Why Is It so Much Easier on a Treadmill Than on the Street?
Is the treadmill harder or easier than running outdoors? Poll runners and you’ll get a lot of different opinions on what feels harder or easier, but the basic physics of running is the same for both. (I promise.) So why do people who are used to treadmills find that they run slower outdoors? I’m going to look at the factors that come into play here and talk about how to adapt if you want to be able to enjoy both.
If you find the treadmill running harder, you probably already know the reason: it’s boring . You have nothing to distract you from your own efforts and the glowing numbers telling you how little progress you’ve made. This is a problem we can train our brains to solve for us over time , whether through distraction, mindfulness, or simply being grateful that we’re not outside in bad weather.
For those who find it easier to run on a treadmill, the main reasons have to do with the environment (heat, hills, etc.) and your mindset (especially your ability to pace yourself). Exercising both indoors and outdoors can help make the transition a little easier. Let’s look at the reasons.
The treadmill is literally no easier.
Before we get into the relevant factors, I want to dispel a few myths. From a physics perspective, running on a treadmill is almost identical to running outdoors under the same conditions.
Treadmill doesn’t move your legs
The first myth we need to dispel is the idea that a treadmill “moves your legs” and thus makes running easier. This is not true. You’d have to exert just as much effort to stay still on a treadmill moving at, say, 6.0 mph as you would to move forward at 6.0 mph on a flat, stable surface. Running is about pushing off the ground to move forward. In both scenarios, you are asking the muscles to push off with a force that will cause you to move 6 mph faster than the ground.
(If the “treadmill moves the legs” theory were true, wouldn’t we have to think of the spinning Earth as a kind of treadmill? And thus running west would be 2000 times harder than running east? Oh well.)
You only need to add 1% incline if you are running very fast.
Then there is the issue of wind resistance. Some runners will say that you need to set the treadmill’s incline to 0.5% or 1% to simulate the air resistance of the outdoors. Even on a calm day, your body has to rise into the air to keep moving. Adding a slight incline to the treadmill should simulate this extra effort.
But this is only true if you run at 7:30 per mile (8.0 mph) or faster. Below that value, “the difference is so small it’s meaningless,” a scientist who has studied the issue told Runner’s World . So if you’re running at 6 mph, you don’t have to worry about accounting for wind resistance.
Now that we understand the physics, let’s talk about why running on a treadmill often feels easier than running outside.
pace
This is probably the main factor (besides the weather) why running outdoors seems harder for someone used to running on a treadmill. On the treadmill, you choose a pace—say, 6 mph, like our example above—and then your body knows what to do.
But in the fresh air, you just have to run and then figure out what pace you’re going at. Even if you have a watch that tells you your pace, it will take a few seconds to minutes to figure out that number. (You may also not be used to reading your pace in minutes per mile if you’re used to seeing your speed in miles per hour on a treadmill, making it even more difficult to determine how fast you’re going.)
So you, a treadmill runner, go for a run outdoors without a clear idea of how fast you are running. You might end up driving too fast, but you won’t realize it until it’s too late and you’ve defecated.
Meanwhile, outdoor runners develop a sense of pacing by necessity. You have to listen to your body and not just look at the numbers to know how hard you’re pushing.
The good news is that pacing is easy for treadmill runners: all you have to do is run outside every now and then. You will learn how your body feels when you move at an easy pace, at a harder pace, or at an erratic pace. It just takes a little practice.
Heat, humidity and other weather conditions.
If all your treadmill runs were in a 68-degree gym, they would all feel about the same. But nature loves to bless us with heat, wind, humidity, rain, snow, ice and similar complications.
Heat slows us down a lot , especially if we’re not used to it. (During the summer, you do develop some adaptations to heat .) Humidity combined with heat makes the situation even worse. Your body can’t cool itself by sweating, so you get hot and stay hot. It’s normal for your pace to slow down for every mile from a few seconds to a few minutes on a hot day.
Strong winds can also slow you down (when you’re running against the wind) or speed you up (when you’re running with the wind at your back). Ice may force you to slow down to watch your position. Snow can make you work harder because your feet sink into the ground and you have to work harder to get them back up.
On the other hand, a cool, dry day is better for your performance than a sweaty gym environment. Ideal running weather (in my opinion) is around 50 degrees, calm and cloudy. Most people will run much faster and feel better in these conditions than on a treadmill at room temperature.
Hills
If you live in a lowland part of the country, you can skip this section. But many of us live where there are hills. Big, small, maybe some mountains. On a treadmill, you can choose what incline you want to run at. Outdoors, your choices may be limited.
I live in a hilly area, so even my “flat” outdoor routes aren’t exactly flat. A standard treadmill is my only truly flat option. Even gentle hills can accumulate over a long run, forcing you to work harder on the climbs but never quite regain your previous speed on the descents.
Various surfaces
The treadmill has only one surface. Every step meets a level surface. Every step is the same softness or hardness. There is much more variation outdoors.
Even on a simple city run, you’ll encounter curbs, slightly sloped pavement slabs, curved road edges, pebbles, debris, and the occasional patch of grass or dirt. Run along the trails and you’ll also encounter compacted dirt, mud, soft grass, fallen leaves, rocks, sticks, logs, small streams to jump over, ruts, carved mountain bike tires – you get the idea. Your feet should land and push off a little differently for each one.
The variety of outdoor running is good for your legs, but can tire out the small muscles in your feet and legs if you’re not used to it.
How to Train for an Outdoor Race If You Prefer to Run on a Treadmill
You can do most of your workouts on a treadmill, but in some situations it may be necessary. A treadmill will allow you to exercise in bad weather, when you cannot arrange childcare during working hours or for a number of other reasons.
The main thing is to at least sometimes run in the fresh air. If you’re training for a marathon, try to run long distances outdoors, even if some of your short runs and speed workouts may be done on the treadmill. Go outside when you can. This way you adapt to the weather, train your legs on different surfaces and develop the muscles and mindset needed to tackle hills .