The Science of Walking and Running

English photographer Eadweard Muybridge (1830-1904), who pioneered the use of multiple cameras to capture motion, is shown walking heel-first as humans usually do. A new University of Utah study shows that stepping onto the heel first requires much less energy than putting the ball of the foot or the toes onto the ground first.

125 years after they were taken, Muybridge’s photographs are still of value in demonstrating scientific facts. New research at the University of Utah concerning walking uses a Muybridge self-portrait sequence to illustrate the positioning of the foot in walking.

“Our heel touches the ground at the start of each step. In most mammals, the heel remains elevated during walking and running,” says biology Professor David Carrier, senior author of the new study being published online Friday, Feb. 12 and in the March 1 print issue of The Journal of Experimental Biology.

“Most mammals – dogs, cats, raccoons – walk and run around on the balls of their feet. Ungulates like horses and deer run and walk on their tiptoes,” he adds. “Few species land on their heel: bears and humans and other great apes – chimps, gorillas, orangutans.”

“Our study shows that the heel-down posture increases the economy of walking but not the economy of running,” says Carrier. “You consume more energy when you walk on the balls of your feet or your toes than when you walk heels first.”

Heel First More Efficient For Walking is here:

http://www.redorbit.com/news/health/1822653/heel_first_more_efficient_for_walking/

and The Cost of Being on your Toes is here:

http://www.unews.utah.edu/p/?r=012710-3

An earlier University of Utah study of running appeared in Nature:

http://www.biology.utah.edu/bionews2.php?story=bramble111704.txt

Credit: Courtesy of Nature, cover by Justin Libby, Mathieu Baissac and Daniel Lieberman, after photographer Eadweard Muybridge’s 19th century studies of human motion.

The study, by University of Utah biologist Dennis Bramble and Harvard University anthropologist Daniel Lieberman,  appeared in the Nov. 18 2004 issue. It assembled evidence that humans evolved and human anatomy looks the way it does because our ancestors were more likely to survive if they could run.

The article prompted a Nature cover picture based on Muybridge sequence photos.

The gait of Elephants, on the other hand, is not so easily determined by photography (though Muybridge tried). Recent research using pressure plates suggests that when getting up speed elephants run with their front legs, and walk with their back legs – previous studies suggested the opposite. Do speedy elephants walk or run? is here:

http://newsvote.bbc.co.uk/mpapps/pagetools/print/news.bbc.co.uk/2/hi/science/nature/8508796.stm?ad=1