Many people are afraid of running because between 30 to 70 percent (depending on how you measure it) of runners get injured every year.

We love comfort, and people make a lot of money selling us comfort, but I would challenge the notion that comfort is usually good for us.

Paper after paper, study after study, have shown that chairs give us back problems because they shorten our hip flexors, give us weak backs, of course it make us sedentary. We take years off our lives probably by sitting in chairs, but we like them because they're comfortable. You go to an African village, you find me a chair with a back. That's a rare thing out there.

... this idea, that humans are essentially weak creatures, is actually deeply woven into a lot of the ways in which humans think about our bodies.