Muscle loss in old age linked to fewer nerve signals

 13 Mar 2018 - 15:07

Muscle loss in old age linked to fewer nerve signals

QNA

London: Researchers from Manchester Metropolitan University say they may have worked out why there is a natural loss of muscle in the legs as people age - and that it is due to a loss of nerves.

In tests on 168 men, they found that nerves controlling the legs decreased by around 30% by the age of 75.

This made muscles waste away, but in older fitter athletes there was a better chance of them being 'rescued' by nerves re-connecting, the study found.

Prof Jamie McPhee, from Manchester Metropolitan University, said young adults usually had 60-70,000 nerves controlling movement in the legs from the lumbar spine."There was a dramatic loss of nerves controlling the muscles - a 30-60% loss - which means they waste away," he said.

"The muscles need to receive a proper signal from the nervous system to tell them to contract, so we can move around." he added.

Researchers looked at muscle tissue in detail using magnetic resonance imaging (MRI) and they recorded the electrical activity passing through the muscle to estimate the numbers and the size of surviving nerves.

The good news is that healthy muscles have a form of protection: surviving nerves can send out new branches to rescue muscles and stop them wasting away.