Science
How do Olympic skateboarders catch serious airtime? Physicists crunched the numbers
Skateboarders call it “pumping,” and it’s a skill that both Olympic medalists and aspiring thrashers use to build launch speed from what seems like thin air.
But what separates the steeziest pro from the sketchiest beginner is the years’ worth of practice it takes to develop the know-how to execute the cleanest pump — or at least that was the case until now.
In a paper published Monday in the journal Physical Review Research, scientists have revealed the secret of achieving serious airtime.
A skateboarder rides the bowls at Etnies skatepark in Lake Forest. (Allen J. Schaben / Los Angeles Times)
With a bit of coding, researchers were able to describe the optimal technique for pumping — a tactic where skateboarders crouch down low momentarily and then push their body upright on inclines. To get the highest jump, they need to do it once as they descend into the bowl, and then again as they shoot back up toward the sky.
The trick is knowing when and where to execute the maneuver.
“Pumping is the foundation of skateboarding in skate parks,” said professional skater Haden McKenna, during a morning session at the Venice Beach Skatepark. “You build off of that and learn tricks. Then the pumping just becomes something in the back of your brain.”
However, the likeliest users of the researchers’ perfect pump equation are non-humans.
After skateboarding’s Olympic debut at the Tokyo Games, a research arm of the Japanese government reached out to Shigeru Shinomoto, a scientist at the Advanced Telecommunications Research Institute International in Japan. The organization had wondered if it was possible to build a skateboarding robot that could compete in the X Games.
The robot is still a ways off — right now it’s more like a toy that rides back and forth on a mini half-pipe — but the researchers discovered that the mechanics for good skateboarding technique can be surprisingly simple (well, at least compared to the complex fluid dynamics and neuroscience that they’re normally working on).
Kokona Hiraki of Japan crouches on her board before popping upright to pump at the Tokyo Olympics.
(Associated Press)
“It’s just this cute little project which became much bigger than we expected,” said Florian Kogelbauer, an author on the paper and a mechanical engineering professor at the public university ETH Zürich. “People like it — it’s a fun topic. It’s easy to explain, but some serious math and computational work went into it.”
To test their calculations, study authors recruited an expert skater with over a decade of experience, and a novice with just two years under their belt. They told the skaters to catch as much air as possible on a half-pipe erected in a research lab.
The result: The pro much more closely matched their calculated optimal motion than the amateur. (Ideally the skater would pop up instantaneously, but the researchers conceded that humans lack the unlimited muscle strength to do this — plus it would send the skater flying off their board.)
“The experiment seems to agree well,” said Frank Feng, a mechanical engineering professor at the University of Missouri who was not involved with the paper, but studied similar motions in half-pipe snowboarding.
Feng said the simple physics model gets researchers most of the way there, then the computer optimization is able to account for complexities that the physics equations can’t handle.
While the study was mostly just for fun, it snowballed into a fairly big project, and ended up getting published in one of the world’s premier physics journals. Part of the reason is that it may have some serious implications for how to get robots to move effectively without face-planting all the time.
It could help human skateboarders, too. Feng said the results could be used as a straightforward guide to help skateboarders train.
However, some question whether skaters would be able to use the information in the moment.
“This graph, showing the mass going up, is very helpful for somebody that can understand that,” said pro skater McKenna, who was not involved in the research. “But when you’re teaching kids and you’re trying to teach somebody that’s focused in the moment of skateboarding, they’re not going to be able to bring math into the equation.”
Also, out in the complex terrain of the park, the technique gets a bit more nuanced than a simple model the physicists developed. You need to flow as “one with the wall,” said McKenna. “Like what Bruce Lee says, ‘Be like water.’”
Skateboarder Greyson Godfrey, 20, of Rancho Santa Margarita drops into the bowl at Etnies Skate Park Lake Forest.
(Allen J. Schaben / Los Angeles Times)
While the researchers’ optimal solution may not always be the best suited for real-world conditions, it does help to illustrate the physics behind the technique.
Studio Gutierrez, who teaches skateboarding as a sports instructor to middle schoolers in the Los Angeles Unified School District, finds understanding the science helpful for new skaters. “I explain it to them in physics motions,” he said. “The more motion, the faster you go, the higher you get.”
The physics works similarly to how ice skaters increase the speed of their spinning in the Winter Olympics, said Kogelbauer. They start out spinning slow with their limbs extended outward. Then, they tuck their arms and legs in, causing them to spin faster.
