Live Longer Habits

Based on an article by Hunter Bennett, Lecturer in Exercise Science, University of South Australia. Originally published on The Conversation.

You’ve probably heard people say running is bad for your knees – that all that pounding will wear them down over time. But is that really true?

Running is a high-impact activity, yes. Each time your foot hits the ground, your body absorbs forces two to three times your body weight. That means your knees take on about three times more load when you run compared to when you walk.

But here’s the twist: this isn’t necessarily harmful. In fact, it might be good for you.

Your knees are designed to move

Our bodies aren’t fragile machines that wear out with use – they’re living, adaptive systems. The tissues in your joints, including cartilage, respond to stress by strengthening. Cartilage is a tough yet flexible material that cushions and protects your bones.

When load is removed from the body (like during bed rest or after injury), both bone and cartilage can actually weaken. In other words, your knees need movement and load to stay healthy.

What running does to your joints

Running does temporarily reduce the thickness of knee cartilage, but research shows it returns to normal just a few hours after the run. This process might actually help nutrients move into cartilage, keeping it stronger over time.

Studies have found:

• Runners tend to have thicker knee cartilage than non-runners.
• Runners generally have better bone density than non-runners.
• Regular running may even lower your risk of developing osteoarthritis, though more research is needed.

Put simply: running doesn’t destroy knees – it may protect them.

Am I too old to start running?

There isn’t much direct research on people who begin running later in life. However, related studies give us encouraging clues.

For example, a 2020 study showed that adults over 65 who took up high-intensity jump training (which puts even more stress on joints than running) found it both safe and beneficial. They improved strength, function, and enjoyment.

That suggests starting running later in life is safe too – as long as you begin gradually.

Tips if you’re starting out later in life:

• Begin with intervals: alternate short periods of walking and jogging.
• Progress slowly: let your body adapt before adding more distance.
• Focus on consistency rather than speed.

Why does running have a bad reputation?

The main reason is injuries. Almost half of all runners experience some kind of injury each year, often in the knee. But most of these are overuse injuries – caused by doing too much, too quickly, without giving the body time to adapt.

Here’s how to lower your risk:

• Increase gradually: avoid ramping up mileage by more than a couple of kilometres per week.
• Fuel your body: running burns a lot of energy. Eat enough carbohydrates and protein to recover, and ensure you’re getting calcium and Vitamin D for bone health.
• Vary your surface: grass is softer than concrete, so try running on grass a couple of times a week when starting out.

The bottom line

Running isn’t the knee-destroying activity many believe it to be. On the contrary, it can strengthen your joints, bones, and overall health – at any age.

If you’re starting later in life, the key is to build up slowly, fuel your body well, and listen to your limits. With those precautions, the benefits of running far outweigh the risks.

source:theconversation