PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

A formula that can calculate a person's speed by just looking at their footprints

2013-04-22
(Press-News.org) Two Spanish scientists have designed an equation that provides a highly accurate estimate of an individual's speed based on stride length. They used data from professional athletes and walking and running experiments on a beach in order to come up with the equation. The result has applications in the study of fossil trackways of human footprints.

In the spring of 2008, 14 palaeontology students from the Complutense University of Madrid ran along a beach in Asturias (Spain) at the request of a planetary geologist who was a friend of their fieldwork director. Javier Ruiz, from the Complutense University of Madrid (Spain), and his colleague Angélica Torices, from the University of Alberta (Canada), just out of curiosity, wanted to check how accurately an individual's speed could be calculated based on their tracks.

The results, published in 2013 in the journal 'Ichnos', show that, without needing any other data such as leg length, they were able to achieve quite a high degree of accuracy, with a margin of error of 10 to 15%.

"For humans, we are able to calculate speed based on stride length alone with a very good degree of accuracy," Javier Ruiz told SINC.

The authors applied their formula to estimate the speed at which the humans were travelling who left the Pleistocene era fossil trackways found in the Willandra Lakes Region of Australia.

"A previous study had made a very elaborate calculation of their speed but the results were as high as if they had been professional athletes" Ruiz explained. His results show a reasonable sprint pace.

In order to come up with their equation, Ruiz and Torices compared the data obtained in the experiments with the students with data from professional athletes who compete in 100 and 400-metre races.

Up to now, the individual's leg length or at least an estimate of the length was required to calculate speed based on tracks. An equation formulated by the British zoologist Robert McNeil Alexander in 1976 was used which he based solely on data obtained from his children running.

Ruiz and Torices measured the speed and stride length of the students as they ran along the beach and applied Alexander's equation. "The data fit with the equation very well", Ruiz explained, "Alexander did a good job with very little statistical data but with a large mathematical basis and we have seen empirically that his equation is correct."

The speed of elite athletes

In the case of the athletes, the researchers had data on speed and stride length but not limb length, which led Ruiz to modify the equation so that this piece of data was not needed. "There was a very good degree of accuracy with the new equation with a 15% margin of error, even better than the equation that was generally used whose margin of error was 50%."

In addition, the calculation works perfectly well both whether the individuals are running or walking and this was very surprising according to Ruiz. "There is a little more variability in running but even so it works very well."

Despite that fact that the speed calculation is very accurate, Ruiz admits that it cannot be applied in an absolute and unequivocal manner but rather statistically. "Strangely, sometimes 400 and 100-metre athletes have the same stride length but run at different speeds. What the body does is try to optimise how energy is used at a given speed."



INFORMATION:

Reference:

J. Ruiz y A. Torices. "

Contact:

Javier Ruíz
Departmento de Geodinámica - Facultad de Geología
Universidad Complutense de Madrid
Email: jaruiz@geo.ucm.es
Tel: +34 913944821 "

Ichnos DOI: 10.1080/10420940.2012.759115



ELSE PRESS RELEASES FROM THIS DATE:

Metastasis stem cells in the blood of breast cancer patients discovered

2013-04-22
Individual cancer cells that break away from the original tumor and circulate through the blood stream are considered responsible for the development of metastases. These dreaded secondary tumors are the main cause of cancer-related deaths. Circulating tumor cells (CTCs) detectable in a patient's blood are associated with a poorer prognosis. However, up until now, experimental evidence was lacking as to whether the "stem cell" of metastasis is found among CTCs. "We were convinced that only very few of the various circulating tumor cells are capable of forming a secondary ...

In India hip fracture is associated with high rates of mortality and disability

2013-04-22
In various studies across different countries the reported one year mortality risks after hip fracture can vary anywhere from 5 to 50 %. In India, however, there has been little research on the risk of mortality and functional impairment following hip fracture. In an oral presentation held during the European Congress on Osteoporosis & Osteoarthritis in Rome, Italy, held from April 17 to 20 in Rome, Italy, researchers from Maulana Azad Medical College, New Delhi, India presented findings from a prospective study which found that patients had a high rate of one-year mortality ...

Is food truly addictive?

2013-04-22
Philadelphia, PA, April 22, 2013 – Biological Psychiatry is proud to announce this week's publication of a special issue focusing on the question of food as an addiction. Addiction is the continued or compulsive use of a substance, despite negative and/or harmful consequences. Over the years, addiction has come to be re-defined to include behaviors, as well as substances, and the term is now used to describe significant problems with alcohol, nicotine, drugs, gambling, internet use, and sex. The 'major' addictions, like alcoholism and drug abuse, stimulate significant ...

Surgical delay of more than 48 hours increases mortality in older hip fracture patients

2013-04-22
Although hip fractures in older patients are known to be a major cause of long term disability and increased risk of death, less is known about the relationship between surgical delay after hip fracture and mortality risk. A study by Belgian investigators shows that that in older patients with hip fracture, surgical delay of more than 48 hours is significantly and independently associated with increased long-term mortality, even after adjusting for age, sex, and co-morbidities. The study analysed data from 32,383 participants with 1 years of follow-up, extracted from ...

