You may believe that pain exists in your joints or in your muscles. In truth, pain is simply an action signal perceived by the brain. In some cases the pain is real. Yes, you really did just smash your thumb with a hammer. But sometimes the pain is actually a false alarm. That trick knee of yours, you know, the one that's been bothering you for the past 6 years? Yea, it was actually healed 4 years ago. But since it was such a striking threat to your brain, it has very easy access to the receptors in your brain associated with it.
You see, your brain could spend a lot of time and energy trying to create a new pathway in your noggin to tell you, "Hey, your ankle is not very mobile and I'm worried that should a saber-toothed tiger jump out from behind the copier and try to eat us, you won't be able to run away." Or it can just say, "Knee... I command thee to ache."
Yea, your brain (cerebellum) is still stuck in the stone age. It very much sees the world through a threat/no threat lens. And your brain has no problem taking you down a notch to protect you.
Think of it this way: You have the ability to tear yourself apart, but it's your brain that throws on the brakes, making you less strong, or less mobile. It will also do it with pain. Hard to help someone move a Jacuzzi with that bum knee, or bad back, right?
Using Z-Health R-Phase (rehabilitation, reeducation, restoration) drills we can calm your nervous system, telling your brain "Its cool, I can take that tiger...".