Is Running Bad for Your Knees? What Science Says

The odd thing about running for health is that it almost always comes with a warning. Someone will inevitably show up to ruin your day by saying you should enjoy the benefits while they last, because running will eventually grind your knees to dust and destroy their ability to keep you mobile without serious pain. If that claim is true, it is a sad trade of short-term health for constant pain in your final decades. If it is false, and you let this myth stop you from running, then you may have been cheated out of years of great, health-boosting workouts by a misreading of the facts. So what is the truth? Is running really bad for your knees, or is it a cardiovascular activity you can enjoy fearlessly without worrying about paying a price later in life?

During runs of any distance, especially long training runs, your knees take in the accumulated effect of possibly thousands of foot strikes against the ground, treadmill, or whatever surface you run on. When your knee is narrowly defined as just the kneecap area apart from nearby supporting muscles and tissues, then your knee absorbs running’s impact within its tibiofemoral and patellofemoral joints. While much of the impact is indeed absorbed in the patellofemoral joint in particular, a large share is spread through your quadriceps, and also through your calves, glutes, and hamstrings. Because of this, your knees are better shielded from the full force of impact during runs than most people realize.

Most people misunderstand the structure of the knee. Many runners, including experienced ones active for years, believe cartilage is an unresponsive tissue that breaks down with each use. In essence, the common belief is that tiny bits of cartilage are worn away by every training run, and that all runners’ knees will eventually reach a day when they are weakened beyond repair. This could not be further from the truth. Several studies have concluded that running actually reduces knee pain in various ways. This includes lowering inflammation around the knee, increasing knee cartilage volume in habitual runners, and ultimately reducing the likelihood of osteoarthritis in your knees. In fact, running is one of the best activities you can do if you want to extend the viability of your knees and your body overall.

Just because running benefits knee health under ordinary circumstances does not mean running can never cause knee pain. It remains true that running can cause significant knee pain, though that pain usually appears only when one or more mistakes push your running beyond the bounds of ordinary moderated training. Specifically, when people move quickly from little running to a lot of running and jump into high-mileage runs, they often face a host of problems caused by a sharp rise in mileage before their bodies have had a chance to adapt or adjust. This most often shows up as runner’s knee, usually caused by repeated impacts on the knee combined with weaknesses in the supporting muscles.

As much as you may want to join the ranks of marathon runners within a single week of dedicated training, keep in mind that new runners are often advised to take up to a full year to condition their bodies to handle the rigors of running. In other words, you truly cannot expect to fast-track your pursuit of a marathoner’s body without your body paying a hefty price. More often than not, your knees will be the first part of your body to tell you that you are overdoing it. To prevent this, increase your running mileage very gradually so your muscles and cartilage can adapt to the thousands of impacts they face. Second, do not neglect nutrition during this endurance-building process. While most emphasis will rightly go to hydration drinks and other solutions with electrolytes, which improve muscle signaling and extend your runs, do not neglect your joints. To keep your knees healthy, collagen peptides are a proven way to preserve the structural integrity of your knees and repair them after hard training bouts.

As is often the case, the details of how you run play a major role in whether you eventually feel knee pain, either briefly or chronically. Above all else, remember that there is a slow and steady path to building your running conditioning, and this includes a strategic approach to both training and nutrition that considers the health of your knees. Knee pain is often cited as an inevitable result of frequent running. The common source of lower-body discomfort during running is the impact of your feet on the ground being absorbed throughout your body, including your knees. Cartilage is a living tissue that responds to running by gradually growing larger and stronger; it does not erode the way many people think. The muscles of your legs also grow stronger in specific ways that make them better at absorbing running’s impact. Most knee pain caused by running comes from dramatic increases in running volume before your cartilage and muscles can adapt. To avoid knee pain, gradually increase your training volume, and consider supplementing with collagen peptides, a protein source that specifically strengthens joints.