Study shows reproductive effects of pesticide exposure span generations

2013-04-22
North Carolina State University researchers studying aquatic organisms called Daphnia have found that exposure to a chemical pesticide has impacts that span multiple generations – causing the so-called "water fleas" to produce more male offspring, and causing reproductive problems in female offspring. "This work supports the hypothesis that exposure to some environmental chemicals during sensitive periods of development can cause significant health problems for those organisms later in life – and affect their offspring and, possibly, their offspring's offspring," says ...

New review sets international standards for best practice in fracture liaison services

2013-04-22
Fragility fractures due to osteoporosis are a major cause of disability or premature death in older adults. Those at highest risk are patients who have already suffered one fragility fracture; they are at twice the risk of suffering a future fracture compared to others who have not fractured. Nevertheless health care systems around the world are failing to identify and treat these patients, leaving them exposed to debilitating and life-threatening secondary fractures. Based on evidence from numerous global studies, a new report, 'Capture the Fracture: A Best Practice ...

Forensic sciences are 'fraught with error'

2013-04-22
Amsterdam, April 22, 2013 – A target article recently published in Journal of Applied Research in Memory and Cognition (JARMAC) reviews various high-profile false convictions. It provides an overview of classic psychological research on expectancy and observer effects and indicates in which ways forensic science examiners may be influenced by information such as confessions, eyewitness identification, and graphical evidence. The target article authors, Saul Kassin and Jeff Kukucka, of John Jay College of Criminal Justice, and Itiel Dror, University College, London, point ...

Grape intake may protect against metabolic syndrome-related organ damage

2013-04-22
ANN ARBOR, MI - Consuming grapes may help protect against organ damage associated with the progression of metabolic syndrome, according to research presented Monday at the Experimental Biology conference in Boston. Natural components found in grapes, known as polyphenols, are thought to be responsible for these beneficial effects. The study, led by investigator E. Mitchell Seymour, Ph.D., of the University of Michigan Health System, studied the effects of a high fat, American-style diet both with added grapes and without grapes (the control diet) on the heart, liver, ...

Honor among (credit card) thieves?

2013-04-22
EAST LANSING, Mich. — A Michigan State University criminologist dug into the seamy underbelly of online credit card theft and uncovered a surprisingly sophisticated network of crooks that is unique in the cybercrime domain. The thieves, Thomas Holt found, run an online marketplace for stolen credit data similar to eBay or Amazon where reputations drive sales. Thieves sell data and money laundering services, advertised via web forums, and send and receive payments electronically or through an intermediary. They even provide feedback on transactions to help weed out sellers ...

Researchers discover mushrooms can provide as much vitamin D as supplements

2013-04-22
(Boston)—Researchers from Boston University School of Medicine (BUSM) have discovered that eating mushrooms containing Vitamin D2 can be as effective at increasing and maintaining vitamin D levels (25–hydroxyvitamin D) as taking supplemental vitamin D2 or vitamin D3. These findings will be presented at the American Society for Biochemistry and Microbiology annual meeting in Boston on April 22 and also concurrently appear in Dermato-Endocrinology on line open access. Vitamin D is crucial for good bone health and muscle strength; adequate amounts help the body maintain ...

LAST 30 PRESS RELEASES:

The Lancet Diabetes & Endocrinology: Higher doses of semaglutide can safely enhance weight loss and improve health for adults living with obesity, two new clinical trials confirm

Trauma focused therapy shows promise for children struggling with PTSD

School meals could drive economic growth and food system transformation

Home training for cerebellar ataxias

Dry eyes affect over half the general population, yet only a fifth receive diagnosis and treatment

Researchers sound warning about women with type 2 diabetes taking oral HRT

Overweight and obesity don’t always increase the risk of an early death, Danish study finds

Cannabis use associated with a quadrupling of risk of developing type 2 diabetes, finds study of over 4 million adults

Gestational diabetes linked to cognitive decline in mothers and increased risk of developmental delays, ADHD and autism among children

Could we use eye drops instead of reading glasses as we age?

Patients who had cataracts removed or their eyesight corrected with a new type of lens have good vision over all distances without spectacles

AI can spot which patients need treatment to prevent vision loss in young adults

Half of people stop taking popular weight-loss drug within a year, national study finds

Links between diabetes and depression are similar across Europe, study of over-50s in 18 countries finds

Smoking increases the risk of type 2 diabetes, regardless of its characteristics

Scientists trace origins of now extinct plant population from volcanically active Nishinoshima

AI algorithm based on routine mammogram + age can predict women’s major cardiovascular disease risk

New hurdle seen to prostate screening: primary-care docs

MSU researchers explore how virtual sports aid mental health

Working together, cells extend their senses

Cheese fungi help unlock secrets of evolution

Researchers find brain region that fuels compulsive drinking

Mental health effects of exposure to firearm violence persist long after direct exposure

Research identifies immune response that controls Oropouche infection and prevents neurological damage

University of Cincinnati, Kent State University awarded $3M by NSF to share research resources

Ancient DNA reveals deeply complex Mastodon family and repeated migrations driven by climate change

Measuring the quantum W state

Researchers find a way to use antibodies to direct T cells to kill Cytomegalovirus-infected cells

Engineers create mini microscope for real-time brain imaging

Funding for training and research in biological complexity

[Press-News.org] A formula that can calculate a person's speed by just looking at their footprints