The longest recorded time that a person held their breath underwater was 24 minutes and 37 seconds. That record is held by professional breath hold diver Budimir Šobat from Croatia, which was certified by the Guinness World Records on 27 March 2021. Šobat beat the previous record by 34 seconds.
In his attempt to beat the record, the 56-year-old freediver hyperventilated with pure oxygen beforehand, which the rules allowed for up to 30 minutes, and then he started the attempt. In order to achieve such a feat, Šobat said that during the whole time he submerged his face underwater, he only focused on trying to hear his heartbeat.
For mammals, having no gills to breathe freely underwater, there are several techniques to try and hold their breath for a long time. Training your body to be able to hold your breath longer would be the best way to increase the lung's capacity to hold more oxygen.
Freedivers use oxygen tables and carbon dioxide static apnea tables to develop the technique that allows them to hold their breath longer. They also do exercises like box breathing and diaphragmatic breathing to increase lung capacity. Finally, while training underwater, staying still helps in preserving the oxygen that they're holding.
Humans have to train hard if we want to develop the ability to hold our breath longer underwater. And it's an extremely useful skill to have, especially in cases of emergency, like when an accident occurs, and you find yourself trapped in a submerged vehicle or you get swept away by a rip current.
Pinnipeds, like seals and sea lions, have a much easier time holding their breath underwater, and that's because they're built differently from humans. Even though they're mammals, a new study found that the reason why these critters on flippers can last longer underwater lies in their hearts.
The longest time that any pinniped held their breath underwater was almost two hours, accomplished by a southern elephant seal. And the secret, according to the researchers was this structure in their hearts called an aortic bulb, which is essentially a very large artery that allows more oxygen to circulate throughout their body.
This aortic bulb, along with the animal's lower heart rate, allows it to conserve oxygen and stay submerged for longer periods of time. To verify this finding, scientists from the University of British Columbia compared data of heart size and dive durations from different seals — crabeater, leopard, harbor, and Weddell seals — then used ultrasound to measure the heart size of northern sea lions and northern fur seals.
The infographic above gives us a summary of their findings. As we can see in the lower left panel, the larger the aorta, the longer these seals were able to stay underwater which lends credence to the idea that their ability to hold their breath was thanks to this structure attached to their heart.
(Image credit: Mercedes Minck/Hakai Magazine)