Science
Science of Simone: The forces behind her iconic Yurchenko double pike
The most decorated gymnast ever sprints down the vault runway. She tumbles gracefully onto the springboard, flings herself backward onto the vault table and pops off the surface. Soaring through the air, she folds her body in half and grabs the back of her legs for two head-over-heels flips.
The crowd erupts when Simone Biles stomps her feet into the mat.
Another successful Yurchenko double pike.
“It just makes your mouth drop open every time,” said UCLA gymnastics coach Janelle McDonald, who sat in the front row next to the vault landing area at the U.S. Olympic trials, where Biles competed her signature vault.
Of the five skills in the International Gymnastics Federation (FIG) code of points named after Biles, her most recent vault — the Yurchenko double pike — has become the most iconic.
It’s the first major leap in vault innovation for women’s artistic gymnastics in two decades. When leveling up the sky-high event used to mean extra twists, Biles flipped the game upside down. She was the first woman to attempt her double-flipping skill in competition and completed it in international competition for the first time at the 2023 World Championships, earning its name as the Biles II.
“Simone made impossible an opinion with that vault,” NBC analyst John Roethlisberger said on the telecast during the U.S. Olympic trials.
In a sport that blends power and grace, Biles’ Yurchenko double pike is at the center of its own Venn diagram: athletic feat, scientific marvel and artistic genius all in six seconds.
The entry
The height, the rotation and the landing earn the most gasps from the fans who follow Biles’ every move on the competition floor. But for her peers who continue to marvel at the 27-year-old’s revolutionary talent, the most impressive part of the vault happens before Biles even contacts the table.
“Your Yurchenko entry has to be so technically perfect and so consistent,” said 2016 Olympic gold medalist Kyla Ross. “You have no doubt coming off the table that you’re going to hit the double pike.”
The Yurchenko entry — a roundoff onto the springboard and a back handspring onto the vault table — is named after former Russian gymnast Natalia Yurchenko, who debuted her eponymous skill in 1982. Since the FIG replaced the vault horse — which resembled a pommel horse without handles and was about 5 feet long and 1 foot wide at the top — for a tongue-shaped vault table in 2001, the Yurchenko vault has become more common for elite female gymnasts. Athletes can still harness the power generated from the unique entry while having a larger, safer surface area for their hands.
2024 Paris Summer Olympic Games
Biles begins with a sprint down the runway and reaches her hands toward the ground while cartwheeling her legs over her head. The roundoff turns her momentum forward to backward. Slamming her feet down on the springboard, Biles compresses the springs that then uncoil and transfer energy back into her body as she reaches up and backward for the vault table.
The key to vault liftoff is how Biles contacts the equipment to transfer her momentum.
“Pre-springboard, all of their motion is forwards,” said Emily Kuhn, a physics PhD student at Yale who was a level 10 gymnast. “After the springboard, some of their motion is upwards. And so [the board is] really helpful for converting the rotational energy from that roundoff into an upwards velocity that is used to get the height on the vault.”
In an instant, Biles arches backward toward the vault table. Her body whips back in a lightning-fast handspring that leaves even the best athletes in the world in the dust.
“She gets that power because of how quick-twitched her roundoff-back handspring is, technically speaking,” said 2008 Olympic silver medalist Samantha Peszek. “No one is as quick-twitch as Simone.”
The block
Aly Raisman had a front-row seat to the world’s best vaulters. The two-time Olympian watched 2012 Olympic teammate McKayla Maroney nail a nearly perfect two-and-a-half twisting Yurchenko in the team final. Raisman was also the team captain in 2016 when Biles won Olympic gold on vault. Both standouts shared a key ability that helped them soar above the competition.
“When you look at her elbows on the table, they’re always very straight,” Raisman said. “Their body was so tight when their arms hit the table that it just helps them get so much air.”
The moment Biles’ hands strike the table, she extends through her shoulders in a motion that’s barely detectable in real time. The micro-movement lasts a tenth of a second as Biles applies force to the vault that is then returned in equal and opposite measure. Keeping every muscle contracted during the split second on the table is vital to transferring energy efficiently for maximum height.
