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)

Diagnosing Alzheimer's disease can be a bit tricky. Traditional tests to confirm a person has Alzheimer's include an invasive spinal tap, a special PET scan which is quite expensive, and looking into a person's symptoms, then using cognitive exams to diagnose whether Alzheimer's could be the cause for their memory problems.

Now, a new Swedish study suggests that a certain form of blood testing may be more accurate than current methods. It's based on the idea that there are certain "biomarkers" which lead to the slow degeneration of a person's cognitive functioning.

In traditional tests, beta-amyloid was the primary biomarker being measured to confirm Alzheimer's. When this sticky protein builds up and forms plaques in the brain, it may block cell-to-cell signaling at synapses and even activate immune system cells that trigger inflammation and devour disabled cells.

Generally, it takes a period of about 20 years before the first signs and symptoms of Alzheimer's appear, however, that means several plaques have already accumulated and may have done considerable damage to the nerve cells in the brain.

Current medication to mitigate the progression of the disease is usually most effective when taken in the earlier stages of Alzheimer's, but it requires an early diagnosis as well, which, due to the incredible difficulty in identifying whether a person has already developed Alzheimer's, would also take time before a person is verified or cleared for the drug.

Since the diagnosis of Alzheimer's in patients is in a murky state, researchers have been trying to find new methods to detect Alzheimer's at the earliest possible moment. That's how this new Swedish study using blood tests came about.

The researchers looked at 1,200 patients who consulted a primary care doctor or a specialist for their memory problems, received an initial diagnosis, had blood tests taken, and then proceeded to get a spinal tap or PET scan for confirmation. In comparing the accuracy between the primary care doctors' initial diagnosis, the specialists' assessment, and the blood tests' results, the researchers from Lund University found that primary care doctors had a 61% accuracy rate, specialists had 73%, and the blood tests were 91% accurate.

Digging deeper into the gaps in accuracy between the three, one of the reasons why blood tests had higher accuracy in diagnosing for Alzheimer's was the fact that they measured another biomarker which was correlated with the development of Alzheimer's, called tau protein.

The benchmark measure being used in those blood tests is p-tau217, which, according to Dr. John Hsiao of the National Institute on Aging, and Maria Carrillo, the chief science officer of the Alzheimer's Association, was correlated with the amount of plaque buildup in a person's brain. If the blood test shows a high level of p-tau217, then there is a high probability that a person's memory problem is being caused by Alzheimer's. Otherwise, there may be other reasons.

At the moment, the companies offering p-tau217 tests include ALZpath Inc., Roche, Eli Lilly, and C2N Diagnostics. However, these tests can only be availed by the order of a doctor from the labs, since there are still no guidelines from the Alzheimer's Association regarding its use, neither is there FDA approval for the procedure as of yet.

Despite stressing the importance of getting an early diagnosis for Alzheimer's, these blood tests cannot yet be used for people who may be susceptible to Alzheimer's, due to their family's medical history, but have not yet shown any signs or symptoms of it. However, studies are being conducted on possible therapies for these people who are at high risk of getting Alzheimer's in the future.

For now, the only way to lower the chance of getting Alzheimer's or perhaps, preventing it completely, is to eat a healthy diet, exercise, and get enough rest and sleep. I would like to add to those pieces of advice engaging in activities that exercise the mind so as to keep it sharp and active, and staying away from stressful environments or anything that may cause stress.

(Image credit: Dmitriy Gutarev/Pixabay)

Ingenious, mesmerizing, and absolutely revolutionary. Those are only some of the words that we can use to describe the three Dennison sisters and their contribution to England's penny arcades.

When I was a child and my parents would bring me to the mall, there was one place I would always beg them to allow me to go, and that was the arcade. Making my way to that corner of the mall, flashing with neon lights and 8-bit sounds and music, a rush of excitement would fill my heart. I'd go up to the counter and exchange a bill for several tokens, and then I would wile away the time while my parents did their shopping.

A hundred years ago, such establishments also existed, like the Blackpool Tower in England. There, vacationers, holiday-makers, families, and other tourists would visit to see the attractions and find some entertainment in them.

