This article originally appeared on People.com.
What It Is: Electric Muscle Stimulation (EMS)
Who Tried It: Grace Gavilanes, PEOPLE.com associate editor
Level of Difficulty: 7/10
On a Thursday afternoon, I made my way to Midtown Manhattan’s Core Club — a hub for CEOs and celebrities (and other people who can afford the club’s $50,000 initiation fee) — where fitness guru Mo Elzomor works as a personal trainer. Elzomor boasts an impressive background in weight lifting and cardio, but has recently set his sights on the benefits of Electric Muscle Stimulation (EMS). I was eager to see what all the hype is about.
The EMS service, which is used in physical therapy, contracts muscles using electrodes — an important nugget of information that worried me at first, considering that I’d be doing planks, lunges and squats while connected to one of two EMS machines at the Core Club. The session lasts 20 minutes and claims to burn up to 500 calories, and it’s so intense that doing any more than two sessions per week is not recommended.
I was ready to channel Elzomor’s star clients, Alessandra Ambrosio and Real Housewives of New York City‘s Luann de Lesseps, among others, so I took a deep breath and watched Elzomor spray a water-based solution onto a vest and thick bands — both of which came equipped with electrodes. I slipped into the vest and strapped the bands around my arms, thighs and butt. Could I get electrocuted? I immediately thought. My concern was one Elzomor has heard before: “You won’t get shocked,” he assured me.
“Doing one dumbbell curl contracts one muscle at a time,” Elzomor told me as he pointed to his bicep, sensing my fear and skepticism. “But this machine does 85 muscle contractions at once.”
I was intrigued, not knowing how I would react to this new fitness trend. Once I was ready to begin the 20-minute workout, Elzomor turned the dial on the machine. I didn’t feel anything at first, which he said was normal since he wanted me to get accustomed to the experience before bringing it up a notch. After completing a few seconds worth of curls, crunches, planks, lunges and squats (each!), Elzomor gradually increased the intensity, which left me … laughing.
I couldn’t stop giggling! The sensation was literally electrifying. Yes, it was difficult to confidently follow through with moves while your muscles are contracting 85 times per second, but my body has never, ever felt like a phone on vibrate before, especially during a fitness class. And it turns out, all the laughter isn’t uncommon to Elzomor, who witnesses the exact same reaction in all his first-time clients.
As for how I felt after the workout? I was winded immediately after completing the reps, but the real soreness came the next day after I landed in Mexico for a week-long vacation. I walked like a duck for my first two days in Mexico City as the soreness crept up and eventually took over my glutes, biceps, thighs and abs. I was a fan.
I immediately texted Elzomor with the good news, and like any good trainer, he couldn’t be happier for me (and my sore bum).
Verdict: If I was able to dole out the extra $145 for another session, I would definitely be reserving spots each week. But Elzomor says he hopes to bring his EMS machines to the general public in the near future. I’ll be impatiently practicing my squats and lunges until then.