This is a man who was an Olympic wrestler in the 1990's and is still considered one of the top fighters in the world in the closing months of 2011.
That kind of longevity is impressive, and now that Randy Couture has retired, it could be argued that Henderson is the best "old" fighter in the UFC.
Of course, that isn't to say he is alone in this. There are plenty of mixed martial artists out there who are still able to compete with the best.
Here are the top five fighters outside of Henderson who prove that age is just a number.