Skateboarders also gain speed by using this technique on curved surfaces.
When a skateboarder hits the circular section of the half-pipe, they start crouched down, positioning their center of mass further from the center of rotation above their head. As they climb the curved ramp, they pop up and bring their center of mass closer to the center of rotation, and they speed up.
While the pumping paper is one of the first to capture the physics of pumping, its authors aren’t the only ones studying the motion of skateboarding.
Google has also taken a stab at a more complex understanding with its Project Skate. It’s using AI to identify different tricks and motions — but AI requires a lot of computing power that many researchers who aren’t Google don’t have access to.
“They have [essentially] unlimited resources. If they want to, they can take a new server farm and then run trajectories as much as they want.” said Kogelbauer. “That’s what Google does. We’re not Google.”
If you’d like to study pumping physics on your own, you can tune in to the Paris Olympics. The women skateboarders are scheduled to compete in the park event (as opposed to the street event, which has fewer curved surfaces for pumping) Tuesday morning. The men are scheduled for Wednesday.
McKenna has always seen skating more as an art form and community than a sport, but he’s stoked to watch nonetheless. “When I was a kid, which doesn’t seem that long ago, skateboarding was a crime, literally,” he said. “Now we’re winning gold medals in the Olympics.”
Science
AI windfall helps California narrow projected $3-billion budget deficit
SACRAMENTO — California and its state-funded programs are heading into a period of volatile fiscal uncertainty, driven largely by events in Washington and on Wall Street.
Gov. Gavin Newsom’s budget chief warned Friday that surging revenues tied to the artificial intelligence boom are being offset by rising costs and federal funding cuts. The result: a projected $3-billion state deficit for the next fiscal year despite no major new spending initiatives.
The Newsom administration on Friday released its proposed $348.9-billion budget for the fiscal year that begins July 1, formally launching negotiations with the Legislature over spending priorities and policy goals.
“This budget reflects both confidence and caution,” Newsom said in a statement. “California’s economy is strong, revenues are outperforming expectations, and our fiscal position is stable because of years of prudent fiscal management — but we remain disciplined and focused on sustaining progress, not overextending it.”
Newsom’s proposed budget did not include funding to backfill the massive cuts to Medicaid and other public assistance programs by President Trump and the Republican-led Congress, changes expected to lead to millions of low-income Californians losing healthcare coverage and other benefits.
“If the state doesn’t step up, communities across California will crumble,” California State Assn. of Counties Chief Executive Graham Knaus said in a statement.
The governor is expected to revise the plan in May using updated revenue projections after the income tax filing deadline, with lawmakers required to approve a final budget by June 15.
Newsom did not attend the budget presentation Friday, which was out of the ordinary, instead opting to have California Director of Finance Joe Stephenshaw field questions about the governor’s spending plan.
“Without having significant increases of spending, there also are no significant reductions or cuts to programs in the budget,” Stephenshaw said, noting that the proposal is a work in progress.
California has an unusually volatile revenue system — one that relies heavily on personal income taxes from high-earning residents whose capital gains rise and fall sharply with the stock market.
Entering state budget negotiations, many expected to see significant belt tightening after the nonpartisan Legislative Analyst’s Office warned in November that California faces a nearly $18-billion budget shortfall. The governor’s office and Department of Finance do not always agree, or use the LAO’s estimates.
On Friday, the Newsom administration said it is projecting a much smaller deficit — about $3 billion — after assuming higher revenues over the next three fiscal years than were forecast last year. The gap between the governor’s estimate and the LAO’s projection largely reflects differing assumptions about risk: The LAO factored in the possibility of a major stock market downturn.
“We do not do that,” Stephenshaw said.
Among the key areas in the budget:
Science
California confirms first measles case for 2026 in San Mateo County as vaccination debates continue
Barely more than a week into the new year, the California Department of Public Health confirmed its first measles case of 2026.
The diagnosis came from San Mateo County, where an unvaccinated adult likely contracted the virus from recent international travel, according to Preston Merchant, a San Mateo County Health spokesperson.
Measles is one of the most infectious viruses in the world, and can remain in the air for two hours after an infected person leaves, according to the CDPH. Although the U.S. announced it had eliminated measles in 2000, meaning there had been no reported infections of the disease in 12 months, measles have since returned.
Last year, the U.S. reported about 2,000 cases, the highest reported count since 1992, according to CDC data.
