- Press Release Distribution

Elite runners spend more time in air, less on ground, than highly trained but nonelite peers

( A recent study led by Geoff Burns, an elite runner and postdoctoral researcher at the University of Michigan Exercise & Sport Science Initiative, compared the "bouncing behavior"--the underlying spring-like physics of running--in elite-level male runners (sub-four-minute milers) vs. highly trained but not elite runners.

Subjects ran on a treadmill instrumented with a pressure plate beneath the belt, so Burns and colleagues could see how much time they spent in the air and in contact with the ground. When running, muscles and limbs coordinate to act like a giant pogo stick, and those muscles, tendons and ligaments interact to recycle energy from step to step, Burns says.

The researchers looked at the basic physics of the runners as pogo sticks--called a "spring-mass" system in biomechanics--to see how those giant springs differed between elite and highly trained runners, and found some interesting and surprising differences.

What did you find?

We often think of running as pushing off the ground, but it's actually a beautifully coordinated bounce. All animals that run behave like this--even the ones with multiple pairs of legs coordinating to "bounce" along the ground.

In general, the elite runners were "stiffer" spring-mass systems with steeper impact angles--think of stiffer, more upright pogo sticks. Across various speeds, the elites had similar stride lengths and stride frequencies (similar cadences, or steps-per-minute) as highly trained runners, but elites spent more time in the air and less on the ground, especially at the lower speeds. With their "stiffer" spring behavior on each step, they may be better recycling that gravitational energy from the time in the air to quickly and efficiently bounce along, step-to-step.

One of the key findings was that difference in speeds. Across all speeds, the elite runners were in the air longer, but both time on the ground and in the air changed differently across speeds in the two groups. In both measures, the highly trained group approached the elites at faster speeds, but at lower speeds--where both groups spend the bulk of training time--the times were very divergent, with the elites more similar to their patterns at faster speeds.

In your study, you write that the interaction of nature and nurture--not one or the other--may give rise to their emergent, elite ability. Can you explain?

I suspect for each runner it operates on a spectrum. There are aspects of nature, or at least aspects that are developed very early on, such as tendon properties or neuromuscular recruitment patterns. But those things, and other contributing factors to these "system" characteristics of a runner's bouncing patterns, can be developed to some extent. It's probable that an interaction of nature and nurture allowed certain people to take to the training and racing that further developed the characteristics of an elite runner.

How did your own talent emerge? Was there a time when it became clear that you had special abilities?

I think my intrinsic physical qualities that allowed me to excel were my more malleable physiology and capacity to absorb training, meaning an ability to get better (perhaps, a nature that is readily nurtured). That ability to adapt and improve coupled with an intense desire and drive to do so is a good combo. So, with respect to mechanics, that may have manifested as the ability to adopt the characteristics that my competition-specific training and preparation demanded. I suspect I'm fortunate to have this capacity more than most, but I also think it should hopefully inspire everyone who runs, that these things aren't likely entirely predetermined. We, as humans, have the capacity to change ourselves with the right stimulus to adopt characteristics, be it mechanical or physiological, that allow us to achieve better performances.

Is there a practical application for runners here? Can this be taught?

Yes, these aspects are--to some extent--trainable. Things like resistance training for the lower limbs are known to increase leg stiffness, and even incorporating plyometric drills can help with this. Even something as simple as running on different surfaces (pavement vs. grass vs. dirt) will force you to change your body's bouncing stiffness. Simply put, challenging your body to interact with the ground differently will likely promote some sort of beneficial adaptation, if dosed responsibly.

But, I would certainly caution runners from trying to change this consciously. By this I mean, don't go out for a run and think, "I'm going to run with a stiffer leg or body" or "I'm going to try and spend as little time on the ground and as much time in the air as possible for this whole run." Broadly speaking, when we run, our bodies choose the movement patterns that tend to be most efficient and safest for us at that time. Moreover, because these are "system" characteristics, trying to exert conscious control over a continuously changing coordination of components is a recipe for trouble.

Putting those two things together, I'd say runners shouldn't try to consciously change their system or emulate the elite characteristics, but rather incorporate elements in their training that demand their system to take on those characteristics. What are those things? I think we can look right at the common ingredients of the middle distance runners' training menu: hills, sprints and fast intervals, plyometric drills, and lots of easy, slower running. These are things that are easy to incorporate into training that will challenge the whole "system" of a runner--be it the musculoskeletal strength, those neuromuscular coordination patterns, or tendinous structures--all to interact with the ground more efficiently across a range of speeds. While most of both the trained and elite runners in our study used these ingredients to some extent, I would add that the elites were certainly more regimented in them, and most incorporated resistance training as well.

Did anything about the findings surprise you?

The different relations with speed between the two groups in the contact time and flight time were interesting. I expected those variables to be linked to speed in both groups, and maybe some general difference between the two, but the interaction was interesting. Especially in that the elite group was less influenced by speed, meaning those patterns persisted at slower speeds. This could suggest a robustness of the musculoskeletal and physiological patterns that give rise to the overall spring-like characteristics of their stride, or that they're continually training these patterns at lower speeds when they're not incurring the physiological and mechanical stresses of running at faster speeds. That's just my own speculation, but it was very interesting.

