Tag Archives: Running

Does listening to music improve running performance?

Credit: Pixabay.

For many runners, a pair of headphones is more important than the best running gear out there. Listening to your favorite tunes while working out can make training more enjoyable, but beyond the subjective experience, is there any evidence that music can actually help you run more or faster? As a matter of fact, yes.

There are quite a number of studies that support using music to get fired up before and during running. In a 2015 study led by Marcelo Bigliassi, an expert in psychophysiology and neuroscience from Florida International University, 15 well-trained male long-distance runners participated in five experiments. The effects of music on the performance during a 5-km run were assessed in four contexts: pre-run motivational music (110-150 beats per minute); running with slow music (80-100 beats per minute); running with fast music (140-160 beats per minute); post-run calming music (95-110 beats per minute). The participants also ran a 5-km trail with no music, as a control.

The researchers measured pre-run brain activity, arousal, and heart rate variability; perceived effort and completion time during the run, and post-run mood and heart rate viability.

According to the results, listening to “motivational music” before the run aroused the runners, charging them up for the 5-km trail run. During the run itself, the participants who listened to music completed the first two laps faster than those who ran without music. However, the differences in lap times between the two groups greatly decreased with each loop.

That’s consistent with other studies that showed the higher the required intensity of effort, the less effect music has on performance.

“Although some people may experience performance detriments while exercising in the presence of music, the majority of individuals tend to benefit from the use of music during sport- and exercise-related tasks,” Dr. Bigliassi told MetaFact.

In another study conducted by researchers at the Texas A&M University-Corpus Christi, the effect of music listening on running performance and perceived exertion was assessed in a cohort of 28 undergraduate students. The students had to complete a relatively short 2.5-km run either while listening to music or without.

“The results of this study indicate that music listening has a significant effect on running performance during a maximal 1.5-mile run. However, music listening had no significant effect on the rating of perceived exertion at this distance,” the researchers found.

While these results suggest that listening to music doesn’t have an effect on perceived exertion, a recent study conducted at the University of Edinburgh found that music improved training performance when you’re already mentally fatigued. Music may also help when running conditions are difficult. A 2018 study that appeared in the journal Frontiers in Psychology had volunteers run on a treadmill in hot and humid conditions. Those who did so while listening to music ran 67% longer than the non-music control group before they felt exhausted.

“Music listening during sports and exercise is believed to capture attention, distract from fatigue and discomfort, prompt and alter mood states, enhance work output, increase arousal, relieve stress, stimulate rhythmic movement, and evoke a sense of power and produce power-related cognition and behavior,” Edith Van Dyck, an expert in musicology and psychology from Ghent University in Belgium, told MetaFact.

Van Dyck added that music in the same tempo of the exercise or slightly higher rendered the most optimal performance. But since music preference is so subjective, the best workout music is often whatever your favorite playlist happens to be. What’s more, for some, listening to music actually hampers their performance.

According to Dr. Costas Karageorghis, an expert on the effects of music on exercise, at Brunel University, elite athletes have the least to gain from training while listening to music. That’s because they’re, what Karageorghis calls, ‘associators’, meaning they focus inwardly when running. Amateur athletes, on the other hand, are ‘dissociators’ who are more susceptible to external stimuli and distractions, so music can help nudge them when they aren’t feeling motivated.

Perhaps a bit too hyperbolically, Karageorghis says “music is a legal drug for athletes” but “like any drug, if you use it too much, it begins to have less effect.” This is why he recommends saving music for the end of your run, so it acts like a boost, he told The Guardian.

Adult T-Rexs likely couldn’t keep up with their offspring, judging from their paw prints

Could T. rex keep up with its kids? New research says ‘no’.

Image credits Brickset / Flickr.

Researchers at the University of New England’s (UNE) Paleoscience Research Centre found that young tyrannosaurs were much faster than their parents, suggesting that the adults could have had actual trouble keeping up with their young. It likely all came down to the significant difference in body size between adults and juveniles, the team explains.

The findings are based on a collection of fossilized tyrannosaur footprints which helped record how these animals moved throughout their different developmental stages.

Bigger, harder, stronger, slower

“Fully grown tyrannosaurs were believed to be more robust than younger individuals based on their relatively shorter hind limbs and more massive skulls, but nobody had explored this growth pattern using fossil footprints, which are unique in that they can provide a snapshot of the feet as they appeared in life, with outlines of the soft, fleshy parts of the foot that are rarely preserved as fossils,” said UNE PhD student and lead author of the paper, Nathan Enriquez.

“The results suggest that as some tyrannosaurs grew older and heavier, their feet also became comparably more bulky,” he adds, which would reduce their top speed.

