RYOGOKU, Japan >> Most of us are trying not to gain weight, but that is not the case for the young men picked as potential sumo wrestlers. They could be as young as 15 when they are invited to live at one of 48 sumo training facilities, called stables. These homes provide an intense training ground for the athletes.

Weight can be an advantage in Japan’s national sport. One of the highest-ranking wrestlers out of Hawaii, Salevaa Atisanoe, who went by the professional name of Konishiki, weighed in at about 600 pounds.

A common misperception is that their weight is mainly fat, but to observe them in action — pushing each other across the ring and sweating in 40-degree temperatures — it is clear they are athletes with strength born of muscle.

It is estimated that rikishi, or wrestlers, in training should eat 10,000 calories a day, far more than the recommended amounts for an average woman (2,000) or man (2,500).

To bulk them up, stable masters feed these rikishi chanko nabe, a hearty stew or soup packed with protein and vegetables, along with rice. It’s usually eaten twice a day — the only dish served.

The dish is similar to nabe, a soup with meat and vegetables that is familiar to many Japanese home cooks. Chanko nabe refers to the soup prepared for sumo wrestlers, which is served in much larger portions.

It is debated how the name chanko nabe came to be. One theory is it came from the endearment “to-chan” or “daddy,” often used to refer to retired wrestling coaches, and “ko” from “kodomo,” meaning “child” or “pupil.” So chanko could represent a meal that a teacher and pupils could share.

A recent visit to the Dewanoumi stable in Ryogoku, Tokyo, the historic center of sumo, provided an introduction to one version of chanko nabe, during the first meal, served around noon. The most famous rikishi in this stable is Mitakeumi, who won two Emperor Cup competitions in 2019.

There is no professional cook in the kitchen; lower-ranking wrestlers are assigned to the task. Fortunately, there is no set recipe for chanko nabe. Almost anything goes.

The dish usually starts with chicken broth or dashi, the ubiquitous broth of Japan made from cured bonito (aku) shavings and seaweed (konbu). Some add ginger, garlic and mirin or sake.

The broth will never be made using pork or beef, as those animals have four limbs and symbolize a loss — in sumo only the a wrestler’s feet may touch the floor of the ring; should a hand or knee touch the ground, the match is over. Pork or beef can be added as an ingredient, but not in the initial broth.

The chanko nabe made that day was based on a traditional dashi broth, packed solid with ingredients, including rubbery konnyaku, carrots, daikon, gobo (burdock), tofu, shimeiji and shiitake mushrooms, onions, green onions, cabbage and thin slices of pork belly.

It resembles shabu shabu, or hot pot, but all the ingredients are added at one time, instead of one by one.

The tasty broth was served with unlimited hot rice. I estimated that about 60 cups of raw rice were prepared for a single meal for the 16 rikishi, about four coaches and six guests.

Served along with the chanko nabe were store-bought side dishes of spicy cod roe (mentaiko), flavored bamboo shoots, takuan (pickled daikon), potato croquettes, assorted pickled vegetables and kamaboko (steamed fish cake).

This first meal of the day follows the morning’s practice, which could be a rigorous workout for several hours before eating anything. The workout is so strenuous that it is said mothers cry when they see their sons in training.

Assistant stable master and former rikishi Ryusui Takasaki said that the evening meal, also chanko nabe, may be a kim chee or miso broth, with chicken or fish instead of pork.

Eating chanko nabe twice a day, seven days a week for years, is the traditional way these professionals get their heft. But no matter how tasty, it could get boring, Takasaki said. “The younger wrestlers do monku (complain) a bit.”

HAWAII CONNECTION

The many sumo wrestlers from Hawaii are remembered fondly in Japan. Those who reached the highest levels:

>> Salevaa Atisanoe (Konishiki)

>> Jesse Kuhaulua (Takamiyama)

>> Chad Rowan (Akebono)

>> Fiamalu Penitani (Musashimaru)

CHANKO NABE (HOME VERSION)

• 6 cups dashi (from liquid or powder, combined with water)
• 1/2 pound belly pork, thinly sliced
• 1 cup carrots, peeled and sliced into coins
• 1/2 cup peeled and sliced daikon
• 1/4 cup peeled and sliced gobo (burdock)
• 1 onion, sliced
• 2-1/2 ounces aburage (deep-fried tofu), soaked in hot water
• 3-1/2 ounces enoki mushrooms, or any fresh mushroom
• 6 fresh shiitaki or eryngii (alii) mushrooms, substitute dried shiitakes soaked in water to soften
• 10 ounces firm tofu, drained and cut into 1/2-inch cubes
• 3 cups roughly chopped cabbage

In a large pot, heat dashi on medium-high. Add pork, carrots, daikon, gobo and onion. Cook 10 minutes.

Cut aburage into 1/2-inch slices and add to pot. Cook 5 minutes, then add mushrooms.

Add tofu and cabbage; cook 5 minutes, until carrots and pork are tender.

Serve hot with steamed rice. Serves 6 (or 1 sumo wrestler).

Approximate nutritional information, per serving (not including rice): 340 calories, 25 g total fat, 8 g saturated fat, 25 mg cholesterol, 500 mg sodium, 16 g carbohydrate, 3 g fiber, 8 g sugar, 14 g protein.

Lynette Lo Tom, author of “Back in the Day,” is fascinated by old-fashioned foods. Contact her at 275-3004 or via instagram at brightlightcookery. Nutritional analysis by Joannie Dobbs, Ph.D., C.N.S.