In 1902, researchers discovered a spike of white cells in the blood of Boston marathon runners. Ever since then, researchers have been fascinated by the connection between exercise and inflammation. There’s no argument that the connection exists — but why? What is going on at the cellular level?
Now, as reported here, a new Harvard Medical School study may offer an explanation.
The study, involving mice, shows that muscle inflammation caused by exertion “mobilizes inflammation-countering T cells, or Tregs, which enhance the muscles’ ability to use energy as fuel and improve overall exercise endurance.”
The article quotes study senior investigator Diane Mathis, professor immunology in the Blavatnik Institute at Harvard Medical School: “The immune system, and the T cell arm in particular, has a broad impact on tissue health that goes beyond protection against pathogens and controlling cancer. Our study demonstrates that the immune system exerts powerful effects inside the muscle during exercise.”
Next step: replicate the findings with humans. But even at this stage, with only mice, “the study is an important step toward detailing the cellular and molecular changes that occur during exercise and confer health benefits.”
From the article: “‘We’ve known for a long time that physical exertion causes inflammation, but we don’t fully understand the immune processes involved,’ said study first author Kent Langston, a postdoctoral researcher in the Mathis lab. ‘Our study shows, at very high resolution, what T cells do at the site where exercise occurs, in the muscle.’
“Most previous research on exercise physiology has focused on the role of various hormones released during exercise and their effects on different organs such as the heart and the lungs. The