contributed to by the frame quality.

Generally, the more you spend, the better treadmill frame you'll get. That said, you really need to assess:

  • how often the treadmill will be used
  • the weight of the user (s)
  • the intensity of the use (ie walking vs. sprinting).

The more often, heavier load, and higher intensity a treadmill will be used, the better quality frame you should buy.