This article by Jake Rossen was originally published in Van Winkle’s, the publication dedicated to sleep.

Walk into Steve Koepfer’s Sambo Academy in New York City, and you’ll find a wall covered with hand-scribbled signatures. Each has a name, date and brief description of the first submission hold that new students were able to apply in a “live” sparring session with an actively resisting opponent.

Of the 40 beginning martial artists to sign the wall since the school relocated to its present location two years ago, every single one lists the rear-naked choke as their inaugural technique.

Less blood is flowing and the brain, deprived of oxygen, powers down like a light with clipped wires.

“I think it’s in our genetics to recognize it as the main way to attack other human beings,” Koepfer says. “We know intrinsically the rib cage protects organs, that bones cover other areas, but the neck is exposed. The easiest thing to do is to wrap your arms around it.”

The choke — alternately known as the sleeper hold, the mata leon (lion killer) or by its proper but less romanticized word, strangulation — has become one of the most dramatic applications of suppressing aggression in modern popular culture. James Bond regularly fends off henchmen with a massive arm squeezing his throat. Professional wrestlers drum up crowd sympathy as they seem to drift off while in the hold. More recently, mixed martial artists have used it to provide one of the few definitive and inarguable conclusions to a prizefight. Anyone can get caught with a “lucky” punch — but a choke? A choke must be calculated and finessed, like a snake constricting its prey.

For a spectator, the choke speaks to deep fears of vulnerability; it approximates death and finality. For the recipient, it represents complete subservience; to be rendered unconscious is to be entirely defenseless. Politicized, it’s a metaphor for over-excited and under-trained law enforcement officers. In all cases, it’s an intimate way of exerting will over another individual.

“You’re going to sleep in a person’s arms,” Koepfer says. “Choking is really very personal.”

A BRIEF HISTORY OF THE HOLD

Incapacitation by oxygen deprivation has been around since the dawn of murder. In Pankration, the Olympic sport that began circa 648 B.C., combatants strangled opponents until they stopped resisting. When Jigoro Kano founded the sport of judo in 1882, he endorsed the technique of shime-waza, or clutching the throat in order to win a contest. It was the first time a choke was widely recognized as a technique, not a desperate criminal bid to overpower a victim.

As judo and jiu-jitsu began to travel to different parts of the world in the 20th century, professional wrestlers incorporated chokes into their ensembles. It was highly dramatic — the crowd’s hero in danger of slipping into unconsciousness before rallying for the victory — and a good way to give the wrestlers a rest by standing relatively still. Early wrestling star Verne Gagne, who died in April 2015, became renowned for his “sleeper” finish. Such legends of the sport as Roddy “Rowdy” Piper and Brutus “The Barber” Beefcake used it regularly too. The hold is ubiquitous in WWE; it’s common to see at least three or four during any given telecast of Monday Night RAW.

Infamously, Hulk Hogan applied the move to talk show host and actor Richard Belzer on live television in 1985. After challenging the integrity of wrestling’s outcomes, Belzer insisted his guest demonstrate his sleeper submission; Hogan’s massive arm engulfed Belzer’s slim neck, and the host fell to the floor, unconscious. He then popped up with a bloody forehead to introduce a commercial break. (A subsequent lawsuit against Hogan was settled in Belzer’s favor. It was, he once said, the choke that put a down payment on a home in France.)

Aside from professional wrestling and judo, choking someone generally led to an appearance on your local police blotter. As a result, pay-per-view customers who ordered the early Ultimate Fighting Championship events in the mid-1990s were stunned by their application. Royce Gracie, the lean Brazilian jiu-jitsu stylist who wasn’t much more physically intimidating than Belzer, found himself arguing with both his opponent and the referee when he used his canvas Gi jacket to strangle Ken Shamrock into submission. No one, including the audience, was entirely sure what had just happened.

As mixed martial arts — and the resulting explosion of jiu-jitsu academies —proved, it was relatively simple physiology. Picture two arteries, the carotids, running from the aorta in the chest and up through either side of the Adam’s apple. They supply blood to the brain. If they’re squeezed, their diameter narrows; less blood is flowing and the brain, deprived of oxygen, powers down like a light with clipped wires. Aggressors use their biceps, forearms, wrists and Gis to pinch the carotids like a drinking straw.

“By going unconscious, it forces your body to get horizontal,” explains Keith Hainey, a jiu-jitsu practitioner and former paramedic. “Blood gets pumped back into your brain more quickly. That’s why you sometimes see [other] people lift up the legs. That’s to get more passive blood flow to quicken arousal.”

