The lineman in the NFL are athletes and train like it and to sustain their larger size they have to consume an absolute fuckton of calories. There was an article about an ex Chargers player Nick Hardwick on here the other week detailing what he had to put his body through during his career.  After watching Hard Knocks and seeing how agile Vince Wilfork was in training really surprised me. I remember thinking for sure that after his career he'd lose the excess weight easily, that was until I saw his wife on the show haha. (She's fat af)