You were replying to a poster who said that McAtee could benefit from some gym/muscle work. You replied that, "There is nothing wrong with James' physique. It's not a hinderance in any way."
I was suggesting that, while you've seen a lot more of him than I have, so have a better idea of his strength, most 19 year old athletes would be able to improve their muscle strength considerably.
You'd previously replied to a post where I pointed out that Pep likes players who can hold onto the ball in tight spaces under pressure, which requires a lot of strength. So, not big muscles, but strength, and that does develop a lot in the early 20s.
I'm not suggesting he's weak compared to other 19 year olds, and I think he actually looks pretty strong already - just suggesting it's not daft to suggest he could come back a better player due as he's strengthened up a little through necessity in the Championship.