I'm pulling into the Ski Basin parking lot feeling light and energized—not at all like I just powered 15 miles and 3,400 feet up a mountain on a bicycle for the first time.

My friend Tanya and I are laughing and planning what to cook for dinner and, in the back of my mind, I'm gloating a little, like I got away with something. Because Tanya is an accomplished cyclist, but I'm not. Cycling for me usually means moseying around at sea level, checking out antique stores. But lately, I've been performance-enhancing. Not with drugs, but with something that I've definitely become addicted to—kettlebell workouts.

Kettlebells aren't new. The cast-iron balls with handles have been around for hundreds of years. The Russian military used them to train soldiers in the early 1900s. But new research, and anecdotal stories like mine, suggests that the weights—which are designed to be slung around in the style of old-fashioned strongmen—can deliver aerobic, circulatory, flexibility and strength benefits far beyond traditional dumbbell workouts.

A recent series of studies conducted in Denmark shows that the combination of weight and cardiovascular training imparted by high-intensity kettlebell workouts can actually raise one's V02 max: the metric (previously thought to be genetically determined and unalterable by training) used by athletes to measure their maximum potential for oxygen consumption under severe aerobic stress.

The metal balls were introduced to the US in 2001 when former Russian special forces trainer Pavel Tsatsouline began training American military personnel and mixed martial arts fighters with these weights. His books and videos inspired a cult of enthusiasts to endure grueling workouts, develop an international kettlebell-instructor certification program and adopt a dorky
pain-centric lingo in which trainees are called "victims."

An entry-level kettlebell workout consists of exercises like the deadlift press and swing, which both start in a modified squat position, using a 16- to 35-lb weight. The "victim" shoots the bell upward into one of the prescribed positions (which I'm not going to describe here since you shouldn't do this without proper instruction) by tightening the abs and buttocks and popping the hips forward, all in a single, smooth motion. String a bunch of these together in quick succession and you're left jelly-legged and heaving like an asthmatic…which may explain why kettlebell training hasn't gone mainstream: It's really freaking hard. 

Early on, fighters saw similarities between the thrusting movements required to hoist kettlebells and the explosive hip action required in kickboxing and grappling, and began to integrate the bells into their training routines. But as kettlebells have become more popular, physiologists have discovered that these same motions are useful for pretty much every activity humans do.

In 1983, Russian physiologist Voropayev published a study in which two groups of college students were observed over the course of three years and underwent a standard battery of armed forces physical training tests. The tests were pull-ups, a standing broad jump, a 100-meter sprint and a 1k run. The control group followed a university physical education program that emphasized these activities, while the experimental group just lifted kettlebells. The results of the study are surprising: Even though they hadn't trained in the sports tested, the kettlebell group showed better scores in every exercise.

And this is where this story circles back to me and my triumphant bike ride. Here in Santa Fe, kettlebell fever is spreading fast, thanks to my friend Keira Newton, a petite and totally ripped Russian Kettlebell Challenge certified instructor, who whipped herself into the best shape of her life shortly after her second pregnancy. I started training with Keira in early 2008—about when I realized I was jealous of her Fitness-magazine physique. The plan was simply to tone up for my wedding in June, but I discovered that the thrice-weekly kettlebell routine Keira recommended had several interesting side effects.

First of all, I was saving time. Kettlebell workouts are high-intensity but short in duration, which meant that instead of an hour of cardio machine drudgery, I was getting a killer fat-burning workout in just 30 minutes. And second of all, I was getting much stronger at cycling…without riding the bike. A spate of business trips this spring had me hustling back and forth from New Mexico to New York with little time for peddling, but as long as I got my kettlebell workouts in during the week, I saw improvements on each weekend ride. During one loop around Las Campanas, my bike-geek husband looked at his power meter and then looked at me like I'd grown another head.

"You should not be able to hold that many watts when you haven't been riding a bike," he said. "You've got a bigger engine than you realize. You could race."

Keira's other students have seen improvements in rock-climbing, track and field (she works with high school athletes at Desert Academy), trapeze (she trains several of the Wise Fool circus performers) and dance. In addition, almost everyone reports losing weight or dropping sizes.

"You can make kettlebell sport-specific for any discipline if you just train the same motions and muscle groups," Keira says. "You're just loading the movements with weight, which makes you more powerful." 

Keira has a background in Feldenkrais therapy and just completed her Russian Kettlebell Functional Movement Screening training, which means she can even tailor workouts to increase range of motion in clients who need rehabilitation.

"Most of us rely on patterns or habits and therefore use ourselves in a compulsive way because we don't know the other options," she says. "With kettlebell, you have to pay attention to yourself. It's flexible depending on how you use your body and you don't always use your body in the same way."

When I say I'm addicted to the kettlebell, I'm not kidding. I had to quit training for a while recently after a surgery and found myself unable to sleep at night. And I'm not alone—people fall in love with their bells. They name them, get tattoos of them and take them everywhere. Keira's husband, Mark, once packed his along on a road trip to Colorado and stopped along the way a few times to get out and do 20-minute workouts in the snow. This is the kind of mania that kettlebell fever incites. But Mark's behavior made me feel less crazy for lugging my 20-lb bell to the airport for a recent flight to New York. The man at the check-in counter lifted my bag to the conveyer belt and scowled at me, "What have you got in here, a lead weight?"

Well, no, it's cast-iron, actually.

Want to become a kettlebell addict?
Keira Newton
Dynamic Kettlebell Fitness
1600 Lena St. #D2, 505-501-0180