Are Treadmills Bad for Your Knees?

Treadmills are some of the most popular types of cardiovascular exercise equipment for running or walking indoors. A high-quality treadmill can go both slow and fast, and they can get you into that fat-burning cardio zone in no time at all.

A great treadmill can come loaded with features other than speed control, features like incline control, workout programs, pulse monitoring, and more.

There’s no doubt that running on a treadmill and doing cardio is essential to human health. However, how healthy and safe are treadmills? You may have heard that treadmills can be bad for the knees, which is both true and false at the same time.

It all really depends on your current state of health, how you are running, your speed, the quality of the treadmill, and more. Are treadmills bad for your knees? It’s not a black and white or yes and no kind of answer. Let’s explain.

Good Health vs. Pre-Existing Health Conditions

Generally speaking, if you are a young and active person in good health, and of course without bone and joint problems, then running on a treadmill will likely not be bad for your knees. Yes, running on a treadmill, especially if you are going fast, will produce a good deal of impact. This impact gets transferred to your ankles, hips, back, and also your knees.

For people who are healthy and in prime shape, these repeated impacts from each step are not going to make a big difference. It might be uncomfortable to suffer heavy impacts to the knees for hours on end, but for the most part, people in good health have nothing to worry about.

Although, all of this said, very heavy and repeated impact to the knees for a very long time (over months or years) may have negative effects, but if you’re healthy to begin with, it’s going to take a lot for a treadmill to do any sort of damage.

The problem to think about is any pre-existing health condition. If you have bad knees, you are suffering from old injuries that never healed, you have arthritis, osteoporosis, or any other such condition which can weaken bones and joints, cause pain in bones and joints, or decrease mobility, then the impact created by running on a treadmill will be bad for the knees. If you are running on a treadmill and already have issues with your knees, each and every impact is going to make it worse.

It Depends on the Speed

Running on a treadmill may or may not be bad for your knees depending on the speed at which you run or walk at. Simply put, the faster you go, the higher the impact is going to be. If you are just walking at a slow pace, then the impact created is going to be very minimal.

If you are jogging, then there will be a bit of impact. Of course, if you run full pelt, there will be a lot of impact. Therefore, even if you do have existing knee and joint issues, just walking on a treadmill is not going to make much of a difference.

However, if you do have pre-existing issues, and you run on a treadmill, all of that impact from each step is going to hurt, and it also comes with the potential for long term damage and pain.

It Depends on the Incline

There is research which proves that walking or running on an incline does indeed help to reduce the impact created with each step. It is shown that increasing the incline from totally flat by as little as 3 degrees can reduce the amount of impact created by as much as 24%.

Therefore, if you are worried about damaging your knees or making an existing condition even worse, putting the treadmill on an incline will make a difference. The greater the incline, the less the impact created. If you speed walk at a moderate incline, the impact created should be very minimal.

It Depends on the Treadmill’s Cushioning

Something else that needs to be considered is how well-cushioned the treadmill in question is. There are treadmills that just have a belt on a rather solid platform; there are treadmills with plush belts that can absorb impacts; and there are also treadmills with so-called Comfort Tech Systems.

This is more or less a suspension system located under the belt which works to absorb the majority of shock and impact created with each step taken. These impact reduction systems may not take away 100% of the impact, but they’re better than nothing at all.

It Depends on Your Shoes

Yet another factor that is going to make a difference is your footwear. If you are wearing something like skateboarding or basic walking shoes on a treadmill, they won’t do you any favors. What you want to go for is a real pair of high-quality running shoes.

Good running shoes will have good insoles and midsoles with arch support, stability features, and impact absorption, or in other words, cushioning. The more cushioning and shock absorption capabilities your shoes have, less impact will be transferred to your knees.

Even if you are in perfect health, wearing the wrong footwear can lead to some serious issues rather quickly. On the other hand, even if you have existing joint and knee issues, the right pair of shoes can go a very long way in relieving pain and discomfort.


Running on a treadmill is not going to be great for the knees either way. However, if you are in good health, run on an incline, don’t go full pace, and wear the right shoes, you should be just fine. Even if your knees are not in the best shape, the various factors discussed above can all make big differences and still allow you to use a treadmill comfortably.