The Rock's a big dude. I'd be surprised if he was "only" 225. Actors lie about shit all the time. It's not too far fetched to think he under states his weight to seem more appealing for a wider variety of roles. As long as he's leaner than he was when he was wrestling is what matters. Also saw a video of him when he was at Miami and he was throwing around 3 plates on the bench like it was an empty bar.