Atrophy comes for pretty much every part of our bodies, but the effects of time are particularly rough on the knees. Why? Because they’re complicated anatomical machines with a number of moving parts, all of which wear and tear with use.
As we age, the muscles that stabilise the knee weaken, and our bone density drops. The cartilage that cushions the bones wears thin. The ligaments that connect the bone and muscle also become less elastic.
The upshot of all of this, for most of us: stiffness, pain, a reduction in mobility and an increase in the involuntary vowel sounds we make as we get off the sofa.
Like any machine, however, if they’re well looked after, our knees respond in kind. That starts with an understanding of what increases your risk of knee injuries and osteoarthritis.
The natural enemies of good knees include excess body weight, footwear that offers no support and repetitive movements that ask a lot of your joints.
For example, in 2021, French researchers found that parkour athletes sustained an average 1.7 knee or ankle injuries for every 1,000 hours they trained.
Not as bad as you might think, but it’s the long-term damage that accumulates – and it’s not only people who jump off buildings who are at risk.
Research on elite dancers found that knee injuries, such as meniscal tears, are among the most common injuries.
Any movement that involves impact through the legs, or twists the rotation to change direction, is going to ask a lot of the knees. A dreaded ACL injury can keep a footballer off the pitch for up to a year.
But research also suggests that 10 to 20 years after the injury, half of those injured will have osteoarthritis associated with the original damage.
There’s also some debate about whether or not running is good for the knees or bad. It’s said that road running, for example, is akin to hitting the soles of your feet with a hammer for an hour.
But a 2017 study compared the risk of knee osteoarthritis in runners with non-runners and found no significant difference.
In fact, exercise is believed to strengthen your joints – even load-bearing movements. A 2023 study found that people who engaged in strength training are 20-per-cent less likely to suffer osteoarthritis than those who’ve never done it.
Strengthening surrounding muscles, like the quadriceps, also seems to be beneficial. Assuming you’ve bought some well-cushioned shoes and are exercising regularly, the other best-care practice with dodgy knees is to acknowledge any mild discomfort.
Small injuries can develop quite easily into something more serious and long-term. If you do have pain, try wearing a knee support or going swimming.
Some research suggests that, because it’s non-weight bearing, swimming can aid recovery from minor knee injuries and reduce the risk of long-term issues.
This article is an answer to the question (asked by Thomas McPherson, Wakefield) 'How can I look after my knees as I get older?'
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