Back then, Blackpool had a thriving tourism industry, taking notes from other places and attractions like Chicago's Ferris Wheel, Coney Island's rides, Berlin's trams, and the Eiffel Tower, a 518-foot replica of which had been constructed as a symbol for the image they wanted to portray of the city.

With all this flurry of excitement, innovation, and spectacle, John Dennison finally gained an avenue and opportunity to showcase his own arcade machines. Using his experience working at an engineering firm as well as drawing inspiration from his hobby of building automatic models, he displayed several of his coin-operated clockwork models of ships and agricultural machinery at Dr. Cocker's Aquarium, Aviary, and Menagerie on Blackpool's seafront.

Later on, when Dr. Cocker's was replaced by the Blackpool Tower, Dennison continued the partnership with the new management, retaining his contract to provide coin-operated working models to the new tourist attraction. The machines turned a profit for Dennison, given the thousands of tourists who visit the Tower each day, who, for a few pennies, were able to find some amusement in Dennison's moving machines.

In 1924, John Dennison passed away at 77, and not wanting the business to fall by the wayside, the three Dennison sisters — Florence (36), Alice (34), and Eveline (28) — continued what their father had started. Florence became the business manager while her younger sisters fiddled and tinkered with the machines along with the scenery, props, characters and their costumes, as well as the plot and setting of the dioramas.

Building on from their father's designs, they added more movement to the characters in the scenario, and provided more exciting plot twists and reveals, which infused their working models with a life of their own and increasing the drama and entertainment experienced by the audience who pinched their pennies into the machines.

The machines grew in popularity, owing to the appeal of their more morbid sceneries like the one pictured above titled "Murder in the Museum", a reference to and inspired by the American film which was released that same year they built the machine.

When they first took over the business, the sisters' working models raked in annual earnings of £1,586 (around $83,500 today). A decade later, they were making £2,624 (about $170,500 today). And then, in the midst of WWII, with Blackpool's tourist base now including soldiers on leave, London civil servants, and evacuated women and children, their machines earned them £6,831 (approximately $311,500 today).

In 1944, right after the war, the sisters decided to sell off their entire collection and live the rest of their lives from the proceeds. The machines themselves continued in popularity for the next two decades, while the women behind them were mostly forgotten. It even came to a point when the Blackpool Tower Company posted a request on the Blackpool Gazette regarding the origins of the machines, to which the sisters themselves replied.

Many of the Dennison sisters' machines are quite rare collectibles, as many of them were handcrafted and uniquely designed, with a lot of them now considered as "lost". However, if any do resurface, they become embroiled in fierce bidding wars between collectors.

Some of the machines that survived now live in museums. Murder in the Museum, one of the sisters' most popular machines, is currently housed at the Abbey House Museum in Leeds, and still retains its charm for evoking wonder, amusement, and a childlike joy from anyone who gets to see it in action.

(Image credit: Jenny Elliot; Leeds Museums and Galleries)

The biggest and the best entertainment extravaganzas were staged by Roman emperors who had the power and the wealth to do so. And the audiences were fairly bloodthirsty. The spectacles included chariot races, animal killing, executions, and gladiator fights. For around 200 years, women participated in those fights, and their bouts were often highlighted as the main event.

We don't have a lot of documentation on these female gladiators, and there's not even a Latin word for them, but we know they existed. Most were probably slaves, but there is some evidence that upper class women also participated, which was an even bigger draw. People disapproved of such behavior among higher-status women, but they also went to watch them fight each other. A woman who voluntarily became a gladiator was essentially throwing her reputation away, and that was worth watching, especially since they often fought topless and without a helmet to prove that they were indeed women. Read what little we know about the women gladiators of ancient Rome at Atlas Obscura.

Once upon a time, a bachelor's degree mostly meant that this person has a well-rounded education and can stick with a project for years at a time. That was a leg up in almost any job, no matter what subject the degree was in. Now it's too much of an investment to take any kind of risk. 

In the latest of Cracked's Honest Ads series, we learn the costs and benefits of a college degree. It can be quite a shock to the average 18-year-old to confront the costs and the debt they may have when they graduate. But once the dream is punctured, there are plenty of options for higher education. This scenario is a private college with a good reputation (except for Roger Horton's name on it). Students who are prepared for the college search ahead of time know that community college can get you quite a few credits for much less money, and a public university will cost less than a private school. For most careers, which school you go to matters little as long as it's accredited. But the real difference in a student's ability to pay back a student loan is whether they graduate, and whether the career they study for is something the world really needs.

