Study of leaping toads reveals muscle-protecting mechanism (w/ video)

Dec 19, 2012

(Phys.org)—Most people are impressed by how a toad jumps. UC Irvine biologist Emanuel Azizi is more impressed by how one lands.

An assistant professor of ecology & evolutionary biology who specializes in muscle physiology and biomechanics, Azizi found that nature's favorite leapers possess a neuromuscular response that's specific to the intensity of a landing – a mechanism that protects muscles from injury upon impact.

The research is helping reveal how the nervous system modulates motor control patterns involved with jumping and landing. Azizi's findings on the underlying function of control, he said, could one day improve rehabilitation programs for people with neuromuscular deficiencies.

This video is not supported by your browser at this time.
Video of leaping toad.

In all vertebrates – from to humans – muscles contract to provide jumping power. Landing, however, requires that muscles stretch to dissipate energy and slow the body. But if muscles become overstretched during landing, injury can occur.

For a study appearing online today in Biology Letters, Azizi and UC Irvine graduate student Emily Abbott measured toads' muscular responses to leaps of different lengths. They discovered that during landing, toads' muscles adapt to the varying intensity of impact. As the creatures hop over longer distances, their landing muscles increasingly shorten in anticipation of larger impacts.

This pattern indicates that rapid and coordinated responses of the nervous system can act to protect muscles from injury, said Azizi, who added that future efforts will be aimed at understanding what sensory information is used to modulate these responses.

"Toads are ideal for studying jumping and landing because they're so good at it," he noted. "This work is providing the basic science on how muscles respond during high-impact behaviors like or falling."

Explore further: Aging white lion euthanized at Ohio zoo

add to favorites email to friend print save as pdf

Related Stories

Tendons absorb shocks muscles won't handle

Sep 27, 2011

Anyone who has hiked down a mountain knows the soreness that comes a day or two after means the leg muscles have endured a serious workout. While the pain is real, it's not well understood how leg muscles ...

Frogs' amazing leaps due to springy tendons

Nov 16, 2011

Some species of frogs and many other animals are able to jump far beyond what appear to be their capabilities. The trained contestants in the frog-jumping competition in Calaveras County, Calif., come to mind, ...

Toad research could leapfrog to new muscle model

Jun 02, 2008

A toad sits at a pond's edge eyeing a cricket on a blade of grass. In the blink of an eye, the toad snares the insect with its tongue. This deceptively simple, remarkably fast feeding action offers a new look ...

Targeting leg fatigue in heart failure

Oct 31, 2011

Doctors should not only treat the heart muscle in chronic heart failure patients, but also their leg muscles through exercise, say researchers in a study published today in the Journal of Applied Physiology.

Recommended for you

A vegetarian carnivorous plant

Dec 19, 2014

Carnivorous plants catch and digest tiny animals in order and derive benefits for their nutrition. Interestingly the trend towards vegetarianism seems to overcome carnivorous plants as well. The aquatic carnivorous bladderwort, ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.