think about how thick jays muscles are. afetr a workout, not only has he burned up a whole lot of fat, but lets say he trains chest and he fully depletes his pecs of glycogen. (which he probably comes close to doing, given that he trains like at least 25 sets per body part) that is a shit load of carbs to replenish that glycogen ! and isnce he eats low fat diet, his body is burning up fat the whole time after the gym untill his body repleneshes that glycogen.