Knee pain isn’t just a problem for old people: It can hit at any age, says Matthew Abdel, an orthopedic surgeon and associate professor at the Mayo Clinic.

And it’s happening more and more frequently. According to a study from the Boston University School of Medicine, the prevalence of knee pain has increased significantly over a 20-year period. Currently, one in five Americans have suffered knee pain, and it’s the culprit behind a third of all doctor’s visits for muscle and bone pain, says Stephen Nicholas, founder and current director of New York Orthopedics.

That’s one reason why there are roughly 700,000 knee replacements annually. But who wants to go under the knife if you don’t need to? Thankfully, there are things you can do right now to protect your knees to avoid that fate. Here’s the lowdown.

Knee Wrecker #1: Skipping Your Warmup

We know you’re strapped for time, and you want to make the most out of your run. But jumping right into a workout could really mess up your knees.

That’s because warming up lubricates the knee joint, circulates synovial fluid into the knee, improves muscle elasticity, and boosts oxygen flow to the area – reducing your chance of injury to the knees, according to Dr. Nicholas.

Knee Saver: Stretch Before Your Workout

“The most important thing you can do for your knees is give yourself an appropriate warm up period,” says Dr. Nicholas. “Stretching your lower legs is particularly key for long term running health. When the muscles are unevenly lengthened, the knee caps pull to the side, which causes wear or pain on the joint.”

Set aside at least 10 minutes before your workout to work on stretching, says Astrid Pujari, M.D., an integrative internist based in Seattle and author of The Healthy Knees Book. “Warming up lets your muscles gently strengthen, which is key for healthy knees,” she says.

The best warmup, says Dr. Nicolas, is a combination of low level cardio-activity, such as jogging or jumping jacks coupled with dynamic stretches that accentuate the motion you are targeting.

Then, when it comes time for your workout, make sure to include exercises that strengthen the muscles around your knee, like the quads, as well as your core, glutes, and abdominal muscles, says Dr. Pujari. This will help your knees with stability and mobility.

That’s important, since knees need a full range of motion – to move back and forth, twist a little, and pivot. This will protect you if you find yourself in an awkward position; increased flexibility stresses the joint less.

Knee Wrecker #2: You’ve Packed On the Kilos

As the largest load-bearing joints in our body, knees suffer mightily when you gain weight.

“Being overweight or obese will definitely wreck your knees,” says Dr. Abdel.

That’s because whenever you walk – and especially if you’re going up stairs – the load on your knee is several times higher than your weight. The increased pressure means more overuse on the knees, slowly degenerating the cartilage of the knee and increasing the risk of injury and subsequent inflammation.

Knee Saver: Lose Weight Safely

If you lose five kilograms, your knees experience 13 to 22 kilograms less weight when you go up and down stairs. If you lose 22 kilograms, your knees experience 110 less kilograms of force when you take on stairs, Dr. Abdel says.

So losing weight is obviously a benefit to your joints. But you have to do it carefully. Running too fast or too hard can increase the risk of stress fractures and tendonitis.

Lose weight with the 12-week Run It Off training plan!

Opt for a lower intensity workout at first, for a longer duration, until you lose some weight. Once your body mass index approaches normal, your knees should be better able to withstand the impact of harder running, Dr. Nicholas says. Work back into running gradually, increasing your intensity and duration over a six-week period rather than trying to immediately recover your previous mileage levels.

Diet matters, too. Choosing a diet high in fruits and vegetables – and low in processed foods – can help keep your weight down. And it’ll also boost your intake of antioxidants, which can help counteract the inflammatory effect of too much extra weight, says Dr. Pujari. Choose as colourful a plate as possible – that’ll ensure you get as many different kinds of antioxidants as possible, which have different anti-inflammatory benefits.

Knee Wrecker #3: You Overdo Pounding the Pavement

Yes, you want to exercise to help your health, but going too hard, too quickly, for too long can spell danger for your knees – especially if your joints are already vulnerable.

“Think of cartilage the way you would your tyres,” says Dr. Abdel. “If you ran 80 kilometres every single day, just like tyres on a car, it will wear away the cartilage and lead to arthritis.”

One recent study from the University of Kentucky found that up to 70 percent of new runners will develop some kind of overuse injury within any one-year period. An example, of course, is runner’s knee, an irritation of the cartilage in the kneecap that leads to inflammation and pain.

On the other hand, a new study from Brigham Young University found that running may actually be good for your knees. But there’s a caveat: The study was skewed in favour of people who had never had knee injury or knee pain, making it an elite group of participants instead of the more typical population, many of whom are predisposed to injury.

So, what’s the bottom line? You need to listen to your body.

“Pain is a good sign it’s time to back down and avoid overuse,” Dr. Nicholas says.

And if you do find yourself aching after a run, that’s telling you it’s time to visit your orthopedic surgeon. He can check you out to make sure that your pain isn’t causing any kind of structural damage – which, if you continue doing what you’re doing, you can make worse and lead to long-term harm.

Knee Saver: Keep Breaking a Sweat – but Safely

No, don’t take this as an excuse to pause your exercise routine. In fact, that’s one of the worst things you can do.

Not exercising can actually make knee pain worse. “Exercise keeps the joint lubricated and keeps the muscles around the knee strong,” says Dr. Abdel. “That way, the knee joint itself doesn’t bear the largest load, because the muscles, ligaments and tendons all take a share.”

For optimum knee health, Dr. Pujari recommends milder exercise that focuses on core strength, such as Pilates, yoga and even martial arts.

Want to keep running? You probably don’t need to stop completely. Just don’t overdo your mileage, and pay attention to your shoes. Keep at least two pairs in your rotation, says Dr. Nicholas.

“If you run daily, the cells of the shoes may not recover their elasticity by your next run. That means there’s less cushion, which can damage your knees over time,” he says.

Knee Wrecker #4: You Push Past Your Limits

Yes, you want to get faster and build endurance. But excessive exercise past the point of fatigue in can make you more accident – and injury-prone.

“When fatigue sets in, the different parts of the knees get stressed,” Dr. Nicholas says. And that can lead to injury.

Knowing your limit is critical to avoiding future pain and damage, he says.

Knee Saver: Listen to Your Body

Don’t underestimate the power of rest – it helps your body adapt and integrate the demands of your chosen activity. According to Dr. Nicholas, people who rest every third of fourth day have more productive exercise routines than those who exercise daily.

A day off clears away the inflammatory mediators circulating in your blood stream and eliminates any residual fatigue, giving your knees a chance to completely recover.

The article ​4 Ways Young Guys Are Wrecking Their Knees – and How to Save Them Instead originally appeared on Men’s Health.

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