Running Lowers Inflammation in Knees

The soreness runners experience after a workout is usually passed off as a price paid for a healthy heart. But new research from Brigham Young University found that instead of increasing, inflammation actually goes down in knee joints after running.

“It flies in the face of intuition,” said study coauthor Matt Seeley. “This idea that long-distance running is bad for your knees might be a myth.”

Seeley and his colleagues measured inflammation markers in the knee joint fluid of healthy men and women aged 18-35, both before and after running.

They found that the concentration of two specific markers, two cytokines named GM-CSF and IL-15, decreased in the synovial fluid in the subjects after 30 minutes of running. When the same fluids were extracted before and after situations that didn’t involve running, the levels of inflammation markers were similar.

“What we now know is that for young, healthy individuals, exercise creates an anti-inflammatory environment that may be beneficial in terms of long-term joint health,” said study lead author Robert Hyldahl.

Hyldahl said the study results indicate that exercise may help delay the onset of degenerative diseases such as osteoarthritis.

The study’s results are good news since osteoarthritis — the painful disease where the cushioning cartilage at the end of bones wears down and causes the bones to rub together — affects about 27 million Americans.

In the past, many people believed that running caused knee osteoarthritis. But the Arthritis Foundation says that other studies have found that both walking and running significantly decreased the risk of knee and hip replacement, while other forms of exercise increased it.
One study of runners found that they didn’t have a higher risk of knee arthritis than non-runners.

Other common types of knee pain affect runners, such as patellofemoral pain syndrome (“runner’s knee”), which is often mistaken for arthritis of the knee.

“This study does not indicate that distance runners are any more likely to get osteoarthritis than any other person,” Seeley said. “Instead, this study suggests exercise can be a type of medicine.”

The study was published in the European Journal of Applied Physiology.