What To Do if Your Knees Hurt When Running

Female and male runners who know how to avoid knee pain while running are racing during a marathon


Whether you’ve recently started running as a hobby or you're a marathon veteran, sometimes your knees hurt when running. Is that just part of being a runner, or is it possible to prevent that pain? Knee pain while running is common, but it’s not always simple to understand. 

Knowing how to prevent knee pain when running requires an understanding of how the knee works, and common types of knee injuries. Then, all that’s left is to apply the necessary treatment(s) and prevent future injury. 

Let’s start by zooming in on the knee joint.

The anatomy of the knee joint

The knee joint works like a hinge, allowing a specific range of movement to stretch and bend the leg so we can sit, squat, walk, jump, or run. 

There are variety of components that make up the knee joint:

  • Bones, like the tibia, femur, or patella (kneecap), which provide rigid strength.
  • Cartilage, collagen-rich shock-absorbing tissue that stops bones from coming into direct contact.
  • Muscles, like the hamstring and quadriceps, which can contract and relax to allow movement.
  • Tendons, collagen-rich connective tissue that link muscles to bones.
  • Ligaments, collagen-rich connective tissue that links bones together.

When we exercise, the physical motion causes a strain on our muscles, tendons, and ligaments. The individual protein cells are precisely woven together in a strong collagen matrix, but the individual cells themselves need to be replenished with new collagen protein over time.

In essence, this is why we feel sore after exercising. Our body is hard at work replenishing damaged protein cells in our muscles, tendons, and ligaments. So how does it do this? 

How does the body take care of itself?

Often, with regular intense exercise, the body is stimulated to add more protein (and in particular, collagen protein) to a muscular area of the body. As a result, we become stronger. This explains why you build muscle when you are in a routine of working out.

Feeling sore during or after a workout is normal, but as exercise breaks down the existing protein, what’s left behind now takes on a larger proportion of the physical strain. This creates a vicious cycle, because connective tissue is more likely to cause serious injury if it’s suddenly doing more work than it’s used to.

When your body is in a constant cycle of recovery, paying attention to signals from the body, like knee pain while running, is important. Taking a break at the right time can prevent you from pushing too far and causing a serious injury as a result.

Unfortunately, we aren’t always the best at listening to our body’s signals, and sometimes, we don’t receive the signals until it’s too late! 

You may have heard people talking about “runner’s knee,” and this is the most common cause of  having your knees hurt when running.

But there are many different types of runner’s knee, since it’s simply the name for the overall pain – not the specific condition. There are many parts of the knee and if any one of those parts isn’t functioning properly, that can make your knees hurt when running. 

So what is “runner’s knee” pain exactly? 

Different types of runner’s knee

Here are a few types of runner’s knee that may make your knees hurt when running:

Chondromalacia patella (CMP)

CMP is a chronic condition that causes this cartilage in your knee to break down. This can absolutely make your knees hurt when running.

CMP may be caused by an overuse of the knee, alignment problems, injury, or simply aging. Pain will be particularly acute when going up or down stairs or when sitting with your knees bent for long periods.

Patellar tendonitis (Tendinopathy)

This version of knee pain is sometimes called jumper’s knee. If you overstress your patellar tendon, it will cause your knees to hurt while running or jumping. It may also cause stiffness and a loss of strength in the knee. 

IT band syndrome (ITBS)

Your iliotibial (IT) band is the name for a tendon that connects your knee to your hip. Overstretching or overusing this tendon puts a strain on its ability to effectively stabilize your knee and posture. 

If the side of your knees hurts when running, then it may be because this band has tightened too much and has become irritated or inflamed.

ACL and PCL injuries

If swelling or a popping noise accompanies the feeling that your knees hurt when running, then pause your exercise and pay close attention to your knees.

ACL and PCL tears are most likely to take place if you stop suddenly, or if you change direction. You will probably feel your knee give way from under you because the knee has lost its stability and overall structural integrity.

Kneecap bursitis

The cushioning sacks between bone and soft tissue in the front of your kneecap can become inflamed. This swelling in a cramped area adds unwanted pressure to your other knee parts. 

It’s more of a concern for athletes with repetitive movements; where the type of mobility causes repeated friction in the area. Muscle tightness or a sudden physical injury can also bring on this added swelling. This swelling would certainly result in knee pain while running.

Kneecap subluxation

It is possible that the patella can be pulled to the side (subluxation) or dislocated entirely from its position over the knee joint. This is one of the more instantly identifiable versions of “runner’s knee.”

This happens because the supporting tissues can be stretched or even torn as a result of the subluxation. As well as the pain, there will be swelling and a popping sensation.

Medial meniscus tear

If your knees hurt when running, you may have sustained a tear to the cartilage in your knee joint on the inside of your knee. 

The most likely cause of a meniscus tear is twisting your knee when your foot is on the ground, however it can also occur through a direct impact in the case of a contact sport - or through gradual degeneration with age.

