If you’ve ever wondered why many older people walk so slowly, research now has the answers.
A study recently published in The Journal of Physiology has found that elderly people walk at a slower speed and tire more quickly because of loss of strength and mass in leg muscles. Using computer simulations researchers found that these physiological changes explain the slower walking speed, and that a focus on building up these leg muscles may be the only effective way to improve elderly walking.
Walking performance, measured in terms of energy efficiency – i.e. how far one can travel per calorie consumption – and walking speed, has been shown to decline as people get older. The reason for this decline is unknown as ageing produces a range of physiological changes which affect gait (a person’s manner of walking), but are hard to study individually.
This decline in walking performance can lead to a less active lifestyle worsening the health of elderly people and is directly linked to a lower 10-year survival rate for people at age 75. The findings of this study suggest that a focus on building up muscles in the legs may be the only effective way to improve elderly walking. In other words, improving other features such as joint flexibility or walking strategy would not help normal elderly people to walk better.
Physiotherapist Neil Barback, owner and lead physio at Te Puke Physiotherapy, agrees that building and maintaining strength is important for older people, as they tend to lose muscle mass very quickly in their later years.
He recommends a programme involving body weight exercises. Activities such as squats, sits-to-stands, lunges and calf raises are all good starting points and a person can progress to adding light dumbbells if appropriate, he says.
Repetitions of exercises are a good way of building endurance. A typical repetition set would be three lots of 12 of each exercise, although Barback stresses that an exercise programme should be tailored to a person’s individual needs, strength and fitness levels.
He says consistency is crucial, and ideally people need to be exercising at least twice a week to maintain strength.
“It’s important to exercise regularly, and therefore it’s important for people to find an activity they enjoy to keep them active,” he says.
Of the specific findings of the research, Barback comments, “It doesn’t really matter how slow you go as you get older – the important thing is not to stop!”
The research conducted at Carnegie Mellon University used computer simulations to generate physiologically and physically plausible walking behaviours in order to predict how physiological changes affect gait.
Given that this was a simulation study the results are based on assumptions that may limit its predictive capabilities as it simplifies the human locomotor system and relies on a hypothesized neural control circuitry.
“In the long term, we plan to extend the predictive capability of our neuromechanical simulation framework, for example, to analyze pathological gaits after stroke or spinal cord injury and to prescribe optimal treatment,” says lead researcher, Seungmoon Song.