It was also interesting that despite these different patterns in the speed dependency between the two groups, the runners still coordinated their global mechanics to maintain consistent leg stiffness across all speeds. This was expected, as all running animals tend to maintain leg stiffness across speeds (which was cool, nonetheless, to see that play out here in all the runners). But that there were different relationships with the other variables across speeds between the two groups that ultimately produced this consistent bouncing behavior in each group was pretty neat. And that it was consistently higher in the elites was further cool.

It was also interesting that the two groups had similar vertical compressions during stance across speeds, meaning that their bodies moved up and down similar amounts, yet the net result was still higher leg stiffnesses and vertical stiffnesses. This stems from the interaction of the steeper impact angles in the elites and the higher vertical forces. So, they were more upright in their force delivery to the ground, and loaded their bodies slightly more. Ultimately, they moved up and down the same amount, but because the forces were greater and their mechanical system was stiffer, they could recycle more energy through the stance cycle.

Did any one or two elements of movement stand out as being more significant than others?

In addition to the ones discussed above (contact and flight relations, vertical compression), the impact angle patterns were also interesting. These are essentially a synthesis of the runner's time on the ground, the runner's speed and the body's geometry. That the runners converged on the contact time at faster speeds but diverged on the impact angle (meaning the elites and subelites had more similar contact times at faster speeds, but less similar impact angles) would suggest that the two groups were changing their contact times in relation to their center-of-mass height and leg length differently, with the elites doing so to keep their system more "upright" or vertical at the faster speeds.

Do you plan to study female runners?

I do hope to publish something very similar in the coming year on groups of elite and highly trained female runners. I'm very curious to see how the trends between groups compare, but also how the characteristics at common speeds are similar or different.


Study co-authors include: Richard Gonzalez, U-M professor of psychology, marketing and statistics; Jessica Zendler, a researcher at the Michigan Performance Research Laboratory and principal consultant at Zendler Scientific, a consulting and research services firm for sport and human performance; and Ronald Zernicke, director of U-M's Exercise & Sport Science Initiative and professor of kinesiology, biomedical engineering and orthopaedic surgery.

The study, " END


Health care providers missing opportunities to talk about sexual health with young people

Routine adolescent preventive visits provide important opportunities for promoting sexual and reproductive health and for preventing unintended pregnancy and sexually transmitted infections. A new study END ...

Mind and matter: Modeling the human brain with machine learning

We all like to think that we know ourselves best, but, given that our brain activity is largely governed by our subconscious mind, it is probably our brain that knows us better! While this is only a hypothesis, researchers from Japan have already proposed a content recommendation system that assumes this to be true. Essentially, such a system makes use of its user's brain signals (acquired using, say, an MRI scan) when exposed to a particular content and eventually, by exploring various users and contents, builds up a general model of brain activity. "Once we obtain the 'ultimate' brain model, we should be able to perfectly estimate the brain activity of ...

American Board of Urology outlines processes to ensure diversity in leadership

July 19, 2021 - At the organization responsible for certifying the training and skills of US urologists, achieving and maintaining diversity, equity and inclusion is more than just a "numbers game," according to a special article in Urology Practice®, an Official Journal of the American Urological Association (AUA). The journal is published in the Lippincott portfolio by Wolters Kluwer. In the new article, the American Board of Urology (ABU) points out that the practice of diversity and inclusion has been a cornerstone of its values for years. However, the Board acknowledges that while progress has been made, ...

Public trust in CDC, FDA, and Fauci holds steady, survey shows

Public trust in CDC, FDA, and Fauci holds steady, survey shows
With more than two-thirds of American adults vaccinated with at least one dose of an authorized Covid-19 vaccine, the top U.S. health agencies retain the trust of the vast majority of the American public, as does Dr. Anthony Fauci, the public face of U.S. efforts to combat the virus, according to a new survey from the Annenberg Public Policy Center (APPC) of the University of Pennsylvania. The survey revealed growing public confidence in both the safety and effectiveness of vaccines to prevent Covid-19. But after months of attacks on Fauci in conservative and social media, the survey found that people who said they rely on conservative and very conservative media rather than other sources ...

New insight into "training" highly reactive chemical compounds

New insight into training highly reactive chemical compounds
Led by Dr Jonas Warneke, researchers at the Wilhelm Ostwald Institute of Physical and Theoretical Chemistry at Leipzig University have made a decisive advance in the study of one type of highly reactive particles. Based on their research, they now understand the "binding preferences" of these particles. Their research serves as the basis for the targeted use of these highly reactive molecules, for example, to generate new molecular structures or to bind hazardous chemical "waste" and in this way dispose of it. The researchers have now published their findings in the journal Chemistry - A European Journal, and their research was featured on the cover thanks to the excellent review they received. What molecules and people have in common Molecules and people actually have a lot in ...

