In a discovery that should surprise no one, medical experts are saying that a viral phenomenon known as the “skull-breaker challenge” could prove deadly to its predominantly teen participants.

For the thankfully uninitiated, the viral stunt originated in Spain, where three students were filmed jumping next to each other as the two bookending buddies kick the middle guy’s feet out from under him.

Go figure: The harebrained act sends the victim toppling to the ground, landing on their back and hitting the back of their head in the process. For whatever reason, the “skull-breaker challenge” took TikTok by storm, resulting in injuries across the US.

Doctors have condemned the practice for its potentially fatal outcome, reports Yahoo News. The “skull-breaker challenge” can cause a host of “serious and life-threatening injuries,” ranging from “skull fracture to paralysis, and death,” according to Nathan Richards, MD, an internal medicine and pediatrics specialist at the Ohio State University Wexner Medical Center.

Denise Klinkner, a pediatric surgeon at the Mayo Clinic in Minnesota seconded Richards’ statement to Yahoo News. “In spite of knowing this is the intent, the falling teen rapidly lands without blocking the fall, leading to at minimum a concussion,” she says. Klinkner adds that “an outstretched hand to block the fall may lead to a broken wrist or arm.”

It’s no surprise that the hazardous stunt is primarily practiced by youths, because the area of the brain responsible for impulse management is still developing when you’re a teen. As a result, youths are more likely to “engage in socially rewarding behavior and gravitate toward thrill-seeking, without focusing on potential risks or consequences,” says Sabrina Sykes, a psychologist at Ohio State’s Wexner Medical Center.

When coupled with TikTok, this lack of inhibition can prove to be a dangerous cocktail. Social media “offers instant popularity among peers in the form of ‘likes’ and ‘followers,’ ” says Sykes.

Unfortunately, the skull-breaker challenge isn’t the only potentially fatal stunt circulating the interwebs. The TikTok Penny Challenge — the practice of sliding a coin behind a partially plugged-in phone charger — has been slammed by firefighters as a fire hazard.