One Dirty Magazine

Getting the Most from Your Treadmill Workout

What you need to know to get the most out of winter treadmill runs.

David Roche December 10th, 2018

Getting the Most from Your Treadmill Workout Photo provided by David Roche

The treadmill is often a necessary evil, like road running or wearing pants. Sometimes, it’s about the conditions, with ice and cold outside or darkness that makes it unsafe to run where you live (or bad air quality outdoors). I have also seen athletes rely on treadmills due to parenting duties, being on call at the hospital or just wanting to finish that show on HBO (“Barry” is that good). Whatever the reason to run inside, it doesn’t have to be a drag. Treadmill running can actually enhance training by providing an all-weather, all-situations training stimulus.

In 2017, Ryan Kaiser did almost all of his training for the Sean O’Brien 100k on the treadmill, finishing 2nd and getting a Golden Ticket to Western States.

Before the 2016 Way Too Cool 50k, my wife and co-coach Megan did her weekday running at 3 AM on a treadmill before rotations in the hospital. She went on to have one of her best races. In 2017, Ryan Kaiser did almost all of his training for the Sean O’Brien 100k on the treadmill, finishing 2nd and getting a Golden Ticket to Western States. More recently, US road marathon champ Brogan Austin has talked about doing many of his workouts on a treadmill. And there are countless similar stories among all levels of athletes. So depending on your background and goals, maybe the treadmill can be a bit less evil, and a lot more necessary.

Here are some basics of what you need to know from the research and coaching worlds to get the most out of winter treadmill training.

Grade to Simulate Level Running

A seminal 1996 study in the Journal of Sports Sciences found that at faster paces, level ground outdoor running most closely correlated to running at 1% grade on the treadmill. That study had nine trained male runners adapted to treadmill running do six minutes at varying paces on the treadmill, along with one six-minute bout outside on level ground. At 7:09 minutes per mile pace, 1% on the treadmill and flat outside were the closest analogues. At 8:03, there was no significant difference between 0 and 1%.

The takeaway is that the 1% number does not apply universally to all paces. The authors theorized that the difference could be related to some energy added by the moving treadmill belt, changes in form due to varying surface outside, air resistance or even different visual cues. At faster paces, the treadmill belt and reduced air resistance may play a bigger role. Most athletes are not going 7 minute pace or faster all the time, so it’s probably not that important what grade is used.

Taking it a step further, the exact correlation to outdoor level running is probably not key for training. Most treadmills are not perfectly calibrated (as discussed below), so worrying too much about that pace number is probably unnecessary. Plus, outside the lab, there are likely other variables that play a larger role than minor variations in grade, like temperature, air flow and how much egg nog you had last night. Instead, make individual decisions based on your goals, background and how it feels. As I tell my athletes, I care about how you feel, not what the numbers say.

The takeaway is that unless you’re doing specific pace workouts (like people training for a road or track race, like Brogan Austin mentioned above), you don’t need to be dogmatic about the grade, and it’s probably best to mix it up a bit anyway.

Using Grade to Correlate to Speed Increases

A benefit of treadmills is that you can closely control grade and pace to get workouts that strategically target the desired goal. However, some athletes don’t love going fast on treadmills, especially lower quality machines that shake and shimmy as if they’re practicing a hot new dance craze. That’s where grade adjustments come in.

In Daniels’ Running Formula, Dr. Jack Daniels correlated different speeds and grades with oxygen uptake. The specifics of the calculation are probably not useful for most runners unless you bring a slide rule into the 24 Hour Fitness, so you can use this calculator to get a solid feel for how grade and pace are interrelated.

Don’t find yourself beholden to pace or distance numbers when your body processes that input differently than others, or differently than you might when running outside.

A good example is if you want to do intervals around 6 minutes per mile, but don’t have the energy or machine to handle that pace. According to the calculator, you can do 7:30 per mile at 6% grade to get a similar stimulus. The theory is that power output is similar, even as pace changes. Just remember that at some point, you actually need to go fast to adapt to the unique biomechanical demands of quicker running.

