[93po]

You don't get motion sick on a treadmill because you're not wearing a VR headset. There's no forward motion of your head captured with your eyes to mismatch what your vestibular system is feeling.

[dr_kiszonka]

To add to your point, there is a somewhat unpleasant sensation once you get off the treadmill, i.e., even if you are standing in place, it feels like you are moving forward.

[aspenmayer]

This reminds me of the similar weird sensation of phantom movement after jumping on a trampoline.

[berniedurfee]

I actually do get a bit of motion sickness when I get off a treadmill. It takes me a couple minutes to get my bearings after stopping.

[c0pium]

This is incorrect. You don’t get motion sick on a treadmill because the small accelerations and decelerations match what your eyes are seeing. There is motion.

[93po]

I agree there's motion, I'm saying there isn't a mismatch with what your eyes are seeing, which is what causes the motion sickness