The massage gun trend is a relatively new one in fitness. You’ve used foam rollers before, and vibrating foam rollers appeared on the market three or four years ago. The theory behind these foam rollers was that the vibrations confused something called the Golgi tendon response, which would help to relax tight muscles.
The massage gun generally looks something like a power tool, and once it’s turned on, it whirs like one too (although recent models have quieted that). To use it, you simply aim it at your skin, about an inch away, and let it pulsate back and forth, relaxing muscles and promoting bloodflow in much the same way a vibrating foam roller does. It’s easier to use than a foam roller though, and more natural.
In theory, massage guns also offer a chance to modulate pain. What about pain modulation? Well, the pain you feel typically manifests as a specific frequency. Healthy nerve impulses should react to pain in milliseconds, but at certain frequencies, your pain may not be able to keep up with that. So in theory, a massage gun vibrating at the right frequency may “trick” the nervous system into blocking pain. We call this the “pain gate theory”.