(A quick note: Anything involving the carotids is a “blood choke” — a relatively benign and painless way to render someone unconscious. Air chokes compress the trachea or larynx and block the airway, creating a feeling of suffocation. Squeeze hard or long enough, and you might fracture the airway, Heiney says. This can mimic the injuries seen when throats hit steering wheels in car wrecks.)

Blood chokes are typically applied until the recipient begins to feel a sense of futility — their vision narrows, stars may appear and sleep is imminent. Depending on the person, that can take anywhere from a few seconds to nearly a half-minute. For some, one narrowed carotid is enough; for most, squeezing both is plenty. Lacking any escape, they’ll tap out. In some cases, however, loss of consciousness comes on so quickly that they may not have time to signal surrender.

Some feel like they’ve just taken a power nap. Others suffer a brief lapse in memory. “It’s like someone turned out a light,” Heiney says of the handful of times he’s gone out. On one occasion, “I didn’t even know it was coming. I was rolling to try and get out, and the next thing I know, people are holding my legs up.” The rest of the day was hazy.

Koepfer, who has practiced and taught martial arts for nearly 20 years, has seen many choke-outs and a variety of different responses. One student woke up on all fours growling like a feral animal. (“That was weird.”) Others reported dreams and even euphoria, likening it to taking a hit off a potent joint. Another flopped to the mat during a tournament, woke up and asked if there was going to be a tournament that day.

THE “ULTIMATE ASSERTION OF DOMINANCE”

David Ley has never been choked out. “I came really close one time,” he says, but tapped at the first sign of stars in his peripheral vision.

Ley, a Ph.D. and practicing psychologist, trains at the same Albuquerque, New Mexico gym as former UFC light heavyweight champion Jon “Bones” Jones and female contender Holly Holm. Professionals, amateurs and those looking to acquire self-defense skills congregate under one roof. Most eventually develop the self-confidence that comes with turning threats into lifeless lumps of flesh. It’s what Ley calls the “ultimate assertion of dominance” over another human being.

It’s the kind of power that is occasionally terrifying, even when you’re the one doing the choking. A couple of years ago, Ley was training with a friend who eventually found himself in an untenable position. Ley had secured a choke that restricted blood flow, but didn’t afford him a good view of the man’s face. By the time Ley realized he was out and let go, his friend had gone into something resembling a petit mal seizure.

“It scared the crap out of me,” he says. “I felt like I broke my friend’s brain.”

Both parties grapple with feelings of achievement, vulnerability and euphoria.

Once his friend was roused and unhurt, congratulating him, Ley had another sensation. “There was a certain sense of triumph, of accomplishment, of dominance.

This is the paradox of the choke. With two fighters spooning each other, a mess of entwined limbs, a natural camaraderie develops. This might possibly be traced to the release of oxytocin, the “love hormone” that creates feelings of warmth. When someone is put down by a submission, both parties have to grapple with feelings of achievement, vulnerability and euphoria. For some, it’s revelatory; for others, shattering.

Koepfer remembers when two of his students were tangled up on the mat. One was a retired cop, the other someone young enough to be his son. The cop found himself trapped in a choke and tapped to signal surrender. He sprang to his feet, angry. For a man accustomed to displaying authority, it was an unacceptable moment of vulnerability. He left the school shortly thereafter.

“The assumption of a choke is that once someone is out, you’ve asserted complete and total dominance over them,” Ley says. “And the implication is that you can do anything to them.”

Fortunately, most blood chokes are safe. The brain needs several minutes without oxygen for cells to begin to die off. Contrary to action films, it’s a rather arduous process to kill someone via strangulation. But that’s still no guarantee everyone who goes to sleep wakes up the same person.

THE DOWNSIDE OF DOMINANCE

Sean Entin managed amateur wrestler Mark Kerr at a time Kerr was stampeding through mixed martial arts. Kerr sunk only one choke in his career; most of his time was spent using a gargantuan, self-admittedly steroid-powered frame to outwrestle and throttle opponents.

Kerr’s athleticism waned, as did his interest in the sport. An entrepreneur, Entin saw MMA’s popularity dip both in Japan and in the States. Though he got out of the management business, he trained at gyms in California to stay in shape. “Lots of friends who were Navy SEALs were doing it,” he says. “I didn’t want to compete. But it was addicting, a great outlet to relieve stress.”

