Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Human use heel first gait because it is efficient for walking

12.02.2010
Most running mammals totter along on their toes. In fact, toe running is far more efficient than landing heel first like humans. Yet when it comes to long distance endurance running, humans are some of the best-adapted animals for clocking up the miles, all be it inefficiently.

So, why have we stuck with our inefficient heel first footfall pattern when the rest of our bodies are honed for marathon running? This paradox puzzled Nadja Schilling and Christoph Anders from the Jena University, Germany, and Christopher Cunningham and David Carrier from the University of Utah, USA, until they began to wonder whether our distinctive heel first gait, inherited from our ape forefathers, might be an advantage when we walk.

The team put young healthy volunteers through their paces to find out why we walk and run heel first and publish their results on 12 February 2010 in The Journal of Experimental Biology at http://jeb.biologists.org.

Measuring the amount of oxygen consumed as their human subjects walked, the team asked the volunteers to walk in one of three different ways: normally, with the heel contacting the ground first; toes first, with the heel slightly raised so that it didn't contact the ground; and up on tip-toes. Then the scientists asked the athletes to repeat the experiments while running heel first and with their heels slightly raised. Calculating the amount of energy required to run and walk, the team found that walking with the heel slightly raised costs 53% more energy than walking heel first, and walking on tip-toe was even less economical. However, there was no difference between the runners' efficiencies when they ran with flat feet and up on their toes.

Our 'heel first' gait makes us incredibly efficient walkers, while both postures are equally efficient for runners. Human walkers burn roughly 70% less energy than human runners when covering the same distance. However, this efficiency would be completely wiped out if we switched to walking on our toes. 'Our ability to walk economically may largely be the result of our plantigrade [heel first] posture,' says Carrier.

But why is heel walking so much more efficient than walking on our toes? To find out, Carrier and his colleagues asked volunteers to run and walk at various speeds in the three postures while recording electrical activity in their muscles to see if the heel first walkers were saving energy by using their muscles differently from toe first walkers. The team also measured the volunteers' metabolic cost of standing on their toes, to find out if increasing stability saved energy, and the forces exerted by the ground on the volunteers' bodies, in case they were reduced in any way that could result in an energy saving.

Analysing the results, the team realised that we lose less energy as our heels collide with the ground than we do when we walk toes first. Landing heel first also allows us to transfer more energy from one step to the next to improve our efficiency, while placing the foot flat on the ground reduces the forces around the ankle (generated by the ground pushing against us), which our muscles have to counteract, resulting in another energy saving.

So we still use our ancestor's heel first gait because it makes us better walkers and Carrier adds, 'Given the great distances hunter-gatherers travel, it is not surprising that humans are economical walkers'.

IF REPORTING ON THIS STORY, PLEASE MENTION THE JOURNAL OF EXPERIMENTAL BIOLOGY AS THE SOURCE AND, IF REPORTING ONLINE, PLEASE CARRY A LINK TO: http://jeb.biologists.org

REFERENCE: Cunningham, C. B., Schilling, N., Anders, C. and Carrier, D. R. (2010). The influence of foot posture on the cost of transport in humans. J. Exp. Biol. 213, 790-797.

This article is posted on this site to give advance access to other authorised media who may wish to report on this story. Full attribution is required, and if reporting online a link to jeb.biologists.com is also required. The story posted here is COPYRIGHTED. Therefore advance permission is required before any and every reproduction of each article in full. PLEASE CONTACT permissions@biologists.com

Kathryn Knight | EurekAlert!
Further information:
http://www.biologists.com
http://jeb.biologists.org

More articles from Life Sciences:

nachricht New photocatalyst speeds up the conversion of carbon dioxide into chemical resources
29.05.2017 | DGIST (Daegu Gyeongbuk Institute of Science and Technology)

nachricht Copper hydroxide nanoparticles provide protection against toxic oxygen radicals in cigarette smoke
29.05.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

New photocatalyst speeds up the conversion of carbon dioxide into chemical resources

29.05.2017 | Life Sciences

NASA's SDO sees partial eclipse in space

29.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>