Kant was so famous for taking a daily walk at precisely 3:30 p.m. that the residents of Königsberg could set their clocks by it.

Lots of famous historical figures walked. Darwin, Jefferson, Nietzsche, Dickens, Thoreau. More recently (obviously): Jobs.

I wrote a small piece a several years ago on it but have found walking immensely helpful in my debugging efforts. And there's so much research that backs it up.

Hence the popular expression "It's good to be punctual, but you don't have to be a Kant about it"