What’s the difference between the competitors who have a smile on their face no matter the race day conditions and the ones who hide out in their car if there’s even a little bit of light rain?

Having access to a treadmill can be a lifesaver sometimes. There are some instances where the treadmill is literally the only option to get in a run. Runners tend to be split on the issue: There’s the “dreadmill” camp that would do anything possible to run outside no matter the conditions. And there’s the “treadlove” camp that could easily spend a couple of hours ticking off the miles on the treadmill.

We’re not here to say one or the other is “right.” If you only enjoy running outside, do that as often as possible. If you only enjoy running on a treadmill, have at it.

That said, if your main goal is to run fast times outside on the roads, you will benefit from the specificity of training outside when you can. Where the treadmill can get problematic for road racers is in two main scenarios:

When the treadmill can become a problem

1. If you learn to only run speedier session on the treadmill

2. If you always stay inside if the weather isn’t ideal

In both of these cases, you’re missing out on a key variable: specificity. You need to run fast outside on race day, so you need to practice running fast outside. And you don’t get the option to race on a treadmill if it’s raining or humid or windy.

Bill Bowerman, who was the head coach of Oregon and was a founder of Nike, famously said of training in the elements, “There is no such thing as bad weather, only soft people.” As a man who trained in the highest reaches of the Rockies to be a soldier on skis, who then fought on mountaintops during WWII, and then spent his entire professional career in a place with much higher than average precipitation, it’s understandable that he would become a stalwart when it came to not letting the conditions make a call about running inside versus outside.

Running on the treadmill slightly changes how you run. Even if it’s small, the treadmill does some of the work by pulling your leg back on the belt. If all you do is run on the treadmill then you’re not working on all the muscles that are engaged when running on land.

I’d like to think that Bowerman, who famously built not only the ideal shoes for his runners but also was known for tinkering with all sort of other running tech, would accept that there are situations where it actually would be more beneficial from a training standpoint to utilize something like a treadmill.

Given these considerations, are there times when the treadmill is the best option for someone who is training for an outdoor race? Absolutely! It comes down to safety and injury prevention.

When you should run on the treadmill:

• Run on the treadmill on days when the weather/climate conditions are a legitimate safety risk (heavy winds, lightning, wildfire smoke, or sub-zero temperatures, for example)

• Run on the treadmill on days when the footing outside will not allow you to complete the spirit of the workout (ice or very heavy snow that can create risk of falls at faster speeds)

• Run on the treadmill if you are returning from an injury or illness and need the option to stop at any moment

• Run on the treadmill if you’re parenting and can’t leave the area where your kid(s) and treadmill are located

• Run on the treadmill if it’s not safe to run outside due to unlit streets in the dark or an unknown area.

The treadmill is a great tool to be used in training. It can help provide us a safe and known environment that that has it’s benefits especially when the weather turns sour. But, if you’re training for a race that is not on a treadmill, it’s good to spend as much time as possible outside. Practicing how to adjust your pace without pressing a button, and learning how to respond to an ever changing environment is an important aspect to learn.

Remember that safety and health always come first and that any run is better than no run at all. Sometimes stepping on a treadmill feels like less work than going outside, and that is just fine! Use the treadmill as a tool to help you make the most out of your running but don’t let it become a crutch to where you forget what it feels like to venture out the front door.