Why does travelling tire you out?

Question

I was a passenger in an almost 4 hour car tourney the other day, and by the end of it I was exhausted. Yet I can easily sit at a desk or in a chair for 4 hours at home doing the same things (listening to music, scrolling tiktok, social media, flash cards) and not feel nearly as exhausted. Why?

In: 21

Answer 1

Three very different responses, all of which seems entirely plausible. I love the internet.