I used to get motion sickness as a child. If we were out on a family trip, I would often have to ask to park up to let the nausea subside, otherwise I would throw up. That has improved massively as I've got older, but I do, and always did, experience a lot of tiredness from travelling. However, I think that is a separate thing caused by sensory overload from all the loud noises and too many things moving too fast in my vision - I can find it hard to talk to a travelling companion too. If I can do so safely, I often try to snooze during the journey, or at least "zone out" with my eyes closed, to minimise the sensory overload. Public transport is the worst, because I'm also surrounded by people in a very enclosed space, which would be tiring even if there weren't also the movement and noise from the vehicle. I avoid it wherever possible, but unfortunately I'm rather reliant on it, as my sensory processing impairments mean that I'm unable to drive.
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