• 06.19.17

It’s Now Possible To Hack Someone’s Muscles

An experimental technology called Wired Muscle has profound implications in everything from sports to rehabilitation. It’s not without risks, though.

Two hundred and fifty milliseconds. That’s how long it takes humans to see something, process it, and ignite our muscles to react. Knowing that, it seems like a minor miracle that any major league baseball player could hit a fastball at all, since it takes only 400 milliseconds to reach the plate.


But what if you could take our brains out of the equation entirely? What if you could connect the batter’s muscles with the pitcher’s muscles to complement one another’s movements? People could react faster. Almost five times faster, in fact, if they’re using Wired Muscle, a new technology developed by researchers at the University of Tsukuba in Japan and Sony Computer Science Lab. It’s a system comprised of electrical sensors and stimulators that connect the muscles from two different bodies, allowing them to be mirrored or even coordinated to work together. 

And the creepiest, most incredible part? Wired Muscle makes your body react involuntarily–as if you were a puppet, choreographed with invisible strings. “It feels like someone inside your arm is directly moving your muscle,” says Jun Nishida, lead researcher from the University of Tsukuba.

How could such a powerful technology be used? Take the baseball example. Wired Muscle could make professional athletes react faster to one another during play, but, perhaps more crucially, the best batter on your team could literally play puppet master to the worst batter on the team, too. This functionality could help people in rehabilitation walk again with more ease, and it could even teach people new motor skills, making the piano a much simpler instrument to master.

Nishida has been researching how electric muscle stimulation (EMS) can control fine motor coordination for years now. Last year, he developed a platform called BioSync. The device, worn on the arms of two people, measured one person’s muscle activity then duplicated the movement, involuntarily, in the other person’s arm. It could essentially mirror physical behavior without actually seeing it.

Now, in a newly published paper, that BioSync hardware has evolved into Wired Muscle. Rather than just mirroring movements between two people, it can coordinate them. The team demonstrated this through a simple drop test. A person dropped a baton while another person tried to catch it. Done without assistance, this is a surprisingly hard feat to pull off. The catcher needed that full 250 ms to make the catch. With Wired Muscle, it took just 60 ms. 


[Photo: University of Tsukuba/Sony Computer Science Laboratories, Inc.]
Technically, Wired Muscle measured the electrical impulses inside the dropper’s extensor digitorum muscle (think of that as the open-the-hand muscle). Once it measured the muscle activation, the system beamed that information to the catcher’s hardware, and used EMS to activate the flexor digitorum muscle of their arm (think of that as the close-the-hand muscle).

Of that Wired Muscle-enabled 60 ms reaction time, 10 ms was for the measurement and transmission of data, and 50 ms was for the human muscle to respond. It used technology to coordinate the movements of two people, breaking the limits of human perception and hitting the thresholds of human biology. 

[Photo: University of Tsukuba/Sony Computer Science Laboratories, Inc.]
The next steps in the research will involve connecting more muscles to the BioSync hardware, so that more complex motor functions can be measured and controlled. From there, “we envision that Wired Muscle will not only speed up the reaction of the human motion, but also it will accelerate and unveil the mechanism of motion skill acquisition,” says Shunichi Kasahara, joint lead researcher from the Sony CSL. That’s because even though the reactions someone makes within Wired Muscle are technically involuntary, researchers believe they “could be perceived as a ‘virtual’ voluntary action,” or basically, practicing a new skill with your body that you don’t have yet. 

The potential for acquiring new motor skills is profound. Imagine learning to golf by swinging with Tiger Wood’s form, from your first moment at the tee.

[Photo: University of Tsukuba/Sony Computer Science Laboratories, Inc.]
Even still, to automate our human reactions through bits of binary code feels strangely inhumane. There’s also a real security risk. “[For] now our devices are connected by a wire, but it can be by wireless LAN,” says Nishida. “If the communication path is hijacked by someone else, you will lose control of your body.” Read that again. You will lose control of your body. To a hacker, or whomever else wants it.

But even short of malicious intent, if we’re already plugged into another person, or even a machine, do we have free will anymore? Or are we just reacting to one another in the most efficient, prescribed way possible at any moment? 


“This is quite great question to consider,” says Kasahara. “For this significant discussion about automating human behavior or not, I think we should design the technology, which we call ‘Superception Technology‘, to allow us to preserve a sense of own ownership of our own action, and to maximize the use of residual human’s physical and cognitive ability . . . It is important to research appropriate assistive technology to recognize, predict, and actuate our body, and it then will not make us just an extension of the machine but make us ’empowered.'”

About the author

Mark Wilson is a senior writer at Fast Company. He started, a simple way to give back every day.