I remember asking my physiotherapist once—just as she hooked me up to a muscle stim machine (electromyostimulation or EMS)—if she thought it really helped recovery.
She looked me in the eye and shrugged, “To be honest, I really don’t know if it does much or not.”
“But it certainly doesn’t hurt,” she added.
Not exactly the biggest vote of confidence for the technology.
Muscle stim technology has been around forever in the physiotherapy world, where it has been used primarily for rehabilitation purposes. One of the predominant beliefs was that it can help prevent muscle atrophy after an acute injury.
More recently, though, people have come to believe it also helps with recovery, and even with building strength. While this might be a new concept to the western world, Russian athletes have been using it since the 1960s (Soviet sport scientists and coaches oversaw the use of EMS in elite athletes).
CrossFit athletes, who tend to be willing to try anything that promises to help their recover, of course, quickly hopped on board the muscle stim craze. It’s unclear whether they truly are noticing big differences in recovery and/or performance from EMS, or if it has just become trendy because of the multitude of CrossFit Games athletes, who posted about the magical new device Compex gave them.
And then the rest of the community blindly followed…
If Camille Leblanc-Bazinet says muscle stim works, then it has to work, right?
Muscle stim has grown so prevalent that today there’s a decent-sized market for at-home, portable EMS machines that anyone can purchase (for roughly $500 to $1,000). In fact, coach Tom himself bought a PowerDot muscle stim device last year, which I used when I was nursing my wounded foot back to health this winter. Verdict is still out whether or not it helped, but the vibrations sure feel good.
What exactly is EMS and does it work?
EMS involves producing muscle contractions using electrical impulses (current) through electrodes that are attached to the skin. The electrodes are placed on or near the muscles that are to be stimulated (the consensus is to focus on large muscle groups only).
The science goes like this: Essentially, the electrical impulses cause the muscles to contract by mimicking the action potential from the central nervous system. And there have been studies (involving untrained and trained/elite athletes alike) that seem to back up this science. One of the results is that it can help you build muscle.
In fact, in a review of 200 such studies, investigators at the Institute of Sport Science and Sport Informatics at German Sport University in Cologne, Germany found that EMS produced “significant gains in maximal strength, speed strength, power, jumping and sprinting ability.”
“Because of the clear-cut advantages in time management, especially when whole-body EMS is used,” the study review concluded, “we can expect this method to see increasing use in high-performance sports.”
But let’s slow down for a minute. It’s not exactly so cut and dry. Many of those studies either weren’t so conclusive, didn’t have large enough sample sizes, or failed to provide a direct cause and effect relationship between EMS use and muscle growth/improved athletic performance.
In other words, there simply haven’t been enough modern studies to prove, unequivocally, that EMS leads to these benefits. The technology, at this point, seems to be more of an art than a science.
For instance, no one seems to know why some athletes respond quite well to EMS, while others see no benefit whatsoever. With the increased interest in recent years, there will no doubt be further (and better) studies to come, but they’re simply not out there yet – at least not enough to come to any consensus.
Of the studies done to date, many actually show much more promise for EMS use in rehabilitation—everything from treating minor injuries, to knee or hip surgery rehab, to stroke recovery. In that vein, it would make sense that an athlete could benefit from EMS generally during workout recovery time. It has been suggested that using EMS at night, after a hot shower to loosen the muscles, for instance, can be of benefit.
But as for building muscle, strength and power? The jury is still very much out on whether EMS can help you with that.