One explanation for the genesis of Japan's national sport, sumo, can be found in Japanese mythology, which says that the gods used to wrestle one another. One wonders if they bothered to do so at 5 a.m., when the modern-day gods of the dohyo get a most rude wake-up call.

Most of the sumo heya -- the "stables" where wrestlers train, sleep and eat -- start their day in the wee hours with some of the most rigorous training imaginable.

There's none of the well-rehearsed, media-directed showmanship of baseball training camps here, nor the pomp and ceremony of a sumo tournament. During sumo keiko (training), even the most junior grapplers stand up to be counted.