There are a lot of elements that influence the final shape of a footprint. Things like soil composition and properties, the exact position of the animal as the print was made, the geography of the surface (and a lot of others) will influence the final shape that is imparted to a surface. Unsurprisingly, this makes interpreting footprints, especially fossilized ones, a very difficult process that’s fraught with pitfalls. Due to this, fossilized tracks haven’t been used extensively to understand dinosaur growth.

This set of footprints, however, from the Grande Prairie region of Northern Alberta, Canada, were found in very good condition and sported prints that belonged to individuals of the same species but different sizes.

“Based on the relatively close proximity between these discoveries and their nearly equivalent ages — about 72.5 million years old — we suggest they may indeed belong to the same species,” says Enriquez.

“We were also careful to assess the quality of preservation in each footprint, and only considered specimens which were likely to reflect the shape of the actual feet that produced them.”

After establishing which of the prints were suitable for their research, the team analyzed their outline using an approach called geometric morphometrics. This was meant to look past the differences in overall size between the tracks, and spot the key differences in shape between these tracks.

The most important difference in shape they found was the width and surface area of the heel relative to the overall imprint size. This ratio was significantly lower in the smaller prints. The team explains that the smaller tracks were “slender”, while the larger ones were “broader” and had larger heel areas. This increase was needed as the animal increased in size as it aged, as their legs needed to be able to physically support their bulk, but it also suggests that older individuals weren’t able to reach the same speeds as their young.

“Increasingly bulky feet in the adults aligns with previous suggestions that juvenile tyrannosaurs would have been faster and more agile for their body size in comparison to their parents, and means that we can add footprints as another line of evidence in the debate over tyrannosaur growth,” Enriquez notes.

One of the most exciting parts of science, for me personally, is that if you understand how the different parts of a picture fit together, you can then draw conclusions from seemingly unrelated elements — such as judging how fast an animal was able to go based on its pawprints.

Since we don’t have many reliable sources of data regarding long-extinct species such as T. rex, any sliver of information we can get is priceless. The current paper offers up one such tidbit which will help us better understand how the dinosaur’s abilities and ways of life changed as it aged. Hopefully, such an approach will be refined in the future to make it more reliable and widely-applicable, and that it will be used on prints from other dinosaur species as well.

The paper “Exploring possible ontogenetic trajectories in tyrannosaurids using tracks from the Wapiti Formation (upper Campanian) of Alberta, Canada” has been published in the Journal of Vertebrate Paleontology.

To run a marathon, you don’t need superhuman abilities — you need efficiency and resilience

It was a cold misty morning in Vienna when Eliud Kipchoge made history. The Kenyan runner finished an unofficial marathon in a once-inconceivable time: 1 hour 59 minutes and 40 seconds for the 26.2 miles (42.6 kilometers).

You’d be excused for thinking that Kipchoge is some form of superhuman performer. For most of us, even finishing a marathon seems like a far-fetched dream. But while this under-two-hour performance is groundbreaking, you don’t really need superhuman abilities to finish a marathon in good time, a new study has shown.

Credit Flickr Hans Splinter

“Athletics is not so much about the legs. It’s about the heart and mind,” Kipchoge once said, and he was pretty on point. The key to a good marathon is not in the legs — it’s in the lungs.

Whenever we exercise or run, we start to breathe more heavily. That’s because our body requires more oxygen to power our muscles; the more we intensify our workout, the more heavily we breathe. There’s a limit to this: it’s called VO2 max, or the maximum volume of oxygen you can use. This VO2 max also isn’t fixed in time, you can improve it by being active and constantly pushing your limits, but it can also drop if you lead a sedentary lifestyle.

A study carried out by University of Exeter researchers in collaboration with Nike analyzed the VO2 max and other physiological requirements that are necessary to run a two-hour marathon — but the findings apply to more than just elite athletes, they also apply to regular people.

For the study, the researchers analyzed the outdoor running test of 16 athletes in the selection stage of Breaking2, a project by Nike to break the two-hour barrier of a marathon, accomplished by Kipchoge in 2019. They found that a 59kg runner would need to take in about four liters of oxygen per minute to maintain a two-hour marathon pace (21.1 km/h).

At marathon pace, elite runners can take in oxygen twice as fast as a “normal” person of the same age and weight, even when sprinting, according to VO2 measurements. Still, this difference wasn’t as striking as high as researchers initially expected. Runners actually need to have several characteristics for a good marathon performance, it’s not just the VO2 max.

Another important parameter is the so-called “lactate threshold”: the intensity after which lactic acid starts to quickly accumulate (and which consequently makes you more fatigued). The lactate threshold is often defined as 85% of maximum heart rate, and elite athletes seem to have developed a sense navigating under this threshold.

Runners with better performances also need a good running “economy”. This means that the body must use oxygen efficiently, both internally and through effective running action. Having all these features (VO2 max, lactate threshold, economy) is basically what you need to achieve a good performance in any given race.

