Loss of muscle strength in the legs is a natural part of getting older, and one reason why an Acorn Stairlift can become an indispensable home help, enabling people to stay living independently in their own homes for longer.
Now scientists writing in the Journal of Physiology believe they have pinpointed the reason behind this natural loss of leg muscle as people age. After carrying out tests on 168 men, they found that nerves controlling the legs decreased by an average of 30% by the age of 75, and it is this loss of nerves which reduces leg strength.
It was the nerve loss which made the muscles waste away and although it is a natural part of ageing which eventually happens to everyone, it can be delayed by keeping fit for as long as possible. The research found that in fitter older people there was a better chance of wasting muscles being ‘rescued’ by nerves re-connecting, which is prompted by regular exercise.
Professor Jamie McPhee, from Manchester Metropolitan University, found that young adults usually had 60-70,000 nerves controlling movement in their legs from the lumbar spine, but this changed significantly in old age.
“There was a dramatic loss of nerves controlling the muscles – a 30 to 60% loss – which means they waste away,” said Prof. McPhee. “The muscles need to receive a proper signal from the nervous system to tell them to contract, so we can move around.”
In short, if a depleted network of nerves cannot properly carry the messages telling the muscles what to do, the uninstructed muscles become idle and start to waste away. The Manchester-based research team looked at muscle tissue in great detail using MRI scanning and recorded the electrical activity passing through the muscle to estimate the number and size of surviving nerves.
Where they found lots of electrical activity – evidence of nerves carrying messages to muscles – the leg muscles remained in good condition and strong. But where there was little electrical activity – evidence of significant nerve loss – the muscles were in poor condition and much weaker.
The better news was that healthy muscles seem to ensure their own survival for longer. The nerves supplying those muscles can send out new branches to stop muscles wasting away and ‘rescue’ them. The researchers found this is far more likely to happen in fit people with large, healthy muscles. In other words, people who exercise regularly are maintaining their leg muscle strength by also minimising their nerve loss.
Scientists are now working to understand why the connections between nerves and muscles begin to break down with age. Finding out more could help them delay or even reverse the process, meaning that people could remain stronger and more independent well into old age. As we are now living longer than ever before, this would bring obvious benefits for an ageing population.
Perhaps the activity which most acutely highlights loss of muscle strength in the legs is going up and down stairs. As we get older, the stairs in our homes can become a real challenge. Where once we bounded up and down without a thought, we now have to work hard, going carefully and slowly.
Carrying on using the stairs can help to maintain our muscle strength, as outlined above, but there comes a point when the benefit is outweighed by the discomfort and, more importantly, the danger. If you no longer have confidence that your legs are strong enough to get you safely up and down the stairs, it is time to invest in an Acorn Stairlift. If there is one place in your home where you don’t want your strength to let you down, it is on the stairs. Far better to exercise in a safe and controlled environment, using exercises which specifically target the muscle groups you want to work on, than to take a chance on the stairs.
The lifestyle section of the new Acorn Stairlifts brochure has the second in a series of articles by fitness guru Mr Motivator, who remains remarkably healthy at 65. His articles focus on exercises which people can do whatever their level of mobility. For your free copy of the brochure, call us today on 0800 016 9760.