So many times, I hear my patients tell me that they have been told their cartilage is thinning, wearing down, or that they have the dreaded “bone on bone” in their knees. This discussion almost always comes with a warning that they only have so much cartilage left, and that they had better stop squatting, walking on the treadmill, or doing anything that causes any kind of compression in their knees. I’ve even had a patient who reported being told “you only have a certain number of sit to stand transfers left, you should definitely not be working out anymore, you need to save those squats for things like getting on and off the toilet.” This is the absolute wrong message to be sending our patients, and only adds to their fear avoidance behavior while perpetuating misguided beliefs about joint health and what is and is not “dangerous activity.”
In a systematic review and meta analysis (found here), researchers examined the impact of exercise on molecular biomarkers related to cartilage and inflammation in individuals at risk for or with established knee OA. They concluded that “exercise therapy is not harmful, because it does not increase the concentration of molecular biomarkers related to cartilage turnover and inflammation, implicated in OA progression.” Moreover, they found that exercise therapy actually DECREASED molecular biomarkers in 30% of the RCTs involved in the review!
Patients at risk for or with established knee OA should be encouraged to exercise MORE, not less. One of the first steps must be educating these patients about what osteoarthritis actually is, an inflammatory process that involves changing molecular composition of joint components, and that it is not caused by mechanical pounding or stress. In fact, as the research shows, mechanical stress and joint compression may actually be the answer to IMPROVING their functionality and decreasing their pain.