“The force gets dispersed in bad form,” said Gina Pongetti, a physical therapist with more than 20 years of experience working with college, national team and elite gymnasts. “[The muscles] are all tight at one time so that nothing gives, nothing buckles. Because of that, all of that force, or as much as possible, goes into the vault [and] goes back to her to transfer to height and rotation.”
NBC estimated that Biles’ feet reach about 12 feet in the air at the peak of her vault when she is upside down.
Former UCLA gymnast Nia Dennis knows the feeling. The three-time U.S. national team member trained a Yurchenko double tuck — with her knees bent and legs pulled toward her chest — into the foam pit during her elite career, eventually stacking up soft mats to be equal to competition height. While she is best known for her viral, energetic floor routines, Dennis loved vault the most. She still recalls the intoxicating feeling of hitting the perfect block that fired her into the air.
“I just felt like a cannon,” Dennis said.
The flips
Searching for ways to upgrade her vault difficulty, Dennis wanted to buck the trend of adding additional twists to her Yurchenko. She was always more of a flipper than a twister, and Dennis sometimes landed on her neck from over-rotating her warm-up drills. One day, her coach encouraged her to pull all the way around onto her feet for an additional flip.
“It was just straight power,” Dennis said. “All I had to do was run and close my eyes, for real. Just block really hard, close my eyes really hard and pull really hard.”
For Dennis, the daring skill was fun. Her former UCLA teammate Ross did not share the sentiment.
“I used to like, cry because I was so scared of it,” laughed Ross, who practiced Yurchenko double tucks into the foam pit alongside her longtime club teammate Maroney.
The second flip is what makes the vault so frightening for athletes. Gymnasts can adjust a twisting vault midair by reducing the number of revolutions by halves if they feel something gone awry. There is no safe Plan B between one and two flips.
After Biles blocks off the vault, she is just a projectile, Kuhn emphasized. At that point, there is nothing she can do to change how high she is or her path through the air.
That’s when her proprioception takes over. Biles’ air awareness is “unbelievable,” Pongetti said. The physical therapist, who specializes in treatment, diagnoses and biomechanics in gymnastics, has watched Biles train for years.
While she cannot change her flight path, Biles is an expert in making split-second decisions to rearrange her body midair to change how she will move. If she is too low, she can pull her body into a tighter shape to flip faster. If she is too high, she knows a more open shape can slow down her flip and help avoid over-rotation.
Only that caliber of spatial awareness can make the death-defying skill “safer,” Pongetti said. She would never say it’s “safe.”
“That sets apart the level 10 [gymnast] from the elite,” Pongetti said, “from the Olympian from Simone.”
The landing
With five skills named for her in the code of points, Biles is at the forefront of the sport’s progression. Peszek remembers when the double-twisting, double back tucks she and 2008 Olympic teammate Shawn Johnson competed were arguably the hardest tumbling passes in the world. Now Biles casually does that skill in combination with a full-twisting front layout.
“It’s really special to see the generations pass the torch and just how they’ve been able to take this sport by storm by creating all these new elements and really pushing the boundaries,” Peszek said. “Seeing her do it so effortlessly, it’s really a work of art to see.”
The Biles II was awarded the highest-difficulty score of any vault by the FIG at 6.4. Astronomical-difficulty scores, which are combined on each event with an execution score out of 10, allow Biles to win competitions by whole numbers as most of her peers fight for half-tenths.
On vault, most of the top medal contenders have difficulty values of 5.4 for the two-and-a-half twisting Yurchenko known as an Amanar or 5.6 for a Cheng, which begins with a roundoff onto the springboard, a half turn onto the vault table and a one-and-a-half twist off.
But Rebeca Andrade could challenge Biles for the crown. The Brazilian Olympic confederation published a YouTube video that featured the Olympic and world vault champion training a triple-twisting Yurchenko. If she lands it in international competition, it will bear her name.
Biles considered the skill as the next Yurchenko progression from an Amanar but has said going for the double flip was safer for her to land. The landing on a twisting flip presents additional challenges, Kuhn said, as gymnasts must absorb rotational forces to stop the twist while also controlling the landing vertically.
