I read while walking on the treadmill, keeping the speed set pretty slow. I also read while walking outside when the weather is good at a track nearby. I take a lap around before starting to read to see if there’s anything to watch out for since it’s a dirt track that’s not always maintained well. I find that a lot of the time, I end up reading more than if I’m sitting. I’m on autopilot for the walking after a minute or two and then my focus is all on the book.