Plica syndrome

The plica refers to a fold of soft inner lining in the knee joint. It can be more prominent in some athletes over others. If this lining of the knee joint is irritated or inflamed this will cause knee pain.

Plica syndrome is most often aggravated through a repeated bending and straightening of the knee. Running in particular can cause plica syndrome because of the requirement for repetitive motions in the legs.

Knee stress fracture

Another potential cause of “runner’s knee” that will make your knees hurt when running, is a stress fracture. A stress fracture is more likely to occur when a runner takes on an unfamiliar surface, uses unsuitable equipment, or pushes their training too far.

So now we know that if your knees hurt when running, there are a variety of potential problems behind it. The important thing for athletes is to take ownership of their own healing. 

If you feel something is wrong with your knees, it is important to seek out medical assistance to get a proper diagnosis and treatment plan. 

How can runner’s knee be diagnosed?

If you visit your medical professional saying that your knees hurt when running, the most powerful diagnosis tool is a full physical examination of the knees and potentially an x-ray. You may be recommended to a physiotherapist who will give you targeted exercises to work the knee back to good health. 

Once you have a diagnosis, your treatment plan can vary greatly. But in general, there are a few treatments you can try once given the okay by a medical professional. 

What to do if your knees hurt when running: 8 treatment options

Time is the most important factor in healing. Effective healing can be summed up as giving your body the resources it needs to help piece itself back together. Here are some of the treatment options available if your knees hurt when running.

1. Rest

Avoid making your injury worse. If your knee hurts when running, it’s a sign that it’s currently less able to take the strain of harsh exercise, and further injury is more probable.

Rest doesn’t just mean limited exercise however. Sitting or standing for long periods of time aren’t considered workouts, but if you are adding pressure or weight to your knee, that isn’t considered effective rest for healing either. 

Measured amounts of rest is also one of the top tips on how to prevent knee pain when running 

2. Ice

Icing an area to ease swelling is a great way to reduce having your knees hurt when running. Using temperature to limit swelling is a great alternative if you want to reduce a dependency on medication. 

Try applying ice for 20-30 minutes every 3-4 hours for two or three days, or until the pain subsides.

3. Compress

Wrapping your knee with an elastic bandage, patellar straps, or compression sleeves can provide extra support for the injured area.

Remember: The wrap doesn’t heal you in any way, so you should still treat your knee like it is injured. Wrapping should be combined with healthy resting patterns. Then, you can slowly build back to your previous routine – avoiding physical risks that increase your likelihood of reinjury.

4. Elevate the leg

Simple and effective, tried and true, elevating your leg on a pillow when you sit or lie down discourages a buildup of blood in that area and provides a level of pain relief. 

Make sure that your leg is in an elevated position while you’re resting – ideally above your heart level. 

5. Take medication

If needed, NSAIDs can provide pain relief. These are best used sparingly on “bad days” when pain relief is most necessary. This is because these medications can put you at higher risk of bleeding and ulcers. 

If you have concerns about the quantity of medication you should be taking, your medical professional is the best port of call. As well as advising about over-the-counter medication, they may prescribe stronger medication for more severe knee troubles.

6. Try stretching and strengthening

The hamstring and the quadriceps function best when they’re kept in good condition. Stretching allows muscles to gradually build flexibility over time and prepares them to face the demands of exercise.

Your doctor can refer you to a physiotherapist who can provide a regimen of gradual mobility and training exercises for your joints.

Like good resting habits, stretching properly is also high on the list of tips on how to prevent knee pain when running.

7. Invest in good-quality footwear

The fastest way to ruin your knees when running is by wearing incorrect footwear. If your knees hurt when running, you should check to see if your running shoes are suitable for you. Arch supports or orthodontics are options to consider.

Proper running shoes also lose their strength and support over time. If your knees hurt when running and you have been wearing the same training shoes for over a year, that could be the issue. 

8. Ensure proper nutrition

Your diet plays a large role in the overall health of your body, and your knees are no different. Ensuring you eat a balanced, nutrient-dense diet can go a long way to helping you if your knees hurt when running. As such, it’s important to follow nutrition tips for runners.

One of the best supplements you can add to your routine is collagen. Collagen protein is the body’s building block of choice when providing tensile strength to ligaments and connective tissue. It’s a crucial piece in the puzzle of healing.

With that in mind, collagen supplementation may be the answer to preventing knee pain when running. Collagen will provide your body with what it needs for healthy protein regeneration in ligaments and connective tissue. 

Why do athletes take collagen? If your knees hurt when running, it could make all the difference. Collagen is one of the preferred supplements for endurance athletes because it helps you exercise for longer and recover faster, as well as protecting you against injury. 

When choosing your collagen supplement, you want to look for hydrolyzed collagen. What is hydrolyzed collagen? It’s collagen that has been broken down into smaller, more bioavailable pieces so your body can make use of all the benefits of collagen for your knees. 

By using the “R.I.C.E” method, practicing proper stretching and strengthening, ensuring you have a balanced diet, and taking a daily hydrolyzed collagen supplement, you’ll be well on your way to preventing knee pain while running. 

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