A 2013 study estimated that gymnasts absorb 11 times their body weight on landings during competition. The force increases to 18 times body weight if a landing is uneven, a common consequence of twisting elements. What Biles feels when her 4-foot-8 frame is falling from more than two and a half times her height to land the Yurchenko double pike might be even greater, Pongetti said.
“Her quads and her glutes and her hamstrings [and her calves], which otherwise would work to allow her to jump high, work in reverse to slow her down,” Pongetti said. “They are her brakes. … She is so good at not being stiff-legged when she lands.”
Fans seem to hold their breath as Biles floats and flips through the air. At the moment her feet punch into the mat, the crowd exhales with a roar of applause.
Thousands in Paris’ Bercy Arena will see the vault’s official Olympic debut. Millions more will watch internationally.
They’ll see Biles push the boundaries of sport and science in a gravity-defying six-second burst.
Science
How to protect yourself from the smoke caused by L.A. wildfires
You don’t have to live close to a wildfire to be affected by its smoke. With severe winds fanning the fires in and around Pacific Palisades, the Pasadena foothills and Simi Valley, huge swaths of the Southland are contending with dangerous air quality.
Wildfire smoke can irritate your eyes, nose, throat and lungs. The soot may contain all kinds of dangerous pollutants, including some that may cause cancer. The tiniest particles in smoke can travel deep into your lungs or even enter your bloodstream.
Conditions like these aren’t good for anyone, but they’re particularly bad for people in vulnerable groups, including children, those with asthma or other respiratory conditions, people with heart disease and those who are pregnant.
Here’s what you should know to keep yourself safe.
Stay indoors
Minimize your exposure to unhealthy air by staying inside and keeping your doors and windows shut.
If you have a central heating and air conditioning system, you can keep your indoor air clean by turning it on and keeping it running. Make sure the fresh-air intake is closed so that you’re not drawing in outdoor air.
Keep your pets inside
They shouldn’t breathe the unhealthy air either.
Check your air filters
Clean filters work better than dirty ones, and high-efficiency filters work better than regular ones. The California Air Resources Board and the South Coast Air Quality Management District recommend filters with a MERV rating of 13 or higher.
You might consider using portable high-efficiency air cleaner in a room where you spend the most time. The U.S. Environmental Protection Agency has information about them here, and CARB has a list of certified cleaning devices here.
Don’t pollute your indoor air
That means no burning candles or incense. If your power is out and you need to see in the dark, you’re much better off with a flashlight or headlamp.
If you’re cold, bundle up. This is not the time to start a cozy fire in the fireplace. Don’t use a gas stove or wood-fired appliances, since these will make your indoor air quality worse, not better, the AQMD says.
The CDC also advises against vacuuming, since it can stir up dust and release fine particles into the air.
Take care when cleaning up
You don’t want your skin to come into contact with wildfire ash. That means you should wear long sleeves, pants, gloves, socks and shoes. The AQMD even wants you to wear goggles.
If you’re sweeping up ash outdoors, get a hose and mist it with water first. That will keep it from flying up in the air as you move it around. Once the ash is wet, sweep it up gently with a broom or mop. Bag it up in a plastic bag and throw it away.
It’s a good idea to wash your vehicles and outdoor toys if they’re covered in ash. Try not to send ashy water into storm drains. Direct the dirty water into ground areas instead, the AQMD advises.
Those with lung or heart problems should avoid clean-up activities.
Discard spoiled food…
If you lost power for a significant length of time, the food in your refrigerator or freezer may be spoiled.
Food kept in a fridge should stay safe for up to four hours if you’ve kept the door closed. If you’ve been without power for longer than that, you’ll need to toss all perishable items, including meat, poultry, fish, eggs, milk and cut fruits and vegetables. Anything with “an unusual smell, color, or texture” should be thrown out as well, according to the U.S. Centers for Disease and Control Prevention.
Refrigerated medicines should be OK unless the power was out for more than a day. Check the label to make sure.
…even if it was in the freezer
Your freezer may be in better shape, especially if it’s well-stocked. Items in a full freezer may be safe for up to 48 hours if it’s been kept shut, and a half-full freezer may be OK for up to 24 hours. (The frozen items help keep each other cold, so the more the better.)
