I Tried the Mood-Boosting Ritual That Kylie Jenner and Bella Hadid Swear By

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You might have seen Kylie Jenner's Instagram story earlier this year, showing a pair of flat stomachs in black swimsuit bottoms and declaring herself and BFF Stassie Karanikolaou "Cold Plunge Girls." And, if you’re anything like me, you thought "why would you ever?" Kylie wasn't talking polar plunge-style dips where someone dives into winter waters in the wild for charity, she meant soaking in an actual bathtub of concentrated ice water. Freezing water and not even a charity involved? It sounded like my personal nightmare.

Until I started hearing about the benefits of an ice bath—the makers of the tub Kylie used claim it can boost your energy, mood, and metabolism. Though non-charitable, these benefits piqued my interest. When I heard that it wasn't just Kylie and Co., but many celebs who've done it (Kevin Hart, Bella Hadid, Lizzo, Zac Efron, and Tinx, for example)—and that it had become such a trend in the physical fitness world that ice baths are slowly being introduced in gyms—I decided I needed to try it myself. So I took the plunge in the exact tub many celebs have at home, the Plunge.

I bravely strolled into Equinox Wall Street in a sweatsuit, fully prepared to catch hypothermia. The instructor, Senior Spa Director James Gu, gave me some slippers and a robe to put on over my bathing suit. Once I’d changed, he walked me through the proper breathing technique to keep me grounded (without hyperventilating) in preparation for the plunge: breathe in 4 counts, hold 4, exhale 4, hold 4, repeat.

The target amount of time to spend in the tub is two or three minutes, although pros last for as long as eleven. After soaking for all of 1 minute and 14 seconds at 48 degrees Fahrenheit, I tapped out—which isn't terrible, says Gu, who assured me many first timers don't make it that long. As I stepped out of the tub, my body just on the brink of numbness, I felt inexplicably present and, somehow, not at all cold. Instead, I felt an adrenaline rush, followed by a sense of relaxation. The experience left a lightness that relaxed all of the muscles in my body. I was significantly less tense than I had been pre-plunge (without even realizing how clenched up I was before). Did I suddenly… like the cold? As I thawed out in the infrared sauna, I asked the instructor dozens of questions, and he answered.

The way he tells it, the benefits of cold water exposure are not just skin deep. While plunging regularly can help improve skin radiance and tightness, it may also help boost circulation, metabolism, immune system, and mood, support better sleep quality and weight loss, and reduce bloating and stress.

Sold! I was ready to install a Plunge at home. Until I remembered that my apartment is tiny and that they start at $4,990, depending on size and features. You’ll want to think of it as more of a luxury investment, like having a jacuzzi in your backyard, since it does not double as a regular bathtub, as no plumbing is involved. You simply fill it up once with a hose or faucet and let the Plunge system pump the water through the chiller to keep it cold. That said, for a few grand more, you can upgrade to a Plunge that is both a hot and cold tub so you can get the best of both worlds for a lifetime.

Now, you may be asking, couldn’t you just use your own bathtub to take a cold dip? According to Gu, you technically could, but it wouldn't have the same effect. Filling your tub up with cold water and jumping in may chill you for a couple of minutes, but it wouldn't be as cold as the Plunge, nor could it stay cold for as long as you need it to in order to actually reap the benefits. The Plunge will stay at the temperature you set it to, plus its comprehensive filtration system — featuring an ozone filter, UV filter, and a micron water filter—will filter out any germs in the process so you benefit without festering in your filth. (Although, Plunge does recommend that home users drain and refill their plunge every three months or so.)

Not ready to dive in given that pricetag? Understandable! Try a few minutes in a cold shower or bath every day to build up to pro status. Who knows, maybe by the time you build up your stamina you’ll be ready to hit "Buy Now." Alternatively, hit one of these gyms or spas that have facilities where you can take the plunge.

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