Rock solid. No, we ain't talking about the thick slabs of meat that hang from your frame -- those are easy to see, simple to assess. We're talking about your joints, bones, ligaments and other support structures that make lifting possible. The stuff you take for granted, what you can't see but can definitely feel when there's a problem. All too often, lifters focus only on building strength without thinking twice about the underlying support structure. Truth is. you are only as strong as your weakest link. If your weakest link is your joints, then you increase the risk of injury and that means you're out of the game.