---

---

---

---

Science Current Events and Science News RSS Feeds

---

---

Email a Friend Printer Friendly

Using a catapult for rapid limb protraction

January 06, 2003

Alan Wilson, Johanna Watson and Glen Lichtwark have had their paper published by Nature.

This paper shows that fast runners must be able to protract their limbs quickly in order to prepare for the next stance phase, which is particularly challenging for large animals as their limbs are long and their muscles contract slowly and have a low power output.

The researchers show that horses cannot achieve the high power output required for rapid limb protraction by simple muscle contraction and that they deploy an elastic biceps muscle to store and then release energy. The muscle's catapult action has an output that is comparable to over 100 times its mass of non-elastic muscle. Although grasshoppers and fleas are known to rely on a similar catapult mechanism for rapid acceleration, this has not been demonstrated before in larger animals (to the knowledge of the researchers). It is likely that similar mechanisms exist in other animals.

Dr Alan Wilson works in the Structure and Motion Laboratory, Department of Veterinary Basic Sciences, the Royal Veterinary College, Glen Litchwark is based at the Institute of Human performance at University College London, Stanmore, Middlesex.

For a copy of the paper, please contact Virginia Fisher at vfisher@rvc.ac.uk

Royal Veterinary College, The