In his genre-defining 1984 sci-fi novel “Neuromancer,” William Gibson envisioned a future filled with “joeboys,” or “nearly identical young men,” whose arms and shoulders were “bulging with grafted muscle.”

In the cyberpunk trilogy’s universe, the grafts were a prominent type of biological body modification among corporate bodyguards to increase strength and appear more intimidating.

While the intention isn’t to get swole without ever hitting the gym, scientists in China say they’ve effectively turned the concept into a reality. As the South China Morning Post reports, the researchers developed a “self-exercising” muscle graft designed to be injected under the skin. They say it could give bedridden patients a fitness boost without ever getting out of bed. These “myografts” could also be a game changer for those suffering from conditions that result in muscle atrophy and other age-related conditions.

If the current frenzy over black market unapproved GLP-1s is any indication, though, we could easily imagine certain gym bros jumping at the opportunity to inject themselves with the muscles grafts. (As Gibson once quipped, “the street finds its own uses for things.”)

As detailed in a new paper published today in the journal Nature Aging, the researchers describe how these myografts — the result of subcutaneous injections of modified muscle cells — led to “mature, vascularized structures that self-contract continuously in mice.”

“Myografts improve whole-body muscle mass and function, and metabolic and regenerative outcomes in aging and obese mouse models,” the researchers wrote.

While we’re likely still years away from human trials, the scientists described their preclinical study involving mice as a “noteworthy step in this direction.”

The grafts could provide those with extremely limited mobility a way to take a major shortcut.

“In a sense, we’re distilling the best part of exercise out… and avoiding all the negative effects of exercise, whether it’s the stress on the heart or the stress on your joints,” Chinese Academy of Sciences’ Institute of Zoology professor and principal investigator Ng Shyh-Chang told the SCMP.

“It turns out that the people who need exercise the most are also the folks who cannot exercise the most,” Ng added. “So we need some way to mimic exercise to get them started, to get their basic health going before they can actually do the exercise that they need to do.”

Even better, the scientists found that the myografts could produce other “therapeutic proteins,” or myokines, such as growth hormones and even weight loss-linked compounds such as GLP-1s, which can “counteract bone or muscle loss without observed side effects.”

Instead of transplanting entire three-dimensional structures known as organoids, Ng and his team opted to start by first injecting the cells and have them “form the organoid slowly under the skin.”

Once injected, the cells self-organized into myografts that could contract spontaneously, mimicking the effects of physical exercise.

“It’s contracting non-stop, 24/7, so it’s persistently secreting the good beneficial factors into the bloodstream,” Ng told the SCMP. “The sheer amount of good factors it’s secreting exceeds what you can get from acute exercise for just one hour.”

The team claims that the growth of these grafts remains stable, meaning that the risk of tumor-like growth is low — but we’ll only know whether it’s truly effective, let alone safe, for humans once clinical trials take place, something Ng is actively trying to set up.

But to get there could take quite some time, as experts who weren’t involved in the study told Nature, and plenty of questions remain over the approach’s viability.

More on artificial muscles: Scientists Show Off “Wearable Muscles” You Can Strap on to Get Way Stronger