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
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.
(Kenzo Tribouillard / AFP via Getty Images)
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
During the block, 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.
(Kenzo Tribouillard / AFP via Getty Images)
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
After Biles blocks off the vault, she is just a projectile.
(Matthias Hangst / Getty Images)
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
Simone Biles of the United States reacts after performing a vault during the 2023 gymnastics world championships in Antwerp, Belgium.
(Tim Clayton / Corbis via Getty Images)
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
Very little plastic being recycled in California as state efforts falter
California touts itself as a leader on the problem of plastic garbage, but recent developments suggest otherwise.
A new report issued by the state’s waste agency shows plastic yogurt containers, shampoo bottles and restaurant takeout trays are being recycled at rates only in the single digits.
-
Share via
Polypropylene, labeled as #5 on packaging, is used for yogurt containers, margarine tubs and microwavable trays. Only 2% of it is getting recycled. Colored shampoo and detergent bottles, made from polyethylene, or #1 plastic, are getting recycled at a rate of just 5%.
Other plastics, including ones promoted as highly recyclable, such as clear polyethylene bottles, which hold some medications, or hard water bottles, are being recycled at just 16%.
No plastic in the report exceeds a recycling rate of 23%, with the majority reported in just the single digits.
Adding to this disquieting assessment, CalRecycle also just pulled back regulations that were supposed to finalize a landmark single-use plastic law known as Senate Bill 54 — a law designed to make the majority of packaging waste in the state recyclable or compostable by working with the plastic and packaging industries.
The report and delay have sparked a wide variety of reactions by those who have closely watched the law as it was written and implemented.
The proposed regulations were regarded as friendly to industry. As a result, some are hopeful that CalRecycle’s decision to pull them back for tweaking means the agency will make the law stronger. Others say the two developments just show the state has never really been serious about plastic recycling.
“California’s SB 54 … will NEVER increase the recycling rates of these items … because cartons and plastic packaging are fundamentally not technically or economically recyclable,” said Jan Dell, the founder of Orange County-based Last Beach Cleanup, an anti-plastic organization.
Industry representatives are also expressing disappointment, saying the more delays and changes the state makes, the harder it is “for California businesses to comply with the law and implement the resulting changes,” said John Myers, a spokesman for the California Chamber of Commerce, which represents companies that will be affected.
Reports on abysmally low rates of recycling for milk cartons and polystyrene have been widely shared and known. But the newest numbers were still a grim confirmation that there are few options for dealing with these materials.
According to one state analysis, 2.9 million tons of single-use plastic and 171.4 billion single-use plastic components were sold, offered for sale or distributed in California in 2023.
Single-use plastics and plastic waste more broadly are considered a growing environmental and health problem. In recent decades, plastic waste has overwhelmed waterways and oceans, sickening marine life and threatening human health.
Last spring, the Newsom administration was accused of neutering the regulations that CalRecycle had initially proposed to implement the law. The changes excluded all packaging material related to produce, meat, dairy products, dog food, toothpaste, condoms, shampoo and cereal boxes, among other products. These are all products that might fall under the purview of the U.S. Food and Drug Administration and the U.S. Department of Agriculture.
It also opened the door to “alternative” recycling, such as chemical recycling, which environmentalists say is polluting, and was banned in the language of the law.
The waste agency then submitted those draft regulations to the Office of Administrative Law, whose lawyers and staff review proposed regulations to ensure they are “clear, necessary, legally valid, and available to the public” before finalizing them. They were set to release their determination on Friday; CalRecycle pulled the regulations back before the office issued its determination.
Neither the law office nor governor’s office responded to requests for comment.
Melanie Turner, CalRecycle’s spokeswoman, said the agency withdrew its proposed regulations “to make changes … to improve clarity and support successful implementation of the law,” and its revisions were focused on areas that dealt with “food and agricultural commodities.”
California State Sen. Ben Allen (D-Santa Monica), author of the original legislation, called the delay “entirely avoidable” in a statement, but said it would allow CalRecycle an “opportunity to ensure the regulations truly follow the law as it was signed.”
He urged the waste agency and Newsom’s administration not to “allow broad, sweeping exemptions that would undermine the program and increase costs for ratepayers.”
Critics of the watered-down regulations, such as Anja Brandon, the director of plastics policy for the Ocean Conservancy, said she wasn’t surprised by the withdrawal.
