SAPPORO – “Bedrock bathing” on warmed slates is rapidly becoming popular in Hokkaido, attracting health-conscious women who want to sweat the weight off.
But the boom is also inviting dubious boasts the activity can provide such benefits as warding off cancer.
The style of bathing is spreading mainly in Sapporo, where at least 130 such bathhouses are concentrated out of the roughly 300 around the nation.
“Unlike in a sauna, you don’t have to endure (heat for a long time) to sweat, and it is good for your health and diet,” a woman said.
A bathhouse owner in Hokkaido said, “We would like to make it another (nationwide) boom from Hokkaido, like Mongolian mutton barbecue and curry soup.”
Bathers wearing indoor clothing lie on slates of black silica and other mineral rocks that are heated to 45 degrees via hot water pipes.
The bathhouse temperature is kept at about 40 degrees, with humidity between 50 percent and 70 percent. After 10 to 20 minutes lying on the slates, bathers take a break and drink water. This process is generally repeated three times.
“You can sweat naturally with far-infrared rays from warmed stones, improving the circulation of your blood,” said Tetsuya Sakurai, who runs two bathhouses for women in Sapporo.
“It feels good, as we sweat a lot,” said a 32-year-old female assistant nurse who goes to one of Sakurai’s bathhouses once or twice a month. “It’s also good for my skin. About 30 percent of my colleagues go to such places.”
A Sapporo municipal official said the registration of such bathhouses began to increase sharply last year.
Bedrock bathing is believed to have originated in the Tohoku region.
“I learned about bedrock bathing at a ryokan in the city of Kesennuma” in Miyagi Prefecture, said the owner of Hokkaido’s first bedrock bathhouse, in Date.
The innkeeper said his bedrock bathhouse was inspired by the health method technique of lying on rocks warmed by terrestrial heat, as practiced at the Tamagawa hot spring in Akita Prefecture.
Many bedrock bathhouses in Hokkaido are for women only, but some are open to men.
Recently, an increasing number of bedrock bathhouses have come to offer aesthetic treatment and massage services for an added charge.
Industry sources say bedrock bathhouses have investment growth potential, in part because they don’t require a lot of indoor space.
An official at Sapporo-based Hayashi Construction Industry Co., which builds bedrock bathhouses, said, “We’ve already received orders from nursing-care homes for elderly people.”
However, one problem has emerged: misleading and unsubstantiated claims. Some bathhouse operators are advertising that bedrock bathing is effective in treating cancer.
“To keep the bedrock bathing boom from being just temporary, the whole industry will have to pay attention to the representation of its effects,” an industry executive said.