For today’s edition of Dear Mark, I’m answering a couple questions from readers. The first one concerns cupping, the controversial therapy used by dozens of Olympians, including most notably Michael Phelps. What does it do, if anything? How does it work, if it even works? And then I discuss the need for increased protein intake in the context of losing lean mass. We want to lose fat, not lean, remember, and there’s evidence that increasing your protein intake can preserve lean muscle. Especially when you’re exercising a ton and eating low-carb.