The proposed regulations “would have gone beyond CalRecycle’s authority by creating a sweeping categorical exclusion for food and agricultural packaging — effectively a loophole that would have allowed producers to continue putting vast amounts of plastic packaging into the marketplace, completely undermining SB 54’s goals and success,” she said in a text message.
Turner said CalRecycle will conduct a 15-day comment period — although when that begins has not yet been divulged.
Science
Cancer survival rates soar nationwide, but L.A. doctors warn cultural and educational barriers leave some behind
The American Cancer Society’s 2026 Cancer Statistics report, released Tuesday, marks a major milestone for U.S. cancer survival rates. For the first time, the annual report shows that 70% of Americans diagnosed with cancer can expect to live at least five years, compared with just 49% in the mid-1970s.
The new findings, based on data from national cancer records and death statistics from 2015 to 2021, also show promising progress in survival rates for people with the deadliest, most advanced and hardest-to-treat cancers when compared with rates from the mid-1990s. The five-year survival rate for myeloma, for example, nearly doubled (from 32% to 62%). The survival rate for liver cancer tripled (from 7% to 22%), for late-stage lung cancer nearly doubled (from 20% to 37%), and for both melanoma and rectal cancer more than doubled (from 16% to 35% and from 8% to 18%, respectively).
For all cancers, the five-year survival rate more than doubled since the mid-1990s, rising from 17% to 35%.
This also signals a 34% drop in cancer mortality since 1991, translating to an estimated 4.8 million fewer cancer deaths between 1991 and 2023. These significant public health advances result from years of public investment in research, early detection and prevention, and improved cancer treatment, according to the report.
“This stunning victory is largely the result of decades of cancer research that provided clinicians with the tools to treat the disease more effectively, turning many cancers from a death sentence into a chronic disease,” said Rebecca Siegel, senior scientific director at the American Cancer Society and lead author of the report.
As more people survive cancer, there is also a growing focus on the quality of life after treatment. Patients, families and caregivers face physical, financial and emotional challenges. Dr. William Dahut, the American Cancer Society’s chief scientific officer, said that ongoing innovation must go hand in hand with better support services and policies, so all survivors — not just the privileged — can have “not only more days, but better days.”
Indeed, the report also shows that not everyone has benefited equally from the advances of the last few decades. American Indian and Alaska Native people now have the highest cancer death rates in the country, with deaths from kidney, liver, stomach and cervical cancers about double that of white Americans.
Additionally, Black women are more likely to die from breast and uterine cancers than non-Black women — and Black men have the highest cancer rates of any American demographic. The report connects these disparities in survival to long-standing issues such as income inequity and the effects of past discrimination, such as redlining, affecting where people live — forcing historically marginalized populations to be disproportionately exposed to environmental carcinogens.
Dr. René Javier Sotelo, a urologic oncologist at Keck Medicine of USC, notes that the fight against cancer in Southern California, amid long-standing disparities facing vulnerable communities, is very much about overcoming educational, cultural and socioeconomic barriers.
While access to care and insurance options in Los Angeles are relatively robust, many disparities persist because community members often lack crucial information about risk factors, screening and early warning signs. “We need to insist on the importance of education and screening,” Sotelo said. He emphasized that making resources, helplines and culturally tailored materials readily available to everyone is crucial.
He cites penile cancer as a stark example: rates are higher among Latino men in L.A., not necessarily due to lack of access, but because of gaps in awareness and education around HPV vaccination and hygiene.
Despite these persisting inequities, the dramatic nationwide improvement in cancer survival is unquestionably good news, bringing renewed hope to many individuals and families. However, the report also gives a clear warning: Proposed federal cuts to cancer research and health insurance could stop or even undo these important gains.
“We can’t stop now,” warned Shane Jacobson, the American Cancer Society’s chief executive.
“We need to understand that we are not yet there,” Sotelo concurred. ”Cancer is still an issue.”
Science
Clashing with the state, L.A. City moves to adopt lenient wildfire ‘Zone Zero’ regulations
As the state continues multiyear marathon discussions on rules for what residents in wildfire hazard zones must do to make the first five feet from their houses — an area dubbed “Zone Zero” — ember-resistant, the Los Angeles City Council voted Tuesday to start creating its own version of the regulations that is more lenient than most proposals currently favored in Sacramento.
Critics of Zone Zero, who are worried about the financial burden and labor required to comply as well as the detrimental impacts to urban ecosystems, have been particularly vocal in Los Angeles. However, wildfire safety advocates worry the measures endorsed by L.A.’s City Council will do little to prevent homes from burning.
