Think you or your marathon running buddy are tough? Check out what's required of these monks in the article titled Tendai Marathon Monks: The Run of A Lifetime
The first 300 days are basic training, during which the monks run 40km per day for 100 consecutive days. In the fourth and fifth years they run 40km each day for 200 consecutive days. That's more or less a full marathon every day for more than six months.
That's amazing almost to the unbelievable.