If items have remained below 40 degrees Fahrenheit (4 degrees Celsius) or you can still see ice crystals in them, they may be OK to use or refreeze, according to the federal government’s food safety website.
Ice cream and frozen yogurt should be thrown out if the power goes out for any amount of time. Meat, poultry, seafood, eggs, milk and most other dairy products need to go if they were exposed to temperatures above 40 degrees F for two hours or longer. The same goes for frozen meals, casseroles, soups, stews and cakes, pies and pastries with custard or cheese fillings.
Fruit and fruit juices that have started to thaw can be refrozen unless they’ve started to get moldy, slimy or smell like yeast. Vegetables and vegetable juices should be discarded if they’ve been above 40 degrees F for six hours or more, even if they look and smell fine.
Breakfast items like waffles and bagels can be refrozen, as can breads, rolls, muffins and other baked goods without custard fillings.
Consider alternative shelter
If you’ve done everything you can but your eyes are still watering, you can’t stop coughing, or you just don’t feel well, seek alternative shelter where the air quality is better.
Hold off on vigorous exercise
Doing anything that would cause you to breathe in more deeply is a bad idea right now.
Mask up outdoors
If you need to be outside for an extended time, be sure to wear a high-quality mask. A surgical mask or cloth mask won’t cut it — health authorities agree that you should reach for an N95 or P-100 respirator with a tight seal.
Are young children at greater risk of wildfire smoke?
Very young children are especially vulnerable to the effects of wildfire smoke because their lungs are still rapidly developing. And because they breathe much faster than adults, they are taking in more toxic particulate matter relative to their tiny bodies, which can trigger inflammation, coughing and wheezing.
Any kind of air pollution can be dangerous to young children, but wildfire smoke is about 10 times as toxic for children compared to air pollution from burning fossil fuels, said Dr. Lisa Patel, clinical associate professor of pediatrics at Stanford Children’s Health. Young children with preexisting respiratory problems like asthma are at even greater risk.
Patel advises parents to keep their young children indoors as much as possible, create a safe room in their home with an air purifier, and try to avoid using gas stoves to avoid polluting the indoor air.
Children over the age of 2 should also wear a well-fitting KN95 mask if they will be outdoors for a long period of time. Infants and toddlers younger than that don’t need to mask up because it can be a suffocation risk, Patel said.
What are the risks for pregnant people?
Pregnant people should also take extra precautions around wildfire smoke, which can cross the placenta and affect a developing fetus. Studies have found that exposure to wildfire smoke during pregnancy can increase the risk of premature birth and low birth weight. Researchers have also linked the toxic chemicals in smoke with maternal health complications including hypertension and preeclampsia.
What about other high-risk populations?
Certain chronic diseases including asthma, chronic obstructive pulmonary disease or other respiratory conditions can also make you particularly vulnerable to wildfire smoke. People with heart disease, diabetes and chronic kidney disease should take extra care to breathe clean air, the CDC says. The tiny particles in wildfire smoke can aggravate existing health problems, and may make heart attacks or strokes more likely, CARB warns.
Get ready for the next emergency
Living in Southern California means another wildfire is coming sooner or later. To prepare for the bad air, you can:
- Stock up on disposable respirators, like N95 or P-100s.
- Have clean filters ready for your A/C system and change them out when things get smoky.
- Know how to check the air quality where you live and work. The AQMD has an interactive map that’s updated hourly. Just type in an address and it will zoom in on the location. You can also sign up to get air quality alerts by email or on your smartphone.
- Know where your fire extinguisher is and keep it handy.
- If you have a heart or lung condition, keep at least five days’ worth of medication on hand.
Times staff writer Karen Garcia contributed to this report.
Science
Punk and Emo Fossils Are a Hot Topic in Paleontology
Mark Sutton, an Imperial College London paleontologist, is not a punk.
“I’m more of a folk and country person,” he said.
