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As with most fitness questions, the answer to, “Is running on a treadmill bad for you?” is: It depends.

It is difficult to give a definitive answer because there are a lot of variables to consider, and everyone’s situation is unique. From a fitness and health perspective, running outside will be a better option for most people. It teaches the body to move itself without the reliance of a machine while also allowing the body to reap more health benefits just from being outside. 

For those who don’t have as easy of access to a safe area outdoors for exercise, treadmill running keeps the activity in their fitness routines. Some exercise is always better than the alternative of no exercise, and whatever allows someone to be the most consistent with their fitness over a longer period of time should be encouraged. 

When making the decision to use a treadmill or not, each person should weigh the advantages and disadvantages for their situation and make the best choice for themselves.

Can Running on a Treadmill Cause Injury?

It’s important to acknowledge that at some point or another, everyone sustains an injury. Injuries can occur while exercising or running, and they can also occur while doing everyday tasks. 

Injuries can be acute, meaning they are caused by a singular event like a fall, or they can be chronic, meaning they develop gradually through overuse. Injuries aren’t always avoidable, because accidents happen, but you can always practice habits that will reduce your risk of injury and potential severity.

pro form carbon t10 treadmill woman walking

When it comes to running on a treadmill (and running in general), there are a few factors that lead to injury.

Being Unprepared

One of the main ways people get injured from a treadmill is that their bodies in general are not conditioned for running when they begin to use one. Instead of gradually ramping up the pacing and distance, they go right into 30 minutes or more on the treadmill. When that happens, it’s likely that their joints are not prepared for that workload. 

Another major faux pas is skipping the warmup. That is how injuries happen: You ask the body to do something it is not physically prepared for. Something will eventually give when the tissues exposed to stress receive too much to handle. This can show up in the form of knee pain, hip pain, or pain in the shins (AKA shin splints).

Overuse 

Even conditioned experienced runners can sustain overuse injuries if they do not take care of their bodies properly. Exercise is good for the body, but it also breaks it down. Resting and recovering is when the body repairs itself from exercise so that it becomes stronger and more fit. Going for long runs on the treadmill day after day without rest and recovery will eventually lead to an overuse injury because it is a repetitive motion and will primarily target the same muscles and joints over and over. 

It is important to make sure you have adequate rest days planned to recover from longer or more intense runs. When you have many weeks of building up intensity, it is necessary to take a deload week to lighten the workload so that your body can fully repair itself. Cross-training is also helpful for injury prevention.

Moving In One Direction

Running on a treadmill only moves the body in a forward motion, but it also needs to be able to move in all of the directions. If running on a treadmill is the only form of exercise, then the muscles that move the body in all the other necessary ways will be neglected and less reliable. 

If you primarily run on a treadmill, include exercises in your routine that also work the secondary muscle groups to prevent muscular imbalances. 

Mobility work is crucial to making sure the joints stay as healthy as possible. Think about including exercises that move the body laterally and rotationally, like side lunges and Russian twists. In order to have the least risk of injury as possible, you need to be able to confidently and comfortably move your joints through a full range of motion.

Advantages to Running on a Treadmill

There are pros and cons to getting your cardio workout from a treadmill. Let’s take a look at the advantages first:

Controlled Pace and Incline

When running outside, the road and terrain can have a significant effect on your pacing. Especially if you are in a hilly area, it may be hard if you are training to hit specific pacing numbers. On a treadmill, the belt will move at whatever speed you set it at, and it is just your job to keep up. 

Being able to adjust the incline allows you to simulate running on hills at exactly your preferred stimulus. Having the option to adjust these variables at your own discretion opens up the possibility for specific interval workouts that can help improve your fitness even more.

Some exercise is always better than the alternative of no exercise, and whatever allows someone to be the most consistent with their fitness over a longer period of time should be encouraged. 

For beginners, both of these factors are key. Starting out with aerobic exercise, you may need some help figuring out what your ideal pace is, or how you handle running on hills. The treadmill is a great place to test the numbers but also easily dial it back if the heart rate spikes too high or the work becomes too much.

Controlled Environment 

When running outdoors, the terrain and weather can be unpredictable. Runners want to be able to trust the surface that their feet are coming in contact with in order to keep consistent strides and prevent injuries like an ankle sprain. 

Bad weather also creates challenges. If there’s precipitation or extreme hot or cold temperatures, you may be less likely to run outside, or more likely to sustain an injury or illness. On a treadmill, the running environment will be the same every time. The surface that your feet are striking will remain consistent, and there will be no weather elements to deal with.

Convenience

Not everyone has access to roads or greenways that they are able to run on consistently. Having a treadmill at home provides the ultimate convenience of being able to run whenever you want. Many excuses for not going on a run or exercising are eliminated when having your own personal treadmill to use in the comfort of your home.

Treadmill deck for Sunny Health and Fitness Treadmill

May Be Easier on the Joints 

Running on asphalt or concrete can increase the impact on the joints from running. A treadmill’s construction absorbs the shock and impact from the ground with every foot strike. Setting the treadmill at a slight incline can also help reduce the impact on the knees and put more focus on the glutes and hamstrings. Curved treadmills are even easier on the joints and get more posterior chain engagement.

