It probably wasn't what Jane Fonda had in mind when she pioneered the home workout craze: fitness advice from grossly overweight men whose training regime includes taking a nap after a huge lunch.

But in their latest effort to fight the flab, overweight Japanese are turning to the behemoths of the sumo ring, who have released a DVD of simple exercises they claim keep them supple and, yes, fit.

Sumo Health Exercises features professional sumo wrestlers, including the 140kg (22 stone) Hokutosho, demonstrating 12 sets of stretches, squats and splits.

Despite their impressive girths, sumo wrestlers are fitter than most people think. "For their size, many wrestlers have a low fat ratio. They're professional athletes, after all," Hideki Yazaki of the Japan Sumo Association told Associated Press.

The association says the exercises strengthen the back and legs, and can be performed by children and adults alike. "They're fun, so we hope parents can get kids to do them instead of playing computer games all day," Mr Yazaki said.

The DVD demonstrates the squats performed before each bout, as well as a ceremonial move that involves raising an outstretched leg sideways while using the other leg to balance.

But the sumo route to health is not all hard work. The DVD includes a recipe for chanko nabe, a meat and vegetable stew that wrestlers tuck into after morning practice and before that nap.

The DVD could boost the ancient sport's popularity, which has suffered of late in part due to the absence of a homegrown yokozuna or grand champion.

Asashoryu, the current sole yokozuna, is Mongolian and the most popular wrestler on the circuit, the relatively svelte Kotooshu, hails from Bulgaria.

The 13 Europeans in professional sumo have brought a touch of showmanship to the otherwise staid sport. Attendance has slumped since the Japanese brothers Wakanohana and Takanohana, both now retired, packed out venues in the 1990s.

Last month the Russian wrestler Roho was given an unprecedented three-day suspension after being hurled into the third row of spectators. Rather than take defeat on the chin, as sumo convention requires, Roho glared at his opponent, smashed a glass door panel in the bathroom and assaulted two photographers.

His outburst prompted a backlash in weekly news magazines, some of which suggested foreign wrestlers were only interested in money and were ignorant of the sport's traditions.