But when Dr. Sutton pieced together 3-D renderings of a tiny fossil mollusk, he was struck by the spikes that covered its wormlike body. “This is like a classic punk hairstyle, the way it’s sticking up,” he thought. He called the fossil “Punk.” Then he found a similar fossil with downward-tipped spines reminiscent of long, side-swept “emo” bangs. He nicknamed that specimen after the emotional alt-rock genre.
On Wednesday, Dr. Sutton and his colleagues published a paper in the journal Nature formally naming the creatures as the species Punk ferox and Emo vorticaudum. True to their names, these worm-mollusks are behind something of an upset (if not quite “anarchy in the U.K.”) over scientists’ understanding of the origins of one of the biggest groups of animals on Earth.
In terms of sheer number of species, mollusks are second only to arthropods (the group that contains insects, spiders and crustaceans). The better-known half of the mollusk family tree, conchiferans, contains animals like snails, clams and octopuses. “The other half is this weird and wacky group of spiny things,” Dr. Sutton said. Some animals in this branch, the aculiferans, resemble armored marine slugs, while others are “obscure, weird molluscan worms,” he said.
Punk and Emo, the forerunners of today’s worm-mollusks, lived on the dark seafloor amid gardens of sponges, nearly 200 million years before the first dinosaurs emerged on land. Today, their ancient seafloor is a fossil site at the border between England and Wales.
The site is littered with rounded rocky nodules that “look a bit like potatoes,” Dr. Sutton said. “And then you crack them open, and some of them have got these fossils inside. But the thing is, they don’t really look like much at first.”
While the nodules can preserve an entire animal’s body in 3-D, the cross-section that becomes visible when a nodule is cracked open can be difficult to interpret “because you’re not seeing the full anatomy,” Dr. Sutton said.
Paleontologists can use CT scans to see parts of fossils still hidden in rock, essentially taking thousands of X-rays of the fossil and then stitching those X-ray slices together into one digital 3-D image. But in these nodules, the fossilized creatures and the rock surrounding them are too similar in density to be easily differentiated by X-rays. Instead, Dr. Sutton essentially recreated this process of slicing and imaging by hand.
“We grind away a slice at a time, take a photo, repeat at 20-micron intervals or so, and basically destroy but digitize the fossil as we go,” Dr. Sutton said. At the end of the process, the original fossil nodule is “a sad-looking pile of dust,” but the thousands of images, when painstakingly digitally combined, provide a remarkable picture of the fossil animal.
Punk and Emo’s Hot Topic-worthy spikes set them apart from other fossils from the aculiferan branch of the mollusk family. “We don’t know much about aculiferans, and it’s unusual to find out we’ve suddenly got two,” Dr. Sutton said.
Stewart Edie, the curator of fossil bivalves at the Smithsonian National Museum of Natural History, said that Punk and Emo’s bizarre appearances shook up a long-held understanding of how mollusks evolved. Traditionally, scientists thought that the group of mollusks containing snails, clams and cephalopods “saw all of the evolutionary action,” said Dr. Edie, who was not involved with the new discovery. “And the other major group, the aculiferans, were considerably less adventurous.” But Punk and Emo “buck that trend,” he said.
The new alt-rock aculiferans reveal the hidden diversity of their group in the distant past and raise questions about why their descendants make up such a small part of the mollusk class today. “This is really giving us an almost unprecedented window into the sorts of things that were actually around when mollusks were getting going,” Dr. Sutton said. “It’s just this little weird, unexpected, really clear view of what was going on in the early history of one of the most important groups of animals.”
Science
FDA sets limits for lead in many baby foods as California disclosure law takes effect
The U.S. Food and Drug Administration this week set maximum levels for lead in baby foods such as jarred fruits and vegetables, yogurts and dry cereal, part of an effort to cut young kids’ exposure to the toxic metal that causes developmental and neurological problems.
The agency issued final guidance that it estimated could reduce lead exposure from processed baby foods by about 20% to 30%. The limits are voluntary, not mandatory, for food manufacturers, but they allow the FDA to take enforcement action if foods exceed the levels.
It’s part of the FDA’s ongoing effort to “reduce dietary exposure to contaminants, including lead, in foods to as low as possible over time, while maintaining access to nutritious foods,” the agency said in a statement.