“My motion is to get advice from local experts, from the Fire Department, to actually put something in place that makes sense, that’s rooted in science,” said City Councilmember John Lee, who put forth the motion. “Sacramento, unfortunately, doesn’t consult with the largest city in the state — the largest area that deals with wildfires — and so, this is our way of sending a message.”
Tony Andersen — executive officer of the state’s Board of Forestry and Fire Protection, which is in charge of creating the regulations — has repeatedly stressed the board’s commitment to incorporating L.A.’s feedback. Over the last year, the board hosted a contentious public meeting in Pasadena, walking tours with L.A. residents and numerous virtual workshops and hearings.
-
Share via
Some L.A. residents are championing a proposed fire-safety rule, referred to as “Zone Zero,” requiring the clearance of flammable material within the first five feet of homes. Others are skeptical of its value.
With the state long past its original Jan. 1, 2023, deadline to complete the regulations, several cities around the state have taken the matter into their own hands and adopted regulations ahead of the state, including Berkeley and San Diego.
“With the lack of guidance from the State Board of Forestry and Fire Protection, the City is left in a precarious position as it strives to protect residents, property, and the landscape that creates the City of Los Angeles,” the L.A. City Council motion states.
However, unlike San Diego and Berkeley, whose regulations more or less match the strictest options the state Board of Forestry is considering, Los Angeles is pushing for a more lenient approach.
The statewide regulations, once adopted, are expected to override any local versions that are significantly more lenient.
The Zone Zero regulations apply only to rural areas where the California Department of Forestry and Fire Protection responds to fires and urban areas that Cal Fire has determined have “very high” fire hazard. In L.A., that includes significant portions of Silver Lake, Echo Park, Brentwood and Pacific Palisades.
Fire experts and L.A. residents are generally fine with many of the measures within the state’s Zone Zero draft regulations, such as the requirement that there be no wooden or combustible fences or outbuildings within the first five feet of a home. Then there are some measures already required under previous wildfire regulations — such as removing dead vegetation like twigs and leaves, from the ground, roof and gutters — that are not under debate.
However, other new measures introduced by the state have generated controversy, especially in Los Angeles. The disputes have mainly centered around what to do about trees and other living vegetation, like shrubs and grass.
The state is considering two options for trees: One would require residents to trim branches within five feet of a house’s walls and roof; the other does not. Both require keeping trees well-maintained and at least 10 feet from chimneys.
On vegetation, the state is considering options for Zone Zero ranging from banning virtually all vegetation beyond small potted plants to just maintaining the regulations already on the books, which allow nearly all healthy vegetation.
Lee’s motion instructs the Los Angeles Fire Department to create regulations in line with the most lenient options that allow healthy vegetation and do not require the removal of tree limbs within five feet of a house. It is unclear whether LAFD will complete the process before the Board of Forestry considers finalized statewide regulations, which it expects to do midyear.
The motion follows a pointed report from LAFD and the city’s Community Forest Advisory Committee that argued the Board of Forestry’s draft regulations stepped beyond the intentions of the 2020 law creating Zone Zero, would undermine the city’s biodiversity goals and could result in the loss of up to 18% of the urban tree canopy in some neighborhoods.
The board has not decided which approach it will adopt statewide, but fire safety advocates worry that the lenient options championed by L.A. do little to protect vulnerable homes from wildfire.
Recent studies into fire mechanics have generally found that the intense heat from wildfire can quickly dry out these plants, making them susceptible to ignition from embers, flames and radiant heat. And anything next to a house that can burn risks taking the house with it.
Another recent study that looked at five major wildfires in California from the last decade, not including the 2025 Eaton and Palisades fires, found that 20% of homes with significant vegetation in Zone Zero survived, compared to 37% of homes that had cleared the vegetation.
-
Montana4 days agoService door of Crans-Montana bar where 40 died in fire was locked from inside, owner says
-
Technology1 week agoPower bank feature creep is out of control
-
Delaware6 days agoMERR responds to dead humpback whale washed up near Bethany Beach
-
Dallas, TX6 days agoAnti-ICE protest outside Dallas City Hall follows deadly shooting in Minneapolis
-
Dallas, TX1 week agoDefensive coordinator candidates who could improve Cowboys’ brutal secondary in 2026
-
Education1 week agoVideo: This Organizer Reclaims Counter Space
-
Virginia4 days agoVirginia Tech gains commitment from ACC transfer QB
-
Iowa1 week agoPat McAfee praises Audi Crooks, plays hype song for Iowa State star