I came across this video, which seems to be a National Geographic special on the Kendo 8th Dan test:

http://kendoshop.com/images/8dan.wmv

The 8th dan is like an 8th degree blackbelt in other martial arts, and it is the highest grade awarded in Kendo through taking a test. The video follows two kendoka as they attempt to pass it.

If you only watch for one minute, watch the segment starting at 17:44. Here, an 80 year old is schooling a 78 year old, saying stuff like, “You’re too hasty. Pretend you’re in a match — wait and grab an opportunity!” and then shoving him back to do it again. It’s great.