“The choke is the king of submissions.”

One day in late 2011, Entin was put in a choke during training. When he was released — he didn’t go completely out — he had the sensation something was different. “My glands were swollen. There was some numbness in my left arm.” In jiu-jitsu, nagging injuries, pains and protesting body parts are part of the schedule. Entin didn’t worry about it.

Six weeks later, he collapsed. Surgeons found his carotid was severely damaged and producing blood clots; one had traveled to his brain, triggering a stroke. Entin spent a month with a piece of his skull removed to accommodate the swelling. His life since has been a series of physical therapy appointments and constantly moving goalposts to return to normalcy. He walks with a limp.

After word got out of his injury, grapplers “lashed out” at him, he says, because they felt he was portraying jiu-jitsu in a negative light. Entin loves the sport and still counts many fighters among his friends, but feels the zero-risk portrayal of chokes in martial arts might be misleading.

“All I’m saying is, look, this is something that can happen.” Not tapping, which can be a matter of pride for some advanced grapplers, might pose unnecessary risks.

Heiney agrees. Though Entin was only 39 at the time of his stroke and complications can occur in any demographic, the biggest problem may be in older participants. “We build up plaques in the carotid just like anywhere else in the arteries,” he says, referring to the cholesterol that can lead to heart trouble. “If your carotid is congested, the plaque could break off and, in theory, cause a stroke.” Arteriovenous (AV) malformations, or defects in blood vessels, can also precede a worst-case scenario for choking-related injury.

“Cops today do not get adequate training. You have rookies…carrying weapons and trying to subdue someone.”

In Japan, where judo is so embroidered in culture that it’s taught in schools, curriculums have come under fire for haphazard safety regulations. The family of one student won a lawsuit in 2011 after he was choked unconscious, choked a second time and then tossed to the mat. He suffered a head injury that led to permanent cognitive impairment.

It is impossible to know if the addition of throws, strikes and other martial arts techniques that precede a choke could potentially increase the chances of damage. Unlike concussions in boxing or football, there is no research on what repetitive, short-term oxygen deprivation does to the brain.

Instead, the controversies over chokes typically appear after the kind of immediate, broadband incidents that have come to exemplify law enforcement. Fatalities that come as a result of police restraint are usually due to chest compression or an improperly applied technique that results in damage to the anatomy of the airway.

“Cops today do not get adequate training,” Koepfer says. “They do their cursory bit in the academy and never again. You have rookies who have never been in a fight in their life who are suddenly carrying weapons and trying to subdue someone.”

Several police departments across the country have banned choke holds, though their definition of one is often murky. The New York Police Department bans anything that puts pressure on the neck; Charlotte’s force acknowledges the difference between a blood choke and an air choke.

“A DEEPLY SPIRITUAL EXPERIENCE”

When sports debates turn to whether UFC women’s champion Ronda Rousey could beat Floyd Mayweather in a fight, no one argues that victory would come from Rousey knocking Mayweather out. The expectation is that she would use any number of submissions that negate Mayweather’s gender advantages. No matter how big or tough you are, everyone needs oxygen to the brain. The choke is the biggest equalizer in any physical confrontation.

“Break someone’s arm or ankle and they can still keep fighting,” Koepfer says. “Adrenaline, high on drugs, whatever the reason. Guys in grappling tournaments will get things torn and not tap out. You can make a decision not to quit. But a choke is the king of submissions. Someone is unconscious and you walk away. There’s no decision to be made. Your brain gives up.”

The recurring idea of Rousey beating Mayweather — a conversation about gender roles that would be irrelevant in most sports — is an indication the cultural attitude toward carotid manipulation has evolved considerably from the days of wrestlers using it as a theatrical device. It’s become a technique as valid as a right cross or zone defense while maintaining its reputation for being barbaric. Regardless of the science behind it, the sight of an athlete going rigid, eyes open but unseeing, is unsettling.

The respective role of the choke in self-defense, as an empowerment tool, and in spectator entertainment is similar. It reflects a very primal fear of death. To apply it means being able to deny becoming a victim; to survive it simulates the loss of control we all eventually face.

When Ley choked his friend unconscious, he stood by and waited for some kind of frustration or panic to materialize as the oxygen began to re-circulate. Instead, his friend seemed elated. Later, the two talked about it.

“He regarded it as one of the most powerful experiences of his life,” Ley says. “Like a deeply spiritual experience. He wouldn’t have changed it in the slightest.”

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