Highly ritualistic and more athletic than initial appearances may imply, sumo is a stunning, charged spectacle that you cannot miss if you are in Tokyo at tournament time.
As a living history lesson, it is a chance to see how Shinto impacted ordinary people's lives. Linked with the rituals of Shintoism, sumo probably originated about 2,000 years ago, but only became a popular sporting event in its own right in the 17th Century.
Sumo's whole visual vocabulary is infused with Shintoist motifs and ideas, from the scattering of salt to the structure and embellishments of the sumo dōyō (wrestling ring). The wrestling matches that were precursors to sumo made up a part of Shintoritual prayers for good harvests.
This is an ancient, disciplined, tough sport. But best of all, it is seriously fun. The rules are simple: the rikishi (wrestler) who causes any part of his opponent's body other than his feet to touch the ground inside the ring, or pushes him outside the ring, wins.
Although wrestler may look like infants on steroids, those prodigious amounts of flesh conceal some very powerful muscle. At the beginning of each match, the victor of the last match offers a wooden ladleful of water to the next wrestler before entering the ring, for the incoming wrestler to perform a symbolic cleansing of the mouth and body.
Before entering the ring, each wrestler takes a handful of coarse salt to scatter into the ring to purify it. Then, squatting at opposite ends of the ring to face each other, they outstretch their arms to the sides, palms raised, to show their intentions for a fair fight.
As they both saunter to the centre of the ring, slapping thighs and bellies, with intimidating stares, they know this process will be repeated again and again for several minutes before they settle into a squat for the final staredown.
When both wrestlers are ready, they suddenly charge at each other and what happens next is an exciting, colourful ritual of unpredictability.
The action during the Tokyo tournaments, or bashō, takes place at the green-roofed Ryogoku Kokugikan in January, May and September. Although the best ringside seats are bought up by those with the right connections, box seats accommodating up to four people are a great way to watch sumo in style. Attendees in box seats can order food and tea from servers dressed smartly in happi (half-coats) and straw sandals.
Cheaper tickets are available for non-reserved seats at the back, and if you do not mind standing, you can pick them up for around $1. Simply turn up on the day, but get there early as smart fans start queuing the night before. Only one ticket is sold per person to foil scalpers.
When a tournament is not in session, you can enjoy the neighbouring Sumo Museum with its displays of humungous wrestler hand-prints, and the referees' ceremonial clothing. Unfortunately, there are no English explanations, and during tournaments the museum is open only to those attending the tournament.
Even more fascinating, if you can swing it, is a visit to a heya (wrestling stable) to witness rikishi - literally, "the power men" - close-up. The most famous of all is Kokonoe Beya, run by the legendary wrestler-turned-big-boss, Chiyonofuji the Wolf, and you are invited to "just turn up".
Other stables are not so open to outsiders, but during tournament season, you are likely to see wrestlers walking around the neighbourhood in yukata (light cotton robe) and topknots. Keep your ears open for their geta (wooden sandals) clopping down the street.
The article 'Tokyo's sumo wrestling scene' was published in partnership with Lonely Planet.