Bones & Jointspreliminary · human data
Exercise does not appear to wear down arthritic knees
MRI evidence from nine trials suggests loading the knee through exercise leaves cartilage intact in people at risk of, or living with, osteoarthritis, with a few comparisons even hinting at improved cartilage composition. Evidence quality is low, so treat this as reassurance rather than proof.
What it shows: Reassurance more than proof: a sweep of nine trials that scanned knees with MRI, but the authors rate the evidence quality as low. It mostly rules out obvious harm rather than proving exercise improves cartilage.Systematic review · Br J Sports Med