Ah, gotcha. I agree with the Medium author, and disagree with the book's author - at least, I disagree with the absoluteness.

The point he's making is that running/exercise cause your body to compensate with a metabolism rate shift. Fair enough.

However, that does not mean you can't lose weight through exercise. Settle into a rhythm of 12 hours per week training, and your challenge becomes maintaining weight.

That's what I'm disagreeing with. I've seen it first hand - a whole team of people, training 12 times a week, performing highly, peaking for a race - and having to try very hard to NOT lose weight.