The thing about building muscle, cutting fat and otherwise getting in shape is, well, you have to work out. No fair, right? But what if someone — or something — else could do a lot of the work for you? Such is the commonly perceived promise of electrical muscle stimulation training, aka EMS, a type of technology that activates your muscles from the outside while you activate them from the inside.
“It’s an efficient workout,” says Jackie Wilson, a lawyer-turned-personal trainer who founded NOVA Fitness Innovation, a network of boutique fitness studios in New York City that offers one-on-one EMS training sessions.
While the specifics vary depending on the model of equipment itself and the type of supervision you’re under, in Wilson’s studios, the training involves wearing a wetsuit-like outfit embedded with 20 electrodes that sit atop major muscle groups like the pecs, biceps and quads. As clients go through a body weight or lightly weighted workout — say, a circuit including squats, pushups and jumping jacks — he or another trained staff member uses a wireless device to send impulses of varying intensities to those muscles that are contracting.
Those impulses, which feel like intense vibrations that are neither comfortable nor painful, cue the muscles to involuntarily “micro-contract” up to 40 times per second, which is 20 times more frequent than most people can willingly contract their muscles, Wilson explains. As a result, you can work your muscles far harder than you could sans technology in one-third of the time, burn 700 calories on average in about 30 minutes and reduce the need for heavy weights that can strain your joints and lead to injury, says Wilson, who launched his first EMS studio after learning that European athletes had been using the technology for years.
Today, studios offering the technology either in one-on-one sessions or in small groups are sprouting up in cities across the country from New York City to Nashville, Santa Monica, California and Boulder, Colorado. Models, elite athletes and celebrities the likes of Heidi Klum and Usain Bolt credit it for helping them achieve athletic feats and body composition goals. Is it too good to be true?
From Rehab to Studio
EMS itself is nothing new. “The technology has been around for a while — mostly used in rehab hospitals and professional athletes,” says Dr. Jason Dapore, an osteopathic sports medicine physician in Columbus, Ohio.
For rehab purposes, the technology makes sense: It can activate and help maintain muscles that would otherwise atrophy after a surgery or injury. For example, Dapore explains, “the quad muscle after knee surgery can go dormant,” and that’s a problem because it’s needed for knee extension and to fend off post-operation stiffness. It makes sense, too, that professional athletes might use the technology, which isn’t cheap and hasn’t generally been accessible to the average Joe, in an attempt to gain a competitive edge, Dapore says.
But now as EMS becomes more available — and promoted — to the average Joe, its benefits are less clear. After all, the research showing its strengthening benefits are in weak or injured populations, not those who are already fit, Dapore points out. “If you take an unfit or weak body; it’s going to respond to anything you throw at it,” he says.
Fit folks looking for serious muscle gains may be disappointed in part because the technology skirts the central nervous system — a necessary muscle-building component, Dapore says. “If you’re looking to get shredded and really have awesome body composition by summer, this probably won’t get you there,” says Dapore, noting that no research has shown it can grow significant muscle. “Just because a machine is contracting your muscle at 100 percent doesn’t mean you’re getting stronger than if you were doing a good solid back squat.”
What’s more, it’s not as directly functional as many other exercises, Dapore points out. While long bike rides, for instance, can give you more steam to chase your kids and kettlebell work can improve your ability to hoist a suitcase into an overhead bin, wearing an expensive vibrating suit doesn’t so obviously translate to everyday gains.
Even Wilson is the first to emphasize that the technology alone, which costs between $110 and $150 per half-hour or less session at his studios, won’t transform your body overnight. “This is no shortcut,” he says. “It’s streamlining the workout and making it more efficient.” Wilson recommends using it as a supplement to other strength and cardiovascular exercises and building up to no more than three times per week (though you likely won’t want to since the post-session soreness can be staggering).
There are risks, too, the most likely one being overtraining, since you don’t feel like you’re working out as hard as you actually are. “It can sometimes take your body a little time to realize just how much it’s worked out,” Wilson says, and if you don’t allow proper recovery time, your fitness can backslide. More serious is the small risk of rhabdomyolysis, a condition that can be caused by any intense physical stress on the body, points out Alexander Erlikh, an exercise physiologist in New York City who tried EMS in a group training session about six months ago. The condition causes muscle tissue to rapidly break down and can overwhelm the kidneys with muscle cell byproducts. Though rare, it can lead to fatal kidney failure.
EMS is also ill-advised for anyone with a pacemaker, and may be risky for anyone with a heart condition, even one that’s unrecognized, Erlikh adds. The key to a safe session, he and other experts say, is working with a trainer or other professional who understands your health history, risks, fitness level and any lingering or threatening injuries. “If your hamstring isn’t completely healed or if you have a partial Achilles tear, this type of device can make it worse,” Erlikh says.
So Who Would Benefit?
That’s not to say the technology is useless or doesn’t hold promise for anyone. EMS training may be most beneficial to people who are relatively out of shape or sedentary, Erlikh and other experts say. “If you work in the office and don’t regularly work out, there’s a good chance your lats and glutes aren’t as active as they could be, and that could hurt your posture,” he says. In that case, EMS may help by increasing your body awareness (ever felt your left gluteus medius on fire?) and “enhancing your ability to make certain muscle groups fire up,” he adds. EMS can also begin to build strength in novices without risking the same injuries that an unsupervised heavy weight-training session carries for someone with poor form, Wilson says.
For folks who are already in good shape, EMS may help identify and correct minor muscle imbalances, Erlikh says. Dapore suspects the technology could also be helpful in a warmup or recovery session, or help keep certain muscle groups active while recovering from an injury. “Try it for a period and see how you respond to it,” he suggests, “but you shouldn’t look at it as a shortcut to hard work.”
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Is EMS Training the Missing Link to Your Dream Body? originally appeared on usnews.com