Pictured above is William E. Dickey, the winner of the 1904 Olympics in the swimming event known as the plunge for distance. He doesn't look like a typical Olympic athlete because the plunge for distance was not a typical Olympic event. In fact, it was called the most boring sport of all time. The 1904 games were the only Olympics that the sport appeared in, and the only competitors were five Americans. But it was part of the competitive swimming scene in the US for decades.

The plunge for distance was a kind of competitive floating, to see how far an athlete could drift without any exertion after diving into a body of water. This particular act was made easier by extra body weight, as fat makes one more buoyant. It was taken seriously by those who competed, but for spectators, it was exceedingly dull, and the sport died out in the 1920s. Frank Parrington holds the world record in the plunge for distance at 86 feet 8 inches, a record that will stand forever. BBC Future talked to Parrington's grandson, Dave Parrington, head diving coach at the University of Tennessee, about the erstwhile sport of the plunge for distance.  -via Damn Interesting

(Image source: Missouri History Museum)

It's far too easy to pick up an infestation of bedbugs while staying in a hotel and then bringing the critters back home with you. That's why travel writer Lydia Mansel advocates for placing your luggage in the hotel room's bathtub as soon as you arrive.

Travel + Leisure magazine explains that bedbugs prefer to live in fabric surfaces, so the most straightforward solution is to reduce contact between your luggage and fabrics, such as the carpet.

You can also leave a note on your luggage to ask the housekeeping staff to leave your luggage in its otherwise puzzling location.

-via Nag on th Lake | Photo: Holidayextras

I once knew someone who had a screened-in party room at their house, and behind it was another screened-in room with a bed! It was a sleeping porch, used when it was too hot inside. This one caught breezes from three sides. Sleeping porches are one of many methods people used to keep cool before air conditioning became common. Pictured above is the freestanding sleeping porch President Taft had installed on the roof of the White House in 1910.

Evaporating water has been used for cooling for thousands of years, especially in dry areas. But it was used in the swampy city of Washington DC in 1881 after President Garfield was shot. His room in the White House was rigged with a device that blew air through wet fabric cooled with ice, and lowered the temperature by 20 degrees. It went through half a million pounds of ice over two months until Garfield died of his wounds.

Read about these and other clever methods that people used to keep cool in hot weather at Smithsonian.

You take all the standard tropes of a space adventure movie and put them together to make a parody. You shoot it in your apartment with a budget of zero and a cast of one playing all the parts. How good could it possibly be? In this one, it all comes down to the acting, and the zero-gravity effects, which were done only through acting. Oh yeah, there's one video effect, an illustration of product placement with a candy bar.

I saw a three-minute video on reddit and thought it was was quite good, and in fact was posted on the subreddit Best of the Internet. But I didn't post it here because I didn't know who made it. Then a friend pointed me in the right direction, and it turns out the full movie is nine minutes long and had a different ending. It was made by writer and actress Caroline Klidonas. Klidonas started posting vignettes on on TikTok during the pandemic lockdown that became full-blown productions. You can find quite a few of Klidones' full-length parodies at YouTube. -Thanks, Carol!   

In 1968, the Catholic Church established the Diocese of Orlando, which encompasses a large amount of central Florida. This area includes Cape Canaveral, from which the Apollo moon missions were launched in the late 1960s and early 1970s.

A 2019 article in L'Osservatore Romano, which is the Vatican's newspaper, republished at ETWN, reports that after the Apollo 11 landing in 1969, Bishop William Borders asserted episcopal authority over the moon.

The 1917 Code of Canon Law granted such authority over newly-discovered territories to the location of the launching expedition. Since Apollo 11 was launched within the boundaries of the Diocese of Orlando, the moon was the turf of Bishop Borders.

Bishop (later Archbishop) Borders once verbally asserted his lunar claim to Pope Paul VI, although the pontiff's response remains unknown.