Perceived Exertion

Different people perceive stimuli differently. That seems like an obvious statement, but I think that all-too-often, runners judge themselves by metrics that work for others, rather than themselves. The treadmill involves different feelings of perceived exertion than outdoor running, even for athletes with similar backgrounds and fitness levels.

I cited my wife Megan’s treadmill running in the intro. Well, I am the exact opposite. I have run on the treadmill a couple times in my entire life, just to test out workouts for athletes. Both times, I decided that treadmill running was im-freaking-possible and stepped off quickly after getting the data I needed. It just doesn’t work for my brain (though I imagine I’d suck it up if I lived in Barrow, Alaska).

That gets back to the general idea that perceived exertion can vary across people (or within the same person at different times). Studies show music can change how a workout feels, even changing baseline physiological responses. Visual cues or being given positive reinforcement can do the same thing. My hypothesis is that for my brain, treadmill running is the ultimate in negative reinforcement, turning what I consider a joyous act of self-expression into a numbers game. Megan might be motivated by the very thing that undermines me. It’s similar to how different athletes might run with music, while others think it’s a horrid cheapening of the sport.

There is no right answer, just be aware of how you might differ from other athletes. Don’t find yourself beholden to pace or distance numbers when your body processes that input differently than others, or differently than you might when running outside.


All of this deemphasis of numbers is especially important if the treadmill you use is not carefully calibrated. Minor variations in construction or use over time can cause the reported pace and the actual pace to vary by small margins (and sometimes, supersized margins). Since even 0.1 miles per hour can be close to 10 seconds per mile at some easy run paces, little differences can really change workout design.

Instead of worrying too much about the exact number, be attuned to feel, since the treadmill could be telling you some dirty, rotten lies, making you think you are slower than you are. Or, it could be telling you that you are faster, in which case it’s okay to believe it.

Putting it all together, the key on the treadmill is to go by feel. Your treadmill experience may vary from someone else’s, and that’s okay.


Small increases in temperature can reduce performance substantially by lowering power output and raising perceived exertion, as outlined by a 2016 article in the Journal of Applied Physiology. That performance reduction can happen at much lower temperatures than some might think, with a 2012 PLoS One article finding marathon performance reductions as low as 50 degrees Fahrenheit. One of the same elements that may make a treadmill slightly easier than outdoor running at faster paces–lack of air resistance–can also make the treadmill harder since there is less evaporative cooling. Plus most gyms are warmer than is optimal for performance.

If you have a home treadmill, consider putting a box fan nearby. If you’re in a stuffy gym, take the temperature into account and reduce pace as needed.

Alternating Movement Patterns

Some research posits that overuse injuries may stem from repetitive motion, rather than hardness of surface. If you set it and forget it with the treadmill, it can become a big old repetitive motion machine, possibly increasing injury risk. (Risk may not be uniform for all types of injuries. For example, a 2016 study found 14.2% more achilles tendon loading force on treadmills.)

I advise athletes to consider mixing it up with gradient to avoid falling into the single-motion trap. Alternating the motion may reduce injury risk (or may not). Either way, it provides you something to do while you’re staring at the wall.

Putting it all together, the key on the treadmill is to consider going by feel unless you are training at very fast paces or for very fast races when the marginal changes in grade or speed matter most. Remember that if the treadmill seems harder for you, it’s not that you are trying less hard or are less mentally tough. It’s just that the specific treadmill interacts differently with your physiology and psychology.

Perhaps best of all, consider putting a towel over the numbers on the screen, get a great playlist and use the time to escape from the pit of despair that can accompany self-judgment. It might not be the most scientific way to run, but it could be way more fun.

—David Roche partners with runners of all abilities through his coaching service, Some Work, All PlayHis book, The Happy Runner, is about moving toward unconditional self-acceptance in a running life, and it’s available now at Amazon.


