Sumo wrestlers come in many sizes. Unlike in American wrestling, there are no weight classes. The heaviest and tallest man may be pitted against the lightest in any tournament. Naturally, being heavier does have its advantages. However, weight alone isn't king. Balance can trump weight.
Anyone who has seen a smidgen of a sumo bout has likely seen the wide-leg squat stomping that happens at the beginning of a bout. This stomping is, on one hand, ceremonial. The sound of the stomping is said to scare away demons. On the other hand, this stomping is a major part of how sumo wrestlers train.
The reason for this squatting is to improve a rikishi's balance. The rikishi (wrestler) squats low, with legs wide apart. Then he will stomp each leg, lifting it as high as he can in the stomp. He then practices lifting each leg wide to the side in a series of kicks.
A wrestler in training will do around 500 of these kicks and squats each day to improve his balance.
In recent years, the sumo squat has caught on with fitness enthusiasts. Some say it is not only effective in balance training, but its a great workout because it works every muscle group in the body.
Maybe I should give the squats a shot.