“The runners we studied – 15 of the 16 from East Africa – seem to know intuitively how to run just below their ‘critical speed’, close to the ‘lactate turn point’ but never exceeding it,” Professor Andrew Jones, lead author of the study, said in a statement. “This is especially challenging because – even for elite runners – the turn point drops slightly over the course of a marathon.”

So in a sense, Kipchoge was right: it’s not really about the legs. You need a good heart, good lungs, and a healthy mindset to go through the effort efficiently. Whether or not you’re planning on running a marathon anytime soon, that’s a lesson worth remembering.

The study was published in the Journal of Applied Physiology.

Social distancing of 1.5 meters (5 feet) might not really be enough — especially when running or biking

Exercising is one of the few things we’re still allowed to do in quarantine, but it may carry more risks than anticipated, a team of Belgian and Dutch researchers warn.

However, there are many issues with this analysis. For starters, the researchers chose to bypass standard scientific publishing, detailing only their findings and not their methodology or how the results were reached.

Multidisciplinary understanding

via GIPHY

When it comes to understanding how a disease is transmitted, it’s not just about medicine and biology. For instance, material scientists can help us understand what face masks offer better protection, and engineers can find new ways to improvise ventilators that can save people’s lives. Similarly, aerodynamicists can help us understand just how the disease gets passed around from one person to the other.

The reason why aerodynamics is so important here is that SARS-CoV-2, the virus causing COVID-19, is passed through droplets. If we want to understand how it is transmitted, we first need to understand how these droplets can be transmitted in day to day situations.

In a simulation that is admittedly preliminary, unproven, and not peer-reviewed, a team of aerodynamicists presented new findings that suggest such droplets can easily be passed over a distance longer than the usually-recommended 1.5 meters — especially if you’re walking, running, or cycling.

“If someone exhales, coughs or sneezes while walking, running or cycling, most of the microdroplets are entrained in the wake or slipstream behind the runner or cyclist. The other person who runs or cycles just behind this leading person in the slipstream then moves through that cloud of droplets,”says Bert Blocken, professor of civil engineering at Eindhoven University of Technology and KU Leuven

There is much to be said about this analysis — including the fact that we don’t really know how reliable it is, how, exactly, the results were obtained, and why it was published in the manner it was. We’ll get to that in a bit.

What the simulation showed

The researchers simulated the occurrence of saliva particles an average person would generate during movement (walking and running), and in different positions, simulating it with specialized algorithms.

This type of study is routinely used to help athletes improve their performance level or deploy a position that is more aerodynamic. But it can also reveal how droplets pass through the air.

Image credits: TU Eindhoven and KU Leuven.

The simulations showed that when people walk or run side by side in calm weather, the droplets tend end up behind the two, and there is little risk of contamination.

The greatest risk of contamination is when people walk or run behind each other, in each other’s slipstream (the region behind a moving object or person in which a wake of fluid is moving at velocities comparable to the moving object).

Furthermore, when you’re overtaking someone (whether it’s through walking, running, or cycling), you need to be sure that first of all, you don’t stand behind that person’s slipstream, and after you overtake them, you don’t put them in your slipstream.

A good way to think about it is: you need to overcome someone the same way you’d do if you were driving a car. Get on a different trajectory early on, leave a healthy gap, and don’t wait until the last moment (that’s a good idea in general, not just in a pandemic).

Based on the results, Blocken advises keeping a distance of at least four to five meters behind the leading person while walking in the slipstream, ten meters when running or cycling slowly, and at least twenty meters when cycling fast.

Scathing criticism

Blocken hasn’t published his study or his methodology yet. We don’t know exactly how the results were obtained and how the slipstream itself was modeled — and there are big questions to clarify.

For instance, a 2016 MIT study found that sneezing doesn’t produce a simple spray of particles, but rather a complex fluid cascade, and therefore needs to be modeled accordingly. What does this mean for heavy breathing? We don’t really know, and it’s a problem.

There is also the matter of designing the flow of the particles: if a simple simulation starts from the nostrils, it is probably missing out an important part, as the particles actually start out in the lungs and this affects their journey out of the nostrils. Did this simulation start in the lungs or in the nostrils? We don’t know. There are plenty of good simulations on sneezing and breathing, but it’s a very complex procedure that needs to be justified thoroughly, writes Stephen Ferguson, a Computational Fluid Dynamics Engineer in a scathing post.

So it’s hard to say just how reliable the sneezing and coughing simulations are, especially when also considering the virology aspect. In normal times, no scientist worth his salt would have published this type of simulation without offering the details.

But these are not normal times.

