My brother in law is 6-2, 340 at 28.
But he was an offensive lineman in HS and college until knee injuries ended his career as a sop re. He goes to the gym three times a week, works a physically demanding job as a in-house caretaker, but while better, his old bad habits of eating, and mostly weight training with little actual cardio, plus his bum knees, make it tough to lose the weight.
I've seen him run while playing sports. The guy runs like 40-yo Sabonis.
Where's the line drawn? For what it's worth, he's raising his 6-yo kid to be active in youth soccer, teeball, and MMA.