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by maximus-decimus 877 days ago
But on a threadmill you're going in a straight line and usually at constant speed. A constant speed, you don't have acceleration.
2 comments
leereeves 877 days ago
Exactly, you don't have acceleration, and the world around you isn't moving relative to you, so there's no mismatch.

The treadmill shows that performing the walking movements without acceleration doesn't generally cause motion sickness.

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c0pium 877 days ago
> you don't have acceleration

If you actually use a treadmill, or watch motion capture, you’ll see that this isn’t the case. It’s a lot of slight accelerations and decelerations. The variation change from person to person, and more experienced runners are able to minimize them, but they’re still present.

Edit: this study is peripherally related https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8160945/

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leereeves 877 days ago
> It’s a lot of slight accelerations and decelerations

Isn't that always true? If I pay attention to it, I notice a lot of tiny movements of my head, as I just sit here typing.

"You don't have acceleration" is just talking about the big accelerations from 0 mph to roughly 3 mph to 0 mph, not implying that you're completely motionless as if frozen in ice.

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c0pium 877 days ago
Acceleration is change in velocity and change in time, either can effect the apparent amount of acceleration. The velocity you accelerate to or from is just an implementation detail.
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