How do treadmills affect your running performance?

Attis Fitness
4 min readMar 29, 2022

Whether you prefer to enjoy your runs outdoors or not, chances are at some point, every runner has had their go on a treadmill.

And why not? It’s great for quick, structured workouts and helps ease the burden of running out and about in bad weather. While the treadmill does come with many pros (and cons, as you can read in our previous blog post here), one aspect that is not always considered is the long term effect that treadmill running can have on a runner’s gait.

Research has found that there are a few small differences between how your runs when using a treadmill to how you run in an outdoor environment.

While these differences in your running gait are only small, understanding how treadmills can affect these changes could help you to monitor your running and keep yourself both injury-free and performing efficiently.

Stiffness of the Surface

One big difference you’ll notice in your running is down to the change in the texture of the ground between indoor and outdoor running, in particular, the soft nature of a treadmill belt.

Research has found that runners tend to rack up the most miles on concrete which is tough, hard ground and considerably contrasted to the spongey belts found on treadmills.

Why this matters is that, for most runners, running on a softer surface every once in a while is good for giving your legs a break from the solidity of concrete, yet in the long-term, this softness may lower your threshold for running on the hard ground if using the treadmill regularly instead of outdoor running.

Injury Recovery

In some circumstances, such as returning to running after injuries like lower-limb stress fractures, returning to running on a treadmill is a suitable and good way to get back into the swing of things and help improve recovery.

That said, for other injuries, such as returning after a calf or achilles injury, running on a softer surface of a treadmill could prove detrimental, as you’d be better off easing back into a harder ground to avoid straining your calf muscles and aggreviating your conditions. Treadmill running has been found to place a bigger strain on the soleus muscle within your calf, and as such, could hold up your full recovery.

Belt speed variation

Another thing to consider when thinking about the effects of long-term treadmill use on your gait is the speed of the treadmill belt, which research has shown does contribute to your biomechanics.

For example, on older treadmills, the speed can become inconsistent, in particular, when you’re running fast. Over time, this inconsistent, fluctuating speed is not ideal if you’re training to run with a set pace goal in mind, so be sure to always check your equipment is working properly.

In terms of harder, more gruelling and regimented workouts, and if running outside is an option, then many would argue that the reliability of outdoor running may be beneficial for achieving targeted paces and form.

Comfort level

It’s also been found in recent studies that runners who are used to running on treadmills are less likely to actively change the way that they run.

In contrast to this, individuals who weren’t avid treadmill users showed a tendency to actively alter their stride, while also displaying a slight increase in energy cost, meaning that a typically comfortable pace would instead feel a tad more difficult — a discomfort which, if consistently felt, can lead to a change towards shorter stride lengths.

Of course, if you’re a runner who typically runs outside rather than on the treadmill, you’ll expect to feel a little difficulty adjusting to the new format of running.

As such, it’s advised for new treadmill users to think of the equipment as a training tool, rather than just the place you go for a run, and as such, you should aim to start slowly and work your way up towards a full and typical run as you adjust.


Treadmills are an undeniably useful apartus for aiding runners in times of injury recovery, structuring training schedules, and getting runs in when you fancy escaping bad weather.

But certain factors may come into play when using the treadmill reguraly that could have an impact on aspects of your running, from the softness of the ground, the pacing of your runs and the comfort and ease at which you can perform.



Attis Fitness

Attis Fitness has developed the next generation of fitness trackers — STRIDENSENSE.