If you are a runner, you know that running uphill is dramatically more difficult than running on flat ground. You may have also found that running uphill while outside in nature is harder than running uphill on a treadmill.

This is a common claim among runners, and there can be many reasons why. First of all, while running outside, the hills are not going to be an exact percent incline the entire run. It can be more exhausting to be running up a hill that is constantly causing you to change your effort, so this makes sense. Also, while outside you may be dealing with wind resistance, moving from side to side to avoid sticks or other obstacles, or other similar things.

But, what if you found a hill that was at an exact angle for its entire distance (and there was no wind or other obstacles), and you set your treadmill to that same exact angle, would it still be harder to run outside?

YouTuber Steve Mould set out to to answer that exact question, but he didn’t get the results he expected.

In the video, he created a ramp to simulate an outdoor path that one might run on, and then had a treadmill. He then took a remote controlled car with a device that could read how much electricity was being used.

Unexpectedly, the ‘outdoor’ ramp used 10 watts and the treadmill used 9. They repeated the tests many times and consistently got the same results.

In the video, Mould says:

“Yeah, so it’s harder to go up the ramp by about 1 watt. And that’s really consistent over like loads and loads of tests that we did. It’s always about 9 watts on the treadmill and about 10 watts on the ramp. It’s really annoying.”

Check out the full video here to see it all in action. This is just one of several very interesting experiments on similar concepts that he conducts in the video.

He was, of course, expecting that it would take the same amount of energy regardless of if it was the ramp or the treadmill. He wants to make some adjustments on the test to see if he can figure out exactly why the results show that the treadmill is easier. He believes that the discrepancy may be that on the treadmill, the wheels would sometimes slip so that they were out of contact with the ‘ground’ they were on. This could account for the reduced electrical demand.

He wraps up by saying:

“We need to improve the experiment to figure out if that’s actually what’s going on.”

Hopefully there will be a second video on this test that will explain why running outside seems to take more energy. If he can’t find the problem with the testing, he may have to admit that outdoor running really is harder than on a treadmill.

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