Why Does My Knee Hurt When I Run?

Running is an amazing way to strengthen your muscles, challenge your endurance, increase your cardiac and respiratory abilities, and even release endorphins. But, what happens when something that is so good for your body starts to hurt? Running has an effect on your ankles, hips, spine, and more, but today we will be focusing on one of the effects on the knees. Knee pain can be caused by a wide variety of reasons, but today we will be focusing on range of motion, strength, and alignment.

Your knees have an optimal range of motion that helps with running. If you have too little or too much range of motion, your running form and ability can be impacted. We see many athletes, from kids to teens to older adults, with decreased flexibility in their muscles- especially their hamstrings, quadriceps, TFL, and calves. When muscles are not stretched properly prior to and after running, they can get tight and limit the knee’s ability to bend and extend. Some muscles can also make your knees come closer together (knock knee’d) or further apart (bow legged). This can alter whether the inside or outside of your knee has more compression with each stride- leading to arthritis. Other muscles connect to the knee cap, and when tight or loose can change the alignment of how your knee cap moves with your knee joint. If you have too loose, or weaker muscles supporting the knee, your muscles may not be giving enough support to the joint with running- especially on uneven surfaces.

This may be demonstrated on examination by extra range of motion. Your muscles are the first line of defense for joint protection. When they fail to support your body, other structures like tendons and ligaments have to take the brunt of the force, causing more structural issues with the knee. We often see that people may hyperextend their knee, or have issues with their knee giving out on them with running strides. There are also effects from the ankle and hip that can be affecting knee pain with running.

Whether you are training for the Brew City Marathon in Southeast Wisconsin, aiming for the Lighthouse Run in Racine, or just starting on your treadmill at home, ACS is your premiere place for knee pain evaluation for the running season. We look at your body as a whole, evaluate your running pattern, and help you with an individualized program to get you back in stride. Let’s Run Racine!

Hanna Kearney, PT DPT