Could running actually be good for your knees?

Controversy exists about the negative and positive effects of running on your knees. Tradition has maintained that running causes an increased risk of osteoarthritis in the knees, but recent evidence in the literature seems to contradict that long-held belief. Most recently, a study published in the European Journal of Applied Physiology looked at inflammatory changes in the knee joints of runners. The data from their study is likely limited in its overall value, but an interesting finding was a decrease in an inflammatory chemical called interleukin-15, which has been associated with increased progression and severity of osteoarthritis. Although not convincing evidence, this does agree with previous studies which found evidence that joint loading triggers anti-inflammatory markers in the synovial fluid from the knees of runners.

Running decreases knee intra-articular cytokine and cartilage oligomeric matrix concentrations: a pilot study; Eur J Appl Physiol, 2016, Oct 3.