Leave A Comment

5 Comment threads
3 Thread replies
Most reacted comment
Hottest comment thread
6 Comment authors
JeffAllan HoltzCary StephensAndyDavid Roche Recent comment authors
newest oldest most voted
Allan Holtz
Allan Holtz

I question this calculator. It says 15% slope and 2.3 mph is equivalent to 3.9 mph outside. My heart rate is 90 bpm walking outside at 3.9 mph and 120 bpm walking 2.3 mph at 15% on a Precor treadmill.

David Roche
David Roche

Thanks so much for sharing your story Allan. My guess is that the calculator isn’t entirely accurate when making major adjustments (like from 0 to 15%) and is better for more minor ones. That HR is a great guide!

Allan Holtz
Allan Holtz

Yes – heart rate is a great guide. What is troubling but true is that as we age, our maximum heart rate drops AND our perceived exertion rate at any fraction of our maximum heart rate RISES. I am now 68.8 years (young). Twenty years ago I could run all day at 6 mph/10 minute miles at 120 bpm heart rate. Now, I am still 6 mph at 120 bpm but I can no longer comfortably maintain that pace very long. And I have maintained a high (2000-3500) miles/year effort each of the past 20 years, so my lost of… Read more »


So ironic that you cited the same study I came across only *after* hurting my Achilles tendon on a Dreadmill. I only used it because it was pounding rain outside and I couldn’t take the baby stroller out, so I did my usual 7-miles indoors instead and finished hobbled. I probably went a bit faster than necessary just to get it over with quicker, but not even marathon pace for the most part. Who knew the mill can actually be worse on the Achilles than running on asphalt with a stroller?? If I ever dare use it again, I will… Read more »

David Roche
David Roche

I am so sorry Rachel! There are some studies (that are controversial, so I didn’t cite) about people changing biomechanics a bit naturally on the treadmill, with altered footfall slightly. YOU GOT THIS!!!


Great article David. Sadly, my rare positive experiences with the dreadmill have been for slowly grinding up 15% grade hill repeats. And I’ll only resort to it when it’s in the 30s and pouring rain — otherwise any weather is better than the mill! This mostly comes from one treadmill interval workout many years ago when I strained my knee very badly — my only knee injury in 20+ years of running and 9 ultra seasons! It seems like there there is an unnatural pull or torque on the treadmill (it IS, after all, moving under you) that puts damaging… Read more »

Cary Stephens

Timely article. As someone who occasionally uses the treadmill to get a quick workout in, I find that playing with the grade and speed frequently helps break up the monotony. For instance, today I warmed up hiking uphill at an ever increasing grade (increasing .5% every 30 seconds) until I reached 15% grade. I then started increasing the speed (.2 mph every 30 seconds) until I was pushing pretty hard. Then I slowly lowered the grade while continuing to speed up until I got 1% and 5:40 pace, holding that for the last couple minutes. This was a 3 mile… Read more »


Dave — a question about using foot pods. I have one that measures my stride length and cadence (and tries to approximate power). This shows a pace far different than the treadmill. Shouldn’t stride length/cadence be accurate enough to determine pace? Asking because I am trying to do an early season marathon, but transitioning to road slowly (I ran a trail 100-miler in October just fine, but am getting a bit of shin pain running on roads) Thank you!


HELP US KEEP OUR WEBSITE FREE is completely free. We don’t have a paywall and you don’t have to be a member to access thousands of articles, photos and videos. Our editorial and design team—and all of our contributors—are trail runners just like you who love the sport and want to share all the great things it has to offer. 

But we can’t do it without you. Your support is critical for keeping our website free and delivering the most current news, the most in-depth stories and the best photography in the running world.

For 20 years Trail Runner has committed to excellence and authenticity. Your subscription to our print magazine or donation will help us continue down a path that is uncompromised, and keep the website free for trail runners like you.