15,000-year-old viruses discovered in Tibetan glacier ice

15,000-year-old viruses discovered in Tibetan glacier ice
COLUMBUS, Ohio - Scientists who study glacier ice have found viruses nearly 15,000 years old in two ice samples taken from the Tibetan Plateau in China. Most of those viruses, which survived because they had remained frozen, are unlike any viruses that have been cataloged to date. The findings, published today in the journal Microbiome, could help scientists understand how viruses have evolved over centuries. For this study, the scientists also created a new, ultra-clean method of analyzing microbes and viruses in ice without contaminating it. "These glaciers were formed gradually, and along with dust and ...

Automobile class society

In order to correctly separate vehicles into classes, for instance for mobility pricing, one must be able to clearly distinguish mid-sized cars from upper class cars or small cars from compact cars. But this is becoming increasingly difficult: On photos, an Audi A4 looks almost the same as an Audi A6, a Mini One looks similar to a Mini Countryman. To date, there is no independent procedure for doing this. Thus far, the classes in each country have been determined by experts - to a large extend at their own discretion. Empa researcher Naghmeh Niroomand has now developed a system that can classify cars worldwide based on their dimensions. Purely mathematical and fair. Thanks to it, the current classification ...

Fish friends help in a crisis

Fish friends help in a crisis
FORT LAUDERDALE/DAVIE, Fla. - It's good to have friends. Most humans have experienced social anxiety on some level during their lives. We all know the feeling - we show up to a party thinking it is going to be chock full of friends, only to find nearly all total strangers. While we typically attribute the long-lasting bonds of social familiarity to complex thinkers like humans, growing evidence indicates that we underestimate the importance of friendship networks in seemingly "simple" animals, like fish, and its importance for survival in the wild. To better understand how familiarity impacts social fishes, a group of research scientists studied this idea using schooling coral reef fish. "We studied how the presence of ...

SARS-CoV-2: Achilles' heel of viral RNA

FRANKFURT, GERMANY. When SARS-CoV-2 infects a cell, it introduces its RNA into it and re-programmes it in such a way that the cell first produces viral proteins and then whole viral particles. In the search for active substances against SARS-CoV-2, researchers have so far mostly concentrated on the viral proteins and on blocking them, since this promises to prevent, or at least slow down, replication. But attacking the viral genome, a long RNA molecule, might also stop or slow down viral replication. The scientists in the COVID-19-NMR consortium, which is coordinated by Professor Harald Schwalbe from the Institute of Organic Chemistry and Chemical Biology at Goethe University, have now completed an important ...

The environmental toll of disposable masks

CAMBRIDGE, MA -- Since the Covid-19 pandemic began last year, face masks and other personal protective equipment have become essential for health care workers. Disposable N95 masks have been in especially high demand to help prevent the spread of SARS-CoV-2, the virus that causes Covid-19. All of those masks carry both financial and environmental costs. The Covid-19 pandemic is estimated to generate up to 7,200 tons of medical waste every day, much of which is disposable masks. And even as the pandemic slows down in some parts of the world, health care workers are expected to continue wearing masks most of the time. That toll could be dramatically cut by adopting reusable masks, according to a new study from MIT that has calculated the financial ...


Scientists model 'true prevalence' of COVID-19 throughout pandemic

New breakthrough to help immune systems in the fight against cancer

Through the thin-film glass, researchers spot a new liquid phase

Administering opioids to pregnant mice alters behavior and gene expression in offspring

Brain's 'memory center' needed to recognize image sequences but not single sights

Safety of second dose of mRNA COVID-19 vaccines after first-dose allergic reactions

Changes in disparities in access to care, health after Medicare eligibility

Use of high-risk medications among lonely older adults

65+ and lonely? Don't talk to your doctor about another prescription

Exosome formulation developed to deliver antibodies for choroidal neovascularization therapy

Second COVID-19 mRNA vaccine dose found safe following allergic reactions to first dose

Plant root-associated bacteria preferentially colonize their native host-plant roots

Rare inherited variants in previously unsuspected genes may confer significant risk for autism

International experts call for a unified public health response to NAFLD and NASH epidemic

International collaboration of scientists rewrite the rulebook of flowering plant genetics

Improving air quality reduces dementia risk, multiple studies suggest

Misplaced trust: When trust in science fosters pseudoscience

Two types of blood pressure meds prevent heart events equally, but side effects differ

New statement provides path to include ethnicity, ancestry, race in genomic research

Among effective antihypertensive drugs, less popular choice is slightly safer

Juicy past of favorite Okinawan fruit revealed

Anticipate a resurgence of respiratory viruses in young children

Anxiety, depression, burnout rising as college students prepare to return to campus

Goal-setting and positive parent-child relationships reduce risk of youth vaping

New research identifies cancer types with little survival improvements in adolescents and young adul

Oncotarget: Replication-stress sensitivity in breast cancer cells

Oncotarget: TERT and its binding protein: overexpression of GABPA/B in gliomas

Development of a novel technology to check body temperature with smartphone camera

The mechanics of puncture finally explained

Extreme heat, dry summers main cause of tree death in Colorado's subalpine forests

[] Elite runners spend more time in air, less on ground, than highly trained but nonelite peers