-via Depths of Wikipedia | Photo: Archbishop William Borders and Pope Paul VI

If you were to tell a story about a late partygoer, you could mean someone who arrived long after the party started, or you might mean someone who died at a party. These very disparate uses of the word "late" can be confusing without the proper context. The reason that the word has two meanings goes back to the early use of "late" (pun intended). In the 15th century, the word was used to mean "recently." You can understand that by the phrase "of late." There are many examples that are now considered archaic, but we still use a form of it in phrases like "the latest comic from Randall Munroe." When referring to someone who died, the term "late" was originally only used for someone who passed away so recently that it might be news. But we strayed from that, and now say "the late Richard Harris," even though he died more than twenty years ago.

So the "behind schedule" definition has survived, and the "dead" meaning has been altered, but the in-between definition that meant "recently" has mostly fallen away. Read a rundown of how the word "late" has evolved over time at Mental Floss. Now, as far as the use of the phrase "the late, great..," that seems to have come about just because it rhymes and is therefore fun to say. -via Strange Company

(Image credit: Roman Eisele)

Have you always wanted to walk through the Slurm factory, enjoy a donut with The Simpsons or do an alien autopsy of Roger from American Dad? If so, you'll want to head to Hulu's Animayhem activation at this year's San Diego Comic Con.

There's a lot of fun to be had here, including a snack of green sprinkled donuts, refreshing Slurm, a Solar opposites stress test that gives you a relaxing squishy toy, and some incredible pins at the end.

If you are in the area this weekend, stop by for some fun. 

Kid Robot had been selling blank vinyl toys for years, making it easy to color your own designs amd create your own one-of-a-kind creation... But unless you start adding on to the sculpture, it will always be the same shape as everyone else's.

If you really want to let your inner artist shine, you'll want to check out Marmals. We spotted these at Comic Con and my son fell in love -and so did I. These adorable creations have magnetic parts so you can switch around the head, arm, and legs, and even change parts between different models to create entirely new creatures. You can even deck them out with adorable accessories like sneakers and beanies.

Need a little help getting your design started? They also sell sticker packs you can color in. Not into making your own art? Then check out the gorgeous galactic designs. Whether for an art toy, desk toy, or a kid's toy, these cute creations offer something for just about everyone.

With today's all-volunteer armed forces, we might forget how common military service once was. Throughout most of the 20th century, young men could expect to be called up for World War I, World War II, the Korean War, or the Vietnam War. In between wars, service was seen as a useful bridge to manhood, or to see the world, or to learn job skills. So it wasn't odd to see half the houses in your neighborhood occupied by a veteran and his family. The language they brought back from their service could be colorful, but even when it wasn't, these veterans retained a lot of jargon that fellow veterans would understand, and soon those terms were used by everyone. We know what these terms mean, but we don't know how they came about. Weird History looks at a whole bunch of everyday phrases and idioms we use that you might not know came from the military, as far back as the Revolutionary War.   

I can't vouch for how accurate these stories are. Commenters at YouTube are especially upset about "balls to the wall," which they contend predates aviation.

Charles Byrne was born in Ireland in 1761 and grew to be seven and a half feet tall. This made him two feet taller than everyone around him. As word of the "Irish Giant" got around, Byrne decided to go to London and make a living off his unusual stature, because there were plenty of people who would pay to see a giant. And there was a also surgeon who would pay to have a giant. John Hunter was that surgeon, as he was also an anatomist who had dissected many human bodies to study them. Hunter made no secret that he would like to take possession of Byrne's body when the time came, to further his scientific knowledge.

Byrne was in control of how he was exposed during his life, but the thought of being dissected and then displayed after death horrified him. Even though he was a young man, his health began to deteriorate. The giant let it be known that he didn't want John Hunter anywhere near his body if he were to die. Byrne died at age 22. He had already made plans for his friends to bury him at sea, with weights to keep his body submerged so that the anatomist couldn't get to him. We don't know for sure how his plan went awry, but Hunter indeed ended up with Byrne's body. He dissected it for four years and then Byrne's skeleton went on display for hundreds of years -until 2023. Read about the restless corpse of the Irish Giant at ABC. -via Strange Company

(Image credit: Maggie Jones)