Scientific publishing takes months and months, and while medical journals have greatly accelerated that process, we’re not sure if the same happens for aerodynamics journals.

We’re facing an urgent situation. It’s more important than ever to bring science to the public quickly — but it’s also important to ensure that we don’t get any bad science out there to confuse things even more. The thing is, at this moment, there are many specifics we don’t know about this study, and while it’s important to get this type of science out, it’s also important to look at how the data was obtained before we start making any recommendations for policymakers or joggers.

The bottom line is that it’s understandable that researchers from all fields want to help. We need this type of study, and we need to better understand how the coronavirus can spread, but we also need rigorous evidence.

It doesn’t hurt to leave a bigger gap between yourself and other walkers or runners. Does it reduce your risks of contracting the disease? We’re not sure. But it’s harmless, and at the very least, it might make you feel a bit safer going outside — and that’s something all of us need at this moment.

Running, even just a little, can reduce your risk of death

You can’t run away from your problems — unless, it turns out, that problem is death.

Image via Pixabay.

Any amount of running is linked to a significantly lower risk of death from any cause, a new metastudy on the subject reports. If more people took up running, the authors add, we could see substantial improvements in population health and longevity.

Run, Forest, run

That physical exercise is good for you isn’t exactly news. However, the exact details on running are a bit fuzzy. The full extent of its benefits on our health is not exactly clear, even if we know that it does protect us from cardiovascular diseases, for example. It’s not clear how much a person should run to see the potential benefits, or whether running more frequently, for longer, or at a certain pace brings certain benefits over other styles of running.

In a bid to find out, the team performed a systematic review of all relevant published studies, conference presentations, doctoral theses, and dissertations. The team was on the lookout for research into the link between running, jogging, and the risk of death from all causes, cardiovascular disease, and cancer.

The team whittled the databases down to 14 suitable studies involving 232,149 people. The participants of the studies used were tracked for periods ranging from 5.5 years up to 35 years. The team also reports that 25,951 of the study participants died as their respective studies were ongoing. After the data was pooled together, they showed that any amount of running was associated with a 27% lower risk of death from all causes for both sexes compared to no running. Running was also associated with a 30% lower risk of death from cardiovascular disease and a 23% lower risk of death from cancer.

The team further explains that even casual running — for example once per week or less, lasting less than 50 minutes each time, even at speeds under 6 mi (8 km) an hour — was still associated with significant health benefits and longevity. That’s 25 minutes less than the recommended weekly amount of vigorous exercise.

All in all, this suggests running is a very good option for people whose main obstacle to exercising is a lack of time. On the flip side, however, the team reports that more running (above the threshold mentioned above) didn’t lead to greater reductions in the risk of death from any cause.

Please keep in mind that this is an observational study — it can find a link between two factors, but it cannot establish any cause-effect relationships between them. More plainly, while the study finds that people who run have better odds of not dying, it can’t say whether running is the cause and ‘not dying’ the effect. It may simply be that people who engage in running are more health-conscious overall, which makes them less likely to die from any cause. Alternatively, it can be that people who run tend to be more self-conscious overall, taking better care of themselves, which makes them less likely to die from any cause. Still, the team says that even a little running is better than no running.

“Increased rates of participation in running, regardless of its dose, would probably lead to substantial improvements in population health and longevity,” the study concludes

The paper “Systematic review: Is running associated with a lower risk of all-cause cardiovascular and cancer mortality, and is the more the better? A systematic review and meta-analysis” has been published in the British Journal of Sports Medicine.

Caudipteryx robot.

Feathered dinosaurs may have accidentally developed flying — while running

Flying is a pretty nifty way of moving around very fast. New research is looking into the dinosaurs’ earliest attempts at flight, an effort which ultimately led to the birds of today.

Caudipteryx Hendrickx.

Reconstruction of Caudipteryx Hendrickx at the Sauriermuseum of Aathal, Switzerland.
Image credits Christophe Hendrickx.

Two-legged dinosaurs likely started dabbling in active flight while running, new research reveals. The findings provide new insight into how these reptiles evolved the ability to fly, a debate that’s been raging ever since 1861 and the discovery of Archaeopteryx. The results point to an alternative evolutionary path that didn’t rely on an intermediate gliding phase, suggesting that the two types of flight have different origins.

Dinos of a feather flap their wings together

“Our work shows that the motion of flapping feathered wings was developed passively and naturally as the dinosaur ran on the ground,” says lead author Jing-Shan Zhao of Tsinghua University, Beijing. “Although this flapping motion could not lift the dinosaur into the air at that time, the motion of flapping wings may have developed earlier than gliding.”

