Secrets of the sumo wrestler's diet

After watching sumo wrestlers grapple, collide and throw each other around the straw ring at the Ryogoku Kokugikan Sumo Stadium, many wonder, what could have made them so big and so fast? The answer is two-fold: training, of course, but also diet.

Weight gain is a crucial part of sumo training since there are no weight divisions in the sport. According to Nihon Sumo Association, 40 out of 42 wrestlers in Makuuchi, the top division, weigh more than 140kg (as of January 2010). The heaviest wrestler, Baruto from Estonia, weighs in at a whopping 188kg. A sumo wrestler's daily caloric intake can reach 8,000 kilocalories, more than twice that of an average Japanese adult male.

A stable manager on the diet secrets

Starting the day with an empty stomach is one of the secrets of a sumo wrestler's training, says Tetsuhiro Matsuda, manager of the Takasago Sumo stable.

"You can’t move quickly with full stomach. Sumo training is more intense than you ever imagine," Matsuda says.

The Takasago Sumo stable is home to Yokozuna Asashoryu, the Mongolian-born grand champion, as well as top wrestler Asasekiryu. Matsuda is a retired sumo wrestler, once known as Mitsuru Ichinoya.

A sumo wrestler's day begins around 5am with morning training. They peel themselves out of bed and go directly to the training room. Working out on an empty stomach has its advantages in the effort to gain weight, Matsuda says, as this helps slow down the body's metabolism and makes burning calories more difficult.

At around 11am, the wrestlers take their first feast of the day. The veteran wrestler cook, Chankocho, and the young trainees in charge of the kitchen prepare chanko -- the staple diet of sumo wrestlers. This blanket term for sumo diet chanko comes from chankonabe, a one-pot stew.

Practically anything can go into chankonabe. Many different meats, vegetables and fish are cooked in the boiling chicken broth soup base. Chankonabe is very rich in protein and usually served in large quantities with other side dishes.

"You can’t move quickly with full stomach. Sumo training is more intense than you ever imagine. This is another reason of skipping breakfast."— Tetsuhiro Matsuda, manager of Takasago Sumo stable

"The practice of eating chankonabe dates back to the Meiji era. Chanko is easy to prepare and serve for a large number of sumo wrestlers at once and cost efficient. We eat more salads or side dishes along with chankonabe in Takasago stable, compared to other sumo stables," Matsuda said.

Chowing down

By fasting overnight and before morning training, sumo wrestlers switch their bodies to a fat storing mode when all the dishes are served on the table. Sitting in a circle, they are ready to dig in. Matsuda recalls some wrestlers who eat five kilograms of meat or ten bowls of rice in one meal.

For the skinny wrestlers, however, gaining weight can be an arduous process. They just keep gorging large meals until they throw up -- a famous part of the sumo wrestlers' harsh diet training. Thinking back on early days in his career, Matsuda said he used to try so hard to finish three to five bowls of rice at the minimum, per meal.

Right after eating the first meal, sumo wrestlers go back to their own bedrooms and take a long nap in the afternoon. It helps them to gain weight as all the food is being stored as fat. Then the giants come back again to the dining table around 6 or 7pm.

But doesn't eating massive quantities of food in order to get fat while working out to build muscle seem contradictory and unhealthy? "The answer is a lot of exercise," Matsuda says.

If you want to try out chankonabe, you are recommended to visit the Ryogoku Kokugikan Sumo Stadium (Yoko-ami 1-3-28, Sumida-ku) during the Hatsu Basho Grand Sumo Tournament. The chanko stall is on the second floor of the annex building and a bowl of chanko is only 250 yen. Don’t worry: Chankonabe is an extremely healthy meal in its own right. You won't gain weight -- unless you are planning to eat vats of it like the sumo wrestlers.

About the author: Monami Yui is a freelance writer and also a current master's student of journalism at the University of Hong Kong. Born and raised in Tokyo,  she is a world citizen, having lived in the U.S., Mongolia, Canada, France and Hong Kong. She holds her bachelor's degree in anthropology and cinema studies from the University of Toronto. For more information, visit ymonami.wordpress.com.

Monami submitted this piece as part of CNNGo’s CityPulse section. To find out what other stories we are looking for, go to our CityPulse page.

Want to share some insight on you city's sports players? Let us know: editor@cnngo.com.