Brandon Fisher
Master Black Belt
Responding to this and the orginal question: Everytime I get a chance to be with a senior Grand master who still has great ability because they have been faithful to thier personal training it is truly and inspiration to me and others to make thier personal training a priority. However because a high rank may or may not look a certain way for many reasons do not be fooled into thinking they have nothing to offer. All things are not always what they seem.
That being said depending on the style 10th degree is usually reserved for one person only at a time possibly the head of the organization and that and higher degrees are usually reserved based on age and what that person has contributed globally not being able to leap a tall building in a single bound.
Those who have kept up thier personal training have adapted with age apropriate training like swiming daily and other regimines.
Usually if you need references or political courtesy or in the case of higher learning skills a 8th dan and higher will only be allowed to participate or you need thier recomendation that a 5th Dan cannot do for you.
You can always tell when you are in the pressence of the real deal.