To the best of our knowledge, dinosaurs perfected gliding-type flight much earlier than active flight. The sensible assumption, then, would be that active flight developed from gliding — the two are very similar, mechanically. However, Zhao and his colleagues weren’t convinced. The team studied Caudipteryx, the most primitive non-flying dinosaur known to have had feathered “proto-wings.” It weighed around 5 kilograms, very little for a dinosaur, and looked like a miniature, feathered, beaked T-Rex.

The first part of the research revolved around understanding how Caudipteryx moved about. Using a mathematical approach called modal effective mass theory, the team looked at how the various parts of this dinosaur’s body fared during running, how they moved, and what mechanical forces they were subjected to. From these calculations, the team estimates that running speeds between about 2.5 to 5.8 meters per second would have created forced vibrations that caused the Caudipteryx’s wings to flap. So far, so good — previous research has estimated that Caudipteryx could reach running speeds of up to 8 meters per second, so it could easily achieve the speed interval calculated by the team.

Caudipteryx robot.

Caudipteryx robot used in the tests.
Image credits Talori et al., (2019), PLOS.

Then came the fun part: in order to check their results, the team constructed a life-sized robot Caudipteryx and made it run at different speeds. This step confirmed the initial findings — running motions in the 2.5 to 5.8 meter per second range caused a flapping motion of the wings. To double-double check the results, the team also fitted artificial wings on a young ostrich. Here too, running caused the wings to flap. Longer and larger wings providing a greater lift force, the team notes.

So the first part of this hypothesis seems to pan out. Zhao says that the next step is to analyze the lift and thrust of Caudipteryx’s feathered wings during the passive flapping process, to see if the animal could actually sustain flight over meaningful distances, or just tended to hop around.

The paper “Identification of avian flapping motion from non-volant winged dinosaurs based on modal effective mass analysis” has been published in the journal PLOS Computational Biology.

Running man.

One broken gene made us very good runners

A genetic fluke two to three million years ago turned humans into the best endurance runners around.

Running man.

Image via Pixabay.

A new paper published by researchers from the University of California San Diego School of Medicine reports that our ancestors’ functional loss of one gene called CMAH dramatically shifted our species’ evolutionary path. The loss altered significant metabolic processes, with impacts on fertility rates and risk of developing cancer.

The same change may have also made humans one of the best long-distance runners on Earth, the team adds.

These genes were made for runnin’

Our ancestors were presumably quite busy two to three million years ago transitioning from living in trees to live on the savannah. They were able to walk upright by this time, but they weren’t particularly good at it.

However, soon after this, some of our ancestors’ physiology starts undergoing some striking changes. Most relevant are shifts we see in their skeletons, resulting in long legs, big feet, and large gluteal muscles (butts) — all very good for walking around. These shifts were also accompanied by the evolution of sweat glands with much the same layout and capacity as ours which, according to the team, is quite expansive and much better at dissipating heat than that of other large mammals.

In other words, humanity received powerful legs and one of the most solid cooling systems in one fell swoop.

Our ancestors proceeded to use their new toys to hunt and eat anything they could bring down. They did so by adopting a hunting pattern unique among primates (and very rare among animals in general) known as persistence hunting: they would go out in the heat of the day, when other carnivores were resting, relying on their legs and sweat glands to chase prey until — exhausted and overheated — it couldn’t physically run away anymore.

We didn’t know much about the biological changes that underpinned this radical change, however. The first clues were uncovered around 20 years ago — when Ajit Varki, a physician-scientist at the University of California, San Diego (UCSD), and colleagues unearthed one of the first genetic differences between humans and chimps: a gene called CMP-Neu5Ac Hydroxylase (CMAH). Other species of primates also have this gene.

We, however, have a broken version of CMAH. Varki’s team calculated that this genetic change happened 2 million to 3 million years ago, based on the genetic differences among primates and other animals.

More recent research has shown that mice models with a muscular dystrophy-like syndrome exhibit more acute symptoms when this gene is inactivated. This hinted to Varki that the faulty gene might be what led to the changes our ancestors experienced in the savannahs.

“Since the mice were also more prone to muscle dystrophy, I had a hunch that there was a connection to the increased long distance running and endurance of Homo,” said Varki.

UCSD graduate student Jonathan Okerblom, the study’s first author, put the theory to the test. He built mouse running wheels, borrowed a mouse treadmill, and pitted mice with a normal and broken version of CMAH to the task.

“We evaluated the exercise capacity (of mice lacking the CMAH gene), and noted an increased performance during treadmill testing and after 15 days of voluntary wheel running,” Okerblom explained.

The two then consulted Ellen Breen, Ph.D., a research scientist in the division of physiology, part of the Department of Medicine in the UC San Diego School of Medicine. She examined the mice’s leg muscles before and after running different distances, some after 2 weeks and some after 1 month.