“Right now, our best strategy to avoid spread is contact tracing, so reaching out to everybody that came in contact with this person,” Merchant said. “So far, they have no reported symptoms. We’re assuming that this is the first [California] measles case of the year.”
San Mateo County also reported an unvaccinated child’s death from influenza this week.
Across the country, measles outbreaks are spreading. Today, the South Carolina State Department of Public Health confirmed the state’s outbreak had reached 310 cases. The number has been steadily rising since an initial infection in July spread across the state and is now reported to be connected with infections in North Carolina and Washington.
Similarly to San Mateo’s case, the first reported infection in South Carolina came from an unvaccinated person who was exposed to measles while traveling internationally.
At the border of Utah and Arizona, a separate measles outbreak has reached 390 cases, stemming from schools and pediatric centers, according to the Utah Department of Health and Human Services.
Canada, another long-standing “measles-free” nation, lost ground in its battle with measles in November. The Public Health Agency of Canada announced that the nation is battling a “large, multi-jurisdictional” measles outbreak that began in October 2024.
If American measles cases follow last year’s pattern, the United States is facing losing its measles elimination status next.
For a country to lose measles-free status, reported outbreaks must be of the same locally spread strain, as was the case in Canada. As many cases in the United States were initially connected to international travel, the U.S. has been able to hold on to the status. However, as outbreaks with American-origin cases continue, this pattern could lead the Pan American Health Organization to change the country’s status.
In the first year of the Trump administration, officials led by Health Secretary Robert F. Kennedy Jr. have promoted lowering vaccine mandates and reducing funding for health research.
In December, Trump’s presidential memorandum led to this week’s reduced recommended childhood vaccines; in June, Kennedy fired an entire CDC vaccine advisory committee, replacing members with multiple vaccine skeptics.
Experts are concerned that recent debates over vaccine mandates in the White House will shake the public’s confidence in the effectiveness of vaccines.
“Viruses and bacteria that were under control are being set free on our most vulnerable,” Dr. James Alwine, a virologist and member of the nonprofit advocacy group Defend Public Health, said to The Times.
According to the CDPH, the measles vaccine provides 97% protection against measles in two doses.
Common symptoms of measles include cough, runny nose, pink eye and rash. The virus is spread through breathing, coughing or talking, according to the CDPH.
Measles often leads to hospitalization and, for some, can be fatal.
Science
Trump administration declares ‘war on sugar’ in overhaul of food guidelines
The Trump administration announced a major overhaul of American nutrition guidelines Wednesday, replacing the old, carbohydrate-heavy food pyramid with one that prioritizes protein, healthy fats and whole grains.
“Our government declares war on added sugar,” Health and Human Services Secretary Robert F. Kennedy Jr. said in a White House press conference announcing the changes. “We are ending the war on saturated fats.”
“If a foreign adversary sought to destroy the health of our children, to cripple our economy, to weaken our national security, there would be no better strategy than to addict us to ultra-processed foods,” Kennedy said.
Improving U.S. eating habits and the availability of nutritious foods is an issue with broad bipartisan support, and has been a long-standing goal of Kennedy’s Make America Healthy Again movement.
During the press conference, he acknowledged both the American Medical Association and the American Assn. of Pediatrics for partnering on the new guidelines — two organizations that earlier this week condemned the administration’s decision to slash the number of diseases that U.S. children are vaccinated against.
“The American Medical Association applauds the administration’s new Dietary Guidelines for spotlighting the highly processed foods, sugar-sweetened beverages, and excess sodium that fuel heart disease, diabetes, obesity, and other chronic illnesses,” AMA president Bobby Mukkamala said in a statement.
-
Detroit, MI1 week ago2 hospitalized after shooting on Lodge Freeway in Detroit
-
Technology5 days agoPower bank feature creep is out of control
-
Dallas, TX3 days agoAnti-ICE protest outside Dallas City Hall follows deadly shooting in Minneapolis
-
Delaware3 days agoMERR responds to dead humpback whale washed up near Bethany Beach
-
Dallas, TX7 days agoDefensive coordinator candidates who could improve Cowboys’ brutal secondary in 2026
-
Iowa5 days agoPat McAfee praises Audi Crooks, plays hype song for Iowa State star
-
Health1 week agoViral New Year reset routine is helping people adopt healthier habits
-
Montana1 day agoService door of Crans-Montana bar where 40 died in fire was locked from inside, owner says