(CNN) — For first-timers in a bathhouse in South Korea, stripping naked and soaking for hours in tubs with strangers often comes as a jolt. The scrub corner in any jjimjilbang (a Korean facility that's a bathhouse, sauna and spa rolled into one) is the section newbies find most alarming. This is because the scrub corner traffics in a completely different kind of naked intimacy -- one in which a grumpy Korean woman in black lace underwear uses a coarse towel to scrub every corner of her guest/victim's body.
For most, it's a punishing, yet oddly satisfying experience.
It lasts about 40 minutes -- or a few minutes longer than you'd find yourself in the ring for a championship prizefight.
Good Korean scrub
Don't worry -- they're not talking about you. Probably.
courtesy Dragon Hill Spa
The intense Korean cleansing process (called "seshin") entails soaking the body in hot water, then rubbing it with a "Korean Italy towel" -- a colorful, thin loofah with a sandpaper-like texture -- to rid the body of all the gunk, dirt and layers of dead skin that accumulate naturally.
Rolls of dark, gray skin fall away as the ddemiri (scrub mistress) works away, revealing soft, pink layers of skin underneath.
It's an extraordinarily rejuvenating -- and, again, painful -- process that locals embrace as a weekly ritual with family and friends.
Men and women have separate bathing areas and get scrubbed by members of their own gender.
Gaining traction
Korean scrubbing rituals have typically been embraced by few Westerners -- assorted Hollywood stars have gone in for quick sessions in LA's Koreatown.
Otherwise, the technique is largely unknown.
Over the past year or so, however, according to Seoul's Dragon Hill Spa head of public relations Hyun-Kyu Sang, the number of foreigners coming for scrubs is increasing.
"We've been noticing tourists coming to (South) Korea and staying two nights at a hotel, and one night here, at the spa," says Sang, explaining that many foreign visitors opt for package deals that included a seshin option.
"A lot of tourists come to (South) Korea and come here first, with their luggage, and get scrubbed to start their visit," he says.
Is the Korean-style scrub on its way to becoming the next global beauty trend? If it is, we want to be among the first to check it out.
That's why we went to Seoul to ask the best scrub mistresses for tips on getting the most out of a scrub session.
What to do -- and not do
1. Don't touch the shower gel
While many bring their own fancy shower gel to the bathhouse to lather up before the scrub, it turns out that bar soap, not the liquid kind, is actually the way to go.
"Use the soap provided by the bathhouses during the pre-scrub shower and soak," says Kim Jung Yeol, who's been a scrub mistress at the Dragon Hill Spa in Yongsan, Seoul, for more than a decade.
"If you use body shampoo, the skin gets too slippery to scrub properly, and the 'dde' (dead skin rolls) doesn't come off nearly as well."
2. Soak for 30 minutes in medium-hot water
We know, it's hot, but stay in a little longer. Your dead skin will thank you.
Courtesy Spaland
Impatient scrubees bolt out of soaking tubs after five or 10 minutes. Korean grandmothers stay in tubs seemingly for hours. But the optimal length for a prescrub soak is 30 minutes.
Soaking in hotter water causes the skin to wrinkle faster (a good thing), but according to a gaggle of ddemiri (scrub mistress) at Geumgansan Sauna in Hapjeong, customers should stay in the water temperature they're most comfortable with, instead of attempting a hotter tub and calling it a day after a few minutes.
"Staying in the water to prune is most important," says one ddemiri.
3. Be completely bare
This one may seem obvious, but scrub mistresses say many of their customers come to them without removing everything. This includes rings, earrings, glasses and other accessories.
Those with long hair should bring their own hair-tie -- the ddemiri will tie their hair in a perfect bun.
4. Seriously, relax
"Relax!" is the instruction issued most often by the ddemiri.
If the body is too rigid, the scrub mistress can't contort it into the positions necessary to get at every nook and cranny. It's awkward and painful at first, but forcing the body to relax its muscles allows the ddemiri to get things done most effectively.
"Usually customers listen and then they end up having a lot of fun," says Jung.
5. The fun should come afterward
This one surprises locals as well as foreigners.
Though some think sitting in a spa's various hot rooms before a scrub is an effective way to get the skin ready, ddemiris advise getting scrubbed before relaxing.
"If customers get scrubbed first and then go to the hot rooms, they'll feel more refreshed, since the sweat isn't blocked by dirty pores," says Jung.
"Then all they have to do after is rinse off in the shower."
6. Scrub weekly
Scrubs should be booked no more than once a week. Any more often and there's danger of overexfoliation.
But according to Jung, weekly scrubs improve skin vibrancy and blood circulation, as well as muscle relaxation.
Two places to get a good scrub:
Dragon Hill Spa, 40-713 Hangangro 3-ga Yongsan-gu, Seoul; +82 2 797 0002; open 24 hours; ₩11,000-₩13,000 ($10-$12)for admission, scrub prices vary. Spa Land, Centum City, 35 Centumnam-daero, Haeundae-gu, Busan; +82 51 745 2900; open daily, 6 a.m.-midnight, admission: ₩12,000 ($11) on weekdays and ₩14,000 ($12) on weekends; scrub starts at ₩20,000 ($18)