The following is a summary of “Is running good or bad for your knees? A systematic review and meta-analysis of cartilage morphology and composition changes in the tibiofemoral and patellofemoral joints,” published in the February 2023 issue of Osteoarthritis and Cartilage by Coburn, et al.

Although running has been shown to have numerous health benefits, some people worry that it may hasten the onset and worsen the symptoms of osteoarthritis. The purpose of this study was to carefully analyze the impact of running on hip and knee cartilage as measured by magnetic resonance imaging (MRI), both immediately (within 20 min) and later (20 min-48 h). Method Studies were identified that used magnetic resonance imaging to compare the amount of cartilage damage in the hips or knees before and after a runner took part in the activity. In addition, the potential for bias was measured with a modified version of the Newcastle-Ottawa Scale. 

Random-effects meta-analysis was used to determine the percentage changes in cartilage results. Using the Grading of Recommendations Assessment, Development, and Evaluation technique, the reliability of the available evidence was calculated. About 446 knees were the only joints examined in 24 investigations. Nearly 1/3 of the studies had a moderate or low chance of error. The amount of weight-bearing femoral cartilage fell by 3.3% (95% CI: 2.6%, 4.1%), and the volume of patellar cartilage reduced by 4.9% (95% CI: 4.43.6%, 6.2%) in the first 24 hours after running. 

The femoral trochlear cartilage saw the greatest decrease in T1 and T2 relaxation durations, by 13.1% (95% CI: -14.4%, -11.7%), immediately after jogging. T2 relaxation times in the tibiofemoral cartilage returned to pre-injury levels after only 91 minutes. Within 48 hours of finishing a run, pre-existing cartilage abnormalities did not improve. Very low-quality evidence suggests that running instantly reduces patellofemoral and tibiofemoral cartilage thickness, volume, and relaxation times. Changes in hip cartilage are unknown, but changes in knee cartilage appear minor and temporary, suggesting that a single run does not damage knee cartilage.