I had hope at one point to set up a Kindle with large fonts on a treadmill, but that was just totally hopeless. I tried again with a music stand next to the treadmill, but it was too far away, badly angled, and touching the device to flip pages could still turn it off.
And it's not just the accidental power-off, it's also the accidental power-on. I slip the Kindle into a tight pocket in my backpack, and it sometimes turns on by itself. Further, inserting it into the pocket can sometimes reproduce the swipe motion, so it can be on and active (and sometimes randomly page-flipping) inside my backpack.