Brute Force: People can definitely take a beating (2024)

The human body can withstand a remarkable amount of punishment, as bones are made of one of the strongest materials found in nature. At the same time, even an unarmed person with the right training can do an astonishing amount of damage.

How much does it cost to break a bone? And how much chaos can one person cause? In an age where 'extreme fighting' has become a popular phenomenon, scientists are testing the extremes elite athletes can go to to help the rest of us.

"Comprehensionbrain damagemechanisms down to the cellular level will ultimately help everyone, not just athletes,” explains biomedical engineer Cindy Bir of Wayne State University in Detroit. “If someone sustains a brain injury in a fall or car accident, what we learn from athletes can also help.”

Bone is extremely strong – ounce for ounce, bone is stronger than steel, as a similarly sized steel bar would weigh four to five times as much. One cubic inch of bone can basically support a load of 19,000 lbs. (8,626 kg) or more – about the weight of five standard pickup trucks – making it about four times as strong as concrete.

However, whether the bone can actually withstand such loads depends greatly on how quickly the force is delivered.

“If you do CPR, you can give chest compressions without breaking your ribs, but if you use the same amount of force quickly instead of slowly, you can end up with broken ribs,” Bir explains.

Power released

When it comes to releasing force quickly, Bir and her colleagues studied boxers and found that they could generate up to 5,000 Newtons of force with one punch, more than what was exerted on the Earth's surface by half a ton.

When it comes to kicking, "they can obviously generate more force because there is more body mass behind them," Bir said. After looking at kicks from different fighting styles, they discovered that experts could generate up to 9,000 Newtons with them, which is equivalent to about a ton of force.

A quick, sharp blow that produces about 3,300 newtons of force has a 25 percent chance of breaking an average person's ribs, she said. It takes more force to break the femur, Bir noted — perhaps about 4,000 Newtons — because the long femur's purpose is to support the body.

“It doesn't mean you won't have a fracture below these values, or you will have a fracture above them,” Bir said. The amount of damage a blow inflicts also varies due to factors such as the amount of muscle or fat covering a bone and the angle at which the blow lands, as well as a person's age and health, which can affect bone strength.

While it makes sense that a huge fighter can throw more powerful punches than a lightweight, "it's also about how much of your body mass you can recruit," Bir said. “You see some little guys get hit with a lot of power because they know how to recruit their masses.”

Roll with the punches

When it comes toknock someone outwith a blow, "it's less about the force of the blow than it is about turning the head around, making it move in a rotating manner," Bir said.

The shearing forces of a blow that knocks the head back stress the neurons and the brain shuts down in a protective response. A punch that gives the head enough spin to go from 0 to 43,000 rpm in just one second has a 25 percent chance of knocking someone unconscious.

"That's why you see boxers build up neck muscles. The idea is that you can prevent those kinds of movements afterwards," Bir explained. "It's also about anticipating the stroke; the ones that catch you off guard can be a bigger problem."

Taking the wind out of someone's sails also has less to do with violence than with the impact that happens to make it happen, Bir said. When this happens, the air is not literally forced out of the lungs, but it is a matter of causing spasms of the diaphragm (the muscle tissue under the lungs).

“A stroke can cause your diaphragm to become temporarily blocked – it's like a spasm and therefore makes it difficult for you to breathe,” she explained.

Wading into battle

It can be difficult to examine how much damage someone can actually cause or suffer.

“We try as best we can to study athletes in their home environment, so to speak, so the more time in the ring, or during competitions, the better – that's when they really struggle to reach maximum potential, Bir said. . “It can be difficult to integrate equipment into the environment to measure them because you don't want to disrupt their normal function, such as sensors that could reduce the protective effect of their gloves. The good thing is that technology is evolving and becoming smaller and wireless, so as not to get in the way of what people are doing."

The data Bir and her colleagues were able to collect could help save lives.

“We joke that if someone is willing to get hit in the head, we should measure it,” she explained. “If we know what causes an injury, you can do simple things like developing better protective equipment and designing bicycle helmets to help seven-year-olds, for example.”

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