Ask Smithsonian: What’s the Longest You Can Hold Your Breath?

While some studies say most people can hold their breath for 30 seconds to maybe a few minutes at most, Aleix Segura Vendrell of Spain, the most recent Guinness World Record holder, held his for an astonishing 24 minutes and 3 seconds while floating in a pool in Barcelona.

Don’t feel ashamed if you can’t even approach Segura Vendrell’s pulmonary prowess. The ability to hold your breath is hardwired.

Segura Vendrell achieved the record with the help of what is known as an oxygen-assist. He breathed pure oxygen for a certain period of time before he began his extended float—essentially hyperventilating, filling his lungs to capacity with oxygen.

Lung function—and breath holding—varies widely from individual to individual, says Clayton Cowl, chair of preventive occupational and aerospace medicine at the Mayo Clinic in Rochester, Minnesota.

Body types and gender can influence lung function. For instance, studies have shown that people with shorter trunks tend to have lower lung function than those with longer trunks. Women have lung volumes that are 10 to 12 percent less than men, because their rib cages are usually smaller. 

During the normal breathing process, oxygen is taken in and carbon dioxide is exhaled. The process is automatic, occurring thousands of times a day. Holding the breath causes carbon dioxide, which is essentially a waste product, to accumulate with nowhere to go. The longer the hold, the more likely the person will experience strong and painful spasms of the diaphragm and in the muscles between the ribs as carbon dioxide builds up in the blood. The breath holder becomes lightheaded. High carbon dioxide levels—not low oxygen—account for the symptoms experienced by breath holding, says Cowl.

“It’s like a carbon dioxide narcosis,”—an almost narcotic-like state, he says.

The parameters of breath holding are primarily dictated by hard-wired processes, according to Cowl.  Chemical receptors in the brain’s medulla oblongata (a part of the brain stem) act in a manner similar to the thermostat for a central cooling system. When carbon dioxide reaches a certain level in the blood stream, the receptors “trigger the brain to say ‘I need to breathe,’” Cowl says.

Another innate process is the Hering-Breuer reflex, which helps prevent over inflation of the lungs. A deep breath triggers the reflex, causing certain stretch receptors in the lungs to fire. The receptors send signals to the brain’s respiratory center telling it to suppress breathing—because you’ve already taken a breath.

But psychology plays a crucial role as well. “You can voluntarily say ‘I’m going to hold my breath longer than a usual breath,’ and by doing so, you can train yourself to do longer and longer breath holds,” Cowl says.

That seems to be how people like Segura Vendrell, who is a diver, and other people who engage in free diving, appear to be able to hold their breath for especially long periods of time—four to eight minutes or more, even without breathing oxygen beforehand—while they descend to depths of up to 700 feet.

This is a trained voluntary response, says Cowl, but “on a cellular level, it’s not clear how someone physiologically is able to do this.” He suspects it may mean the divers are “mentally tolerating the symptoms longer.”

Olympic swimmers seem to be able to go great distances without breathing, but that is primarily due to aerobic conditioning, says Cowl. Those athletes are more efficient at getting oxygen into the tissue and extracting carbon dioxide. That allows them to breathe more effectively, and potentially, improve their breath holding.

Just being in the water may confer additional breath-holding ability. All mammals have what is known as a diving reflex. The involuntary reflex is most obvious—and pronounced—in aquatic mammals like whales and seals. But humans have this reflex, also. The purpose seems to be to conserve the oxygen that is naturally stored throughout the body, according to one study. 

When a mammal dives into the water, the heart rate slows, and the capillaries of extremities like arms and legs—or flippers—constrict. Blood and oxygen is redirected towards the internal organs. The reflex helps diving animals override the need to breathe, which means they can stay underwater longer.

It is not clear why the reflex developed, but further understanding could extend the boundaries of human performance.