He should talk to Barkley, who was really fat and out of shape. Once he got into shape he was awesome. He credit Moses Malone for getting on his case and making him or helping him lose like 50 pounds. But that was back in a different era when the young guys had older mentors to kick their ass into shape.
Zion comes in with all the hype in the world. There isn't a strong vet on the team to get on his case. His team is too young. Maybe CJ McCollum could get on him a bit? He would need someone like a LeBron or a Draymond Green type guy to bust his ass.