Michael Phelps' lungs—those that secured him enough Olympic gold to start a mint—are made for a stupendous high, reports Slate. They hold twice the smoke of an average human's, speeding up his THC absorption. But at his size (6-foot-4 and 195 pounds), Phelps needs a lot more weed than smaller users to feel the effects. And if he keeps it up, research shows that lung capacity will shrink—slowing his buzz and his swim times.
(More Michael Phelps stories.)