When Shuhei Mainoumi became a sumo wrestler in the early 1990s, he only met the strict height requirements by injecting silicone under his scalp to appear taller.
Mainoumi would not need such a painful ruse today. The Japan Sumo Association has in recent years eased its height and weight standards to encourage applicants. In June, it trimmed the minimum height from 167cm to 165cm - a level that the relatively diminutive Mainoumi would have passed with ease.
Yet the efforts are still not enough to encourage young Japanese to choose a career in what is considered the national sport. Only 56 young trainees applied to join sumo stables this year - about half the recruitment levels from a decade ago, and far too few to make up for the 115 wrestlers who left the sport in 2011.
"There are very few young people joining. It's a big problem for sumo," says Mitsue Ishida, a sumo fan who travelled from central Japan to watch the November tournament in the southwestern port city of Fukuoka.
It is not hard to find reasons for lack of enthusiasm. The last few years have been disastrous for sumo's reputation, with a series of scandals including the death during a hazing of a young trainee and revelations of widespread bout-fixing.
Attendances are down, with ranks of empty seats cooling the atmosphere of the tournament in Fukuoka. Early in the 15-day tournament, the competition hall appeared only a third full even at the climax of the afternoon's action.
Some fans blame the declining audience on a dearth of homegrown talent at the top of the sumo table. Despite limits on the number of foreign wrestlers that stables can take on, both the current yokozuna grand champions are Mongolian, and only two of the five wrestlers at the second highest rank of ozeki are Japanese.
Veteran fan Koji Fushitani speaks for many in the ageing audience when he says the success of foreign grapplers is a symptom of wider social softening.
"Now that Japan is prosperous it has lost the hungry spirit . . . the foreigners have more guts," says Mr Fushitani, who grumbles that the sport has lost much of the appeal it had when he started watching bouts in the "days of black and white TV".
"Now that there are more foreigners, it's less interesting since they just use big size and strength to win. In the old days, Japanese wrestlers were smaller so they had to rely on technique rather than weight," he says. "These days sumo is cruder."
But not everyone is so disparaging. Many at the Fukuoka tournament were as happy to cheer foreign fighters as locals, and some credit foreigners with enriching sumo techniques. The slimmest current competitor is a Czech who has in the past defeated Japanese opponents more than 100kg heavier.
Daiichi Koba, captain of the Kyushu Institute of Information Sciences' student sumo team, names the Mongolian yokozuna Hakuho as his model. "He is the strongest and the best to watch," explains Mr Koba, with proper sumo terseness.
The rise of foreign wrestlers has also won sumo new audiences abroad and adds to the appeal for visiting tourists. One group of Mongolian fans, customers and guests of a Japanese construction company, proudly waved a national flag in the Fukuoka stadium.
"Every tournament [is broadcast] on Mongolian TV . . . for Mongolian citizens in Mongolian language," enthused Enkhjargal, a tour member who like many Mongolians goes by a single name. "In the near future sumo could be one of the Olympic Games."
The very idea of Olympic participation would shock purists who stress sumo's roots in the rituals of Japan's native Shinto religion and who delight in such cultural features as a referee uniform that is the court costume of a 14th century nobleman.
Former wrestler Kenjiro Goto, who runs a restaurant serving the chankonabe stew that is the sport's default diet, says one future road for sumo would be to stress its spiritual aspects and worry less about commercial success. But in the meantime, he suggests, one way to attract trainees would be to introduce a salary system.
Currently only the more successful wrestlers get paid a substantial wage, while most get only bed, board and pocket money. Lack of income adds to the risk of investing years in a sport where health problems are numerous and early retirement assumed.
"Parents worry about what will happen to their children if they go into sumo," says Mr Goto. "If they don't succeed in it, what will they do afterwards?"