Consumer advocates, who have long sought limits on lead in children’s foods, welcomed the guidance first proposed two years ago, but said it didn’t go far enough.
“FDA’s actions today are a step forward and will help protect children,” said Thomas Galligan, a scientist with the Center for Science in the Public Interest. “However, the agency took too long to act and ignored important public input that could have strengthened these standards.”
The new limits on lead for children younger than 2 don’t cover grain-based snacks such as puffs and teething biscuits, which some research has shown contain higher levels of lead. And they don’t limit other metals such as cadmium that have been detected in baby foods.
The FDA’s announcement comes just one week after a new California law took effect that requires baby food makers selling products in California to provide a QR code on their packaging to take consumers to monthly test results for the presence in their product of four heavy metals: lead, mercury, arsenic and cadmium.
The change, required under a law passed by the California Legislature in 2023, will affect consumers nationwide. Because companies are unlikely to create separate packaging for the California market, QR codes are likely to appear on products sold across the country, and consumers everywhere will be able to view the heavy metal concentrations.
Although companies are required to start printing new packaging and publishing test results of products manufactured beginning in January, it may take time for the products to hit grocery shelves.
The law was inspired by a 2021 congressional investigation that found dangerously high levels of heavy metals in packaged foods marketed for babies and toddlers. Baby foods and their ingredients had up to 91 times the arsenic level, up to 177 times the lead level, up to 69 times the cadmium level, and up to five times the mercury level that the U.S. allows to be present in bottled or drinking water, the investigation found.
There’s no safe level of lead exposure for children, according to the U.S. Centers for Disease Control and Prevention. The metal causes “well-documented health effects,” including brain and nervous system damage and slowed growth and development. However, lead occurs naturally in some foods and comes from pollutants in air, water and soil, which can make it impossible to eliminate entirely.
The FDA guidance sets a lead limit of 10 parts per billion for fruits, most vegetables, grain and meat mixtures, yogurts, custards and puddings and single-ingredient meats. It sets a limit of 20 parts per billion for single-ingredient root vegetables and for dry infant cereals. The guidance covers packaged processed foods sold in jars, pouches, tubs or boxes.
Jaclyn Bowen, executive director of the Clean Label Project, an organization that certifies baby foods as having low levels of toxic substances, said consumers can use the new FDA guidance in tandem with the new California law: The FDA, she said, has provided parents a “hard and fast number” to consider a benchmark when looking at the new monthly test results.
But Brian Ronholm, director of food policy for Consumer Reports, called the FDA limits “virtually meaningless because they’re based more on industry feasibility and not on what would best protect public health.” A product with a lead level of 10 parts per billion is “still too high for baby food. What we’ve heard from a lot of these manufacturers is they are testing well below that number.”
The new FDA guidance comes more than a year after lead-tainted pouches of apple cinnamon puree sickened more than 560 children in the U.S. between October 2023 and April 2024, according to the CDC.
The levels of lead detected in those products were more than 2,000 times higher than the FDA’s maximum. Officials stressed that the agency doesn’t need guidance to take action on foods that violate the law.
Aleccia writes for the Associated Press. Gold reports for The Times’ early childhood education initiative, focusing on the learning and development of California children from birth to age 5. For more information about the initiative and its philanthropic funders, go to latimes.com/earlyed.
-
Business1 week ago
These are the top 7 issues facing the struggling restaurant industry in 2025
-
Culture1 week ago
The 25 worst losses in college football history, including Baylor’s 2024 entry at Colorado
-
Sports1 week ago
The top out-of-contract players available as free transfers: Kimmich, De Bruyne, Van Dijk…
-
Politics7 days ago
New Orleans attacker had 'remote detonator' for explosives in French Quarter, Biden says
-
Politics6 days ago
Carter's judicial picks reshaped the federal bench across the country
-
Politics5 days ago
Who Are the Recipients of the Presidential Medal of Freedom?
-
Health4 days ago
Ozempic ‘microdosing’ is the new weight-loss trend: Should you try it?
-
World1 week ago
Ivory Coast says French troops to leave country after decades