After training, mice with the human-like version of CMAH ran 12% faster and 20% longer than the other mice, the team reports. Breen adds that the mice displayed greater resistance to fatigue, increased mitochondrial respiration and hind-limb muscle, with more capillaries to increase blood and oxygen supply. Taken together, Varki says the data suggest CMAH loss contributed to improved skeletal muscle capacity for oxygen utilization.

“And if the findings translate to humans, they may have provided early hominids with a selective advantage in their move from trees to becoming permanent hunter-gatherers on the open range.”

The most likely cause of this change was evolutionary pressures associated with an ancient pathogen, the team explains.

The version of the gene we carry determines the loss of a sialic acid called N-glycolylneuraminic acid (Neu5Gc), and accumulation of its precursor, called N-acetylneuraminic acid or Neu5Ac, which differs by only a single oxygen atom. Sialic acids serve as vital contact points for cell-to-cell interaction and cellular interactions with the surrounding environment. This change likely led to enhanced innate immunity in early hominids, according to past research.

Sialic acids may also be a biomarker for cancer risk, and the team has also reported that certain sialic acids are associated with increased risk of type 2 diabetes; may contribute to elevated cancer risk associated with red meat consumption, and trigger inflammation.

“They are a double-edged sword,” said Varki. “The consequence of a single lost gene and a small molecular change that appears to have profoundly altered human biology and abilities going back to our origins.”

The paper “Human-like Cmah inactivation in mice increases running endurance and decreases muscle fatigability: implications for human evolution” has been published in the journal Proceedings of the Royal Society B.

Children shoes.

Scientists find the step-by-step process by which your shoelaces come undone

Researchers from the University of California Berkeley finally have the answer to why our shoelaces become untied when we walk – and what can do to make it happen less often.

Children shoes.

Shoelaces have a very annoying tendency to come undone out of the blue, for no apparent reason. To find out why, a team of researchers from the University of California took to the treadmill with a high-speed camera. They report that the repeated, specific impact generated by walking loosens the knot and then pulls it apart.

The team was led by Christine Gregg, a Berkeley mechanical engineering PhD student. Being a runner herself, Gregg laced up and ran on a treadmill so the team could study what happened to the knots. They filmed the shoes using a super-high-speed camera recording at about 900 frames per second, so they could take a frame-by-frame look at what was happening.

The recording showed that the impact of each step hitting the ground loosens the knot, and the swinging motion generated at the laces’ ends as our feet move forward pulls the knot apart. Furthermore, the team showed that both these elements have to work together to untie your laces – Gregg’s knots stayed firm when she sat on a chair and swung her legs back and forth or when she stomped down on the ground without any swinging motion. Finally, running makes the knots come undone much faster since it’s more energetic than walking.

The knot to tie all knots

But as we all probably well know, not all shoelaces come untied everytime you go for a walk or a jog. Obviously, tying them tighter makes it less likely they’ll do so. But there’s also another way you can tie them to make the know last longer, the team says – although currently, they don’t really know why this works, just that it does.

The usual (and weaker) bow is based on the ‘granny knot’, they write. You tie it up by crossing the left end over the right one and bringing the left end under and out. You make a loop in your right hand, wrap the other lace counter-clockwise around the loop, and finally pull it through. But they found that a bow based on the square knot fares much better when walking or running. You start tying it the same way as the knot above. The difference is that after you make a loop in your right hand, you instead wrap the other lace clockwise around it.

Tying shoelaces.

Image credits University of California, Berkeley.

Both of these knots will eventually come undone, the team says, but the weaker bow failed twice as often as the stronger one over a 15-minute running period.

On a more personal note, I’ve found that if you tie your shoelaces into a knot and then take the two loops of the bow and knot them again, you shouldn’t have any problem with them coming undone.

Still, while trials can show us which knots are strong and which are likely to fall apart pretty fast, we don’t really know why.
The research could help further our understanding of this question, and has implications for several fields of activity: for example, it could help design better stitches which are less likely to come undone.

The full paper “The roles of impact and inertia in the failure of a shoelace knot” has been published in the journal Proceedings of the Royal Society A.

Walking

Humans hacked walking by stepping on the heel not the toes, like other animals do

Why do humans step on their heels, while most animals do so on the balls of their feet? A longer leg is better suited to walking and running, so why would we evolve shorter ones? A new study found that stepping heel-to-toes makes for a longer “virtual leg”, allowing us to walk and run more efficiently.

Walking

Image via giphy

For mammals aiming to get better at walking, the best bet is to evolve longer legs. You can see it in how cats’ or dogs’ legs are shaped — the heel is high in the air and the foot touches the ground on the little balls behind the toes. But humans, who are walkers by excellence, have dropped this system altogether and evolved a heel-to-toe stepping style.

