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It’s good to keep on your toes. Metaphorically, that is. Not when you’re actually out for a stroll. Because a new study suggests that it takes nearly twice as much energy to walk on your toes than it does to land on your heel.
Humans are among a small handful of animals that tend to strut heel-to-toe. Chimps and other apes do it, as do bears. But most critters bounce on the balls of their feet—think cats and dogs—while others trot on their toes, like horses and deer.
To find out whether our gait gives us any advantages, scientists asked 27 volunteers to walk on a treadmill all three ways: heel-first, ball-of-the-foot first, or up on tippy toes. The participants also wore face masks that enabled the researchers to measure their oxygen consumption. The results: the subjects walking on the balls of their feet, in addition to looking ridiculous, expended 50 percent more energy. The ones prancing on their toes needed 83 percent more energy. The study is in the Journal of Experimental Biology.
The bottom line: landing on our heels provides more leverage and limits energy losses to the ground. And does not look like a tribute to classic Monty Python.
—Karen Hopkin
[The above text is an exact transcript of this podcast.]
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7 Comments
Add CommentA treadmill shows participants to be traveling uphill. Try the same study as free moving subjects with little resistance to motion while walking on a level plain. Perhaps that wil change the odds???
Reply | Report Abuse | Link to thisI hope this is not a response to the mid-foot strike gaining popularity along with barefoot running. A heel strike when running is proving to be a jolt to the body. In terms of walking mechanics, it would hardly require a study to prove that a heel landing is more efficient.
Reply | Report Abuse | Link to thisSeriously. This is not a valid study.
Reply | Report Abuse | Link to thisIf the normal gait of a human is heel to toe, asking a human to use a different gait would naturally expend more energy. A human unused to a gait of walking on the ball of their foot would naturally have to use an additional amount of energy finding balance and staying balanced - ie compensating for vast number to times they lose balance and so on. Also the stress of the natural gait and the fear of falling would contribute. Finally the eventual pain from using a new set of muscles and repeated stress on the ball (or toes) of your foot.
This doesn't prove anything except humans are designed to walk heel to toes, which was already obvious.
On the other hand, the research could have had an entirely different purpose in mind and the reporter has misled us which has of course happened before.
SciAm editors; for future reference, please provide the name of the investigator in these transcripts, so that if readers are so inclined they can look up the "study" referenced. In light of the recent Nature article pointing out that "running" barefoot results in a different gait, in which the ball of the foot strikes first rather than the heelstrike that occurs when running with shoes, and that this type of running seems to result in few injuries......I am curious about the source of funding for this study.
Reply | Report Abuse | Link to thisLink to the article anyone?
Reply | Report Abuse | Link to thisThis article was apparently based on Kathryn Knight's review "Humans' Heel First Gait is Efficient for Walking" of the journal article "The influence of foot posture on the cost of transport in humans".
Reply | Report Abuse | Link to thisThere is *no excuse* for failing to provide the name of the principal investigator when describing a study. When the popular media says "scientists say", all too often, the unnamed scientists in question said nothing of the sort.
@user001
This study looked at oxygen usage and found that we get better *walking* efficiency with a plantigrade stance than digitigrade. They found it didn't help the subjects *run* more efficiently. The authors also suggest that it may be responsible for humans' unusually high difference in efficiency between running and walking- running is 72% harder.
This study also showed a very high variability between subjects; walking on the balls of the feet took on average 53% more oxygen than normal walking, but the measurement came with a 20% standard deviation. That is, you can trust (with p=.001) their conclusion that heel is better for walking, but don't expect that average to be representative of any given person.
As for the suggestion that a shoe company would dislike the finding that barefoot running results in less foot pressure, think again. Nike also makes a minimal shoe for barefoot-style running. They win no matter what the science says. Funding for this study was was by the NSF, Friedrich Schiller University Jena, and the BGN: praevention.portal.bgn.de
I can't speak for the other animals, but a horse that trots (a jog, for the non horse folks) on their toe is moving incorrectly. That is considered a gait abnormality, normally caused by a lameness or a poor shoeing job. Extremely stressful for the lower limb to move like this. When I see gross factual errors like this it really makes me wonder if anyone is bothering to do any basic research.
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