Can that actually work?” It’s a question you could reasonably ask yourself when you consider electronic muscle stimulators, aka EMS. The short answer might be: It’s complicated.
These devices deliver minor pulses of electricity to your muscles, causing them to contract the same way that physical movement would. They’re safe and effective, according to the Food & Drug Administration, but that doesn’t necessarily mean they’re going to give you same results as an intense fitness routine would. And with an ab stimulator recently getting approval from the FDA to be sold on the market, it becomes important once again for consumers to manage their expectations.
When the FDA gives its approval to a medical device, such as a programmable pacemaker, or in this case, an EMS, it’s because the device is safe and effective. When used properly, it’s not a high risk to your health and safety, and it will fulfill the medical purpose it claims it will.
Many EMS devices are approved by the FDA, but only one ab stimulator, Slendertone Flex, made by BMR NeuroTech Inc., was approved as recently as January 2024. Ab stimulators are unique among EMS devices because they are designed specifically to target your abdominal muscles, unlike other EMS devices used by medical professionals in clinical settings to do things like treat muscle spasms or improve range of motion. The FDA’s approval of Slendertone Flex gives a jolt to the conversation about what EMS can do—and what it can’t.
If Slendertone Flex is FDA approved, does that mean using this over-the-counter device can give you a six pack? And is there a chance that other ab stimulators could soon get the same approval from the FDA?
Here’s the reality: Yes, an ab stimulator will strengthen your abdominal muscles, but it will likely not be so significant that you see any noticeable change. As the FDA itself states on its website, “Stimulating muscles repeatedly with electricity may eventually result in muscles that are strengthened and toned to some extent but will not, based on currently available data, create a major change in your appearance without the addition of diet and regular exercise.”
To see your muscles, you would have to strengthen your abs enough for them to grow in size and decrease your body fat. The National Academy of Sports Medicine says that abs only become visible on women below 19 percent body fat and on men below 9 percent body fat. That’s very low but still healthy—once a woman’s body fat drops below 16 percent and a man’s drops below 6 percent, they are in the unhealthy range.
Most experts agree that the best way to strengthen your abs is through core workouts, such as planks and crunches. A healthy diet and an exercise routine combining aerobic activity and strength training can help you lower your body fat.
Then there’s another final point to keep in mind. If a particular device hasn’t been approved by the FDA, there’s likely a good reason for it. Some non-approved EMS devices have caused shocks, burns, bruising, and skin irritation, or they might even interfere with pacemakers and defibrillators. Even if they aren’t dangerous, there’s no guarantee they’re going to do what they claim they’ll do. It’s not worth risking your safety while taking a shortcut to “better health.”