For University of Arizona anthropologist James Webber, this question was particularly intriguing — he took up barefoot running 12 years ago and has had plenty of time to ponder on how his feet hit the pavement. Shod runners typically land their steps with an initial heel strike, while barefoot runners tend to land on the middle part or the balls of the foot. This, however, would feel unnatural to them while walking.

So what gives?

In his latest study, Webber describes why humans have evolved this seemingly counter-intuitive stride.

“We’ve dropped our heels down on the ground, which physically makes our legs shorter than they could be if were up on our toes, and this was a conundrum to us (scientists),” Webber said.

So Webber and co-author UA anthropologist David Raichlen set up a treadmill in the University’s Evolutionary Biomechanics Lab and started looking at people walk. They asked some participants to walk normally and others to walk toe-first. The later group moved slower and put in 10% more effort than their counterparts.

The two believe that the answer still comes down to limb length. While animals usually elevate the heel to increase this value, Webber says heel-first walking creates a longer limb by adding some “virtual leg”. He describes a walking human as an inverted pendulum. Our bodies can be seen as pivoting over the point where the soles come in contact with the ground. As we step, our weight is distributed along the length of the sole and the true pivot point “forms” midfoot several centimeters below the ground, allowing for longer strides.

“Humans land on their heel and push off on their toes. You land at one point, and then you push off from another point eight to 10 inches away from where you started. If you connect those points to make a pivot point, it happens underneath the ground, basically, and you end up with a new kind of limb length that you can understand,” Webber explains.

“Mechanically, it’s like we have a much longer leg than you would expect.”

To take it another way, let’s simplify a step taken by an animal into three points forming a downward triangle. The lower point would be where the foot touches the ground, and the two points on top would be where the hips are at the start and the end of the stride. The longer the line connecting the step and hip points (the leg,) the longer the stride becomes. Webber found that while the step point is at ground level for other animals, it’s actually underground for humans. This makes the sides of the triangle longer than our legs actually are because we gain “extra leg” underground, so to speak.

A leg up

The team found who subjects that walked normally had legs that were, in essence, 15 centimeters (5.9 inches) longer. Even better, this virtual limb length means we’re more efficient walkers than if we landed on the balls of our feet.

“The extra ‘virtual limb’ length is longer than if we had just had them stand on their toes, so it seems humans have found a novel way of increasing our limb length and becoming more efficient walkers than just standing on our toes,” Webber said.

“It still all comes down to limb length, but there’s more to it than how far our hip is from the ground. Our feet play an important role, and that’s often something that’s been overlooked.”

When speeding up the treadmill to study the transition from walking to running, the team also found that toe-first participants switched to running at lower speeds — further suggesting that it’s less efficient for humans.

Archaeological evidence (footprints found preserved in volcanic ash in Latoli, Tanzania) shows that ancient hominids have been heel-to-toe walking for at least 3.6 million years now. But they likely had rigid feet, proportionately much longer than our own — about 70% the length of their femur, compared to our 54%. This likely made them better runners than modern humans, but Webber thinks we’ve evolved shorter legs to become better hunters and pursuers.

“When you’re running, if you have a really long foot and you need to push off really hard way out at the end of your foot, that adds a lot of torque and bending.”

“So the idea is that as we shifted into running activities, our feet started to shrink because it maybe it wasn’t as important to be super-fast walkers. Maybe it became important to be really good runners,” Webber concludes.

Well, now at least I know why my girlfriend walks so slow in heels — she’s losing more virtual leg than gaining actual leg. Not that I’m complaining.

I’m all about actual legs.

The full paper “The role of plantigrady and heel-strike in the mechanics and energetics of human walking with implications for the evolution of the human foot” has been published in The Journal of Experimental Biology.

jogging running

Jogging can add years to your life – here are six simple tips to get you started

jogging running

Credit: Pixabay

The sight of the determined, lycra-clad jogger has become a familiar feature of urban parks around the world. Jogging – defined as “the activity of running at a steady, gentle pace” – was made popular by running pioneer Arthur Lydiard, who realised that this was a better way to train for competition than sprinting to exhaustion. Jogging gained a huge following in the 1980s, and has recently experienced something of a resurgence.

There are clear health benefits to this relatively cheap and accessible activity. The Copenhagen City Heart study – which collected data between 1976 and 2003 – revealed that regular jogging increases the life expectancy of men by 6.2 years, and women by 5.6 years.

Peter Schnohr, chief cardiologist of the study, found that jogging improves oxygen intake and heart function, reduces blood pressure and inflammation markers, increases insulin sensitivity and bone density, and helps to prevent obesity and blood clots, among many other things.

So, how much jogging do you have to do to gain this bounty of benefits? The Copenhagen City Heart study itself recommends between 60 and 150 minutes per week, in total. The UK’s National Health Service (NHS) likewise suggests that 19- to 64-year-olds should be doing 150 minutes of moderate aerobic exercise each week – where aerobic exercise is a workout which you can maintain for relatively long periods, without too much impact on your breathing rate.

These benefits are maximised by jogging for more than 20 minutes, at least three to five times per week. But, based on my own experience as a competitive runner and coach, there are a few other tricks you can use to get the most out of your regular jog.

1. Improve your technique

Everybody runs differently, so your technique is going to be unique. Even so, there are a few key pointers that may help. The UK Athletics resource UCoach recommends running tall, with high hips, and placing each foot directly beneath your centre of mass keeping your arm action relaxed and efficient, with rhythmical stride. Within the first ten weeks, new joggers should expect to see their movement become more efficient, and their running gait improve.

2. Wear the right shoes

Going to a specialist running store is very useful – they should be able to give you feedback and advice on your current running shoes, your technique and what extra support you require. This can make a big difference when it comes to preventing injuries; something all runners are trying to achieve.

Keep in mind, however, that the most expensive shoes might not be the best – in fact, it’s probably more important to make sure they are comfortable.

3. Set goals

Setting goals is proven to give you the motivation you need to get started, and to continue training. These may include personal goals to get fit and lose weight, or you may aim to complete an event like a 5km, 10km or half or full marathon. Remember, any goal is a great tool – but you may simply enjoy jogging – that’s fine, too.

4. Mix it up

Mixing up your jogging routes and venues is key to beating off potential boredom. So, make sure not all your jogs are over the same distance and on the same loop. You can’t beat a new trail for a longer jog, just make sure you know where you are going – or you may be running for longer than you anticipated.

5. Become a social jogger

Jogging with others is a great way to be social and also go longer and further. The rise of the Parkrun is a global phenomenon that gets many thousands of people each week running, jogging and walking over a 5km distance. There are many Parkruns spread all over the UK. It is free to enter, and they happen every Saturday morning at 9am in many urban parks.

6. Smarten up your jog

This is jogging for the new age. There are numerous smartphone apps and trackers that will monitor and motivate you. They will measure your routes, give you split times and show your progression. You can do virtual jogs with your friends, have mini competitions and even have real-time online coaching support from trained professionals.

There are even apps that will create a music playlist with beats to match your steps per minute. Research tells us that synchronised music increases exercise output, and helps to reduce the perceived effort of jogging.

Jogging is an accessible urban sport – it’s also smart, sociable and healthy. It isn’t a surprise that jogging has made a comeback. So, put on your trainers, grab your smartphone, go for a jog and live longer.

James Thie, Performance Director of Athletics & Lecturer, Cardiff Metropolitan University

This article was originally published on The Conversation. Read the original article.

This is Tomatan, and he will power you through a marathon — with tomatoes

Ever felt like there was something missing while you go for a jog? Like an unsatisfied yearning, a hungering left unanswered?

If you did, you’re not alone. Japanese vegetable juice company Kagome thinks they have the answer in the shape of a wearable robot that feeds you tomatoes while you run. Weighing in at 18 pounds / 8kg, Tomatan can be worn as a tomato-headed-backpack.

At the flip of a switch Tomatan will grab a tomato with its metal arms then swing them over your head and feed the juicy treat to you. Japan-based artistic studios Maywa Denki, well known for their unusual musical instruments and other devices, designed the robot — and an inexplicably large amount of the berries were involved in the process.

“We used about 100 tomatoes to complete this machine,” said Novmichi Tosa, one of the founders of Meiwa Denki. “We focused mostly on its visual design.”

Now, I really like Tomatan. It looks awesome and seems like a great conversation starter with the mademoiselles. But there is one thing that’s still beyond my grasp…Why? Why would anyone want to bite into a tomato while he’s running?

Awesome? Undoubtedly. Useful? Well, according to Kagome, which claims to be Japan’s largest supplier of ketchup and tomato juice, people taking part in the Tokyo marathon really need this.

“Tomatoes have lots of nutrition that combats fatigue,” said Kagome employee Shigenori Suzuki.

Suzuki intends to wear Tomatan on Saturday 21st, when he will be representing Kagome in the Tokyo Marathon. During the 5km long fun run, Tosa will be running beside him with tools just in case the robot needs fixing or Suzuki encounters a problem.

Then on Sunday 22 February during the full Tokyo Marathon, a professional runner from Kagome will take part using a lighter version of the tomato robot known as Petit-Tomatan.

Petit-Tomatan weighs just 3kg and features a mini tomato holster that is worn on the back.
Image via klepa.ru

As this robot is much smaller, the runner will need to hold a delivery tube up to their mouth through which the tomatoes will be delivered. Petit-Tomatan also features a timer so the runner isn’t fed too many tomatoes in one go.