Disadvantages of Running on a Treadmill

There are a few reasons you may find treadmill workouts to be challenging:

Changing Your Gait

It’s possible that running on a treadmill can change one’s gait. In fact, research suggests that several key parts of your running form are different on a treadmill than they are if you run outside. 

This happens for a few reasons. For starters, treadmill cushioning isn’t as hard as an asphalt road. Also, the moving belt turns at whatever speed it is set. Therefore, your turnover has to match the speed of the belt, which can take some getting used to. 

Researchers found that people running on a machine would change their stride, the position of their foot strike changed, and there were other deviations from normal running form as they acclimated to the exercise. 

Does this have major implications? Probably not; for people just trying to burn calories and improve cardiovascular health, you will still accomplish that with a longer stride and change in foot strike. If you’re a seasoned runner concerned about form, however, you need to at least account for the change you might feel moving from outdoor running to treadmill running.

It’s worth noting that using a self-propelled treadmill could prevent these effects. Also, there are curved treadmills that actually promote better running form.

Coop running on the Tru Grit Grit Runner for the Tru Grit Runner review

Can Get Boring

Running in place can get boring very quickly. The scenery stays relatively the same. Moreover, there is a screen right in front of you tracking time and distance. Watching the seconds and tenths of a mile tick off can make a run seem even longer. 

Running can be a chore for most people, and having to do it on a treadmill may make it even less enjoyable and exciting than when outside with changing views and nature to observe. Running outside may also give a sense of accomplishment as you can visually see how far you have gone as you work toward your fitness goals.

Getting Access to a Machine

A quality treadmill can be expensive and take up a lot of room, eliminating the option for some to have one at home. This means that you will need to get a gym membership to have access to one. Along with a membership, now you have to fit in gym time into your schedule to get your running in. If you are only able to make it during peak hours, then you may find that many of the treadmills, if not all, are taken. 

For running outside, you just need your body, and a decent pair of running shoes.

RELATED: How to Choose Running Shoes

Less Time Outdoors

People spend a lot of time indoors because of things like work and school, meaning they miss out on the benefits of being outside in fresh air and sunlight. Spending time outside can help to relieve stress and anxiety. Sunlight helps to produce vitamin D in the body, an essential nutrient, as well as boosting serotonin in the brain, which helps to keep you calm, positive and focused. Running on a treadmill inside denies the body of all these added benefits.

Final Thoughts 

There’s both advantages and disadvantages to consider when thinking about running on a treadmill. Whether or not running on a treadmill is “bad” depends on each person’s individual circumstances and how they apply the use of a treadmill in their exercise routine. 

Running outside may be better for the body than a treadmill in terms of preserving a natural gait. A treadmill can still provide the benefits of exercise and may be a good lower-impact option compared to running on a hard surface. If being able to use a treadmill makes the difference between someone running or not, then they should use the treadmill.

  • Running outdoors will more effectively improve running capacity because the legs have to do all the work to move the body, whereas a treadmill goes at its pace regardless of the body’s effort. A treadmill also removes the other positive physical and mental health benefits of being outside while being less mentally engaging.
  • Using a treadmill will allow control over more variables during your run such as pace, incline, running surface and running environment. It will also be easier on the joints than harder surfaces like asphalt and concrete.
  • Injuries from a treadmill typically happen from overuse. That can mean not being physically prepared enough for the amount of running being done or not giving the body enough rest and recovery from a high workload over a longer period of time. Listen to your body and give it rest when it is becoming worn down and not responding as well to exercise.
  • If you are going to use the treadmill, it is important to include other forms of exercise and movement to keep a balanced and physically healthy body and also reduce injury risk. Including strength training and mobility work will not only keep you healthy but also get more out of your running.

FAQs About Treadmill Running

Is it better to run on a treadmill or outside?

For someone with no joint issues and access to safe roads or paths to run on, running outside may be the better choice. There are more health benefits to running outside and it will improve your running more than being on a treadmill. However, if you need a controlled space and environment, then running on a treadmill is better.

Is running on a treadmill every day bad for you?

Ideally, it is good to take at least one rest day a week. Running every day is fine as long as you cycle your workouts with different distances and intensities. Going for long runs every day will eventually wear down the body. But varying between long and short or high- and low-intensity can help to allow you to run more often.

Is it healthy to run on a treadmill?

I wouldn’t say running on a treadmill is or isn’t healthy. It depends on how you do it, how often and how much. Using it as a way to supplement outdoor running when you can’t make it outside is a perfectly healthy way to incorporate the treadmill. But using a treadmill so much that your body breaks down faster than it can repair itself will make it unhealthy, as with any other form of exercise. When done in moderation, it can be as healthy as any other cardio.

Is running on a treadmill worse?

Running on a treadmill has its pros and cons, as does running outside. Running indoors eliminates the additional health benefits that come with spending time outdoors, and treadmill running can also have long-term implications on your gait and technique. But, if a treadmill is the only way you can get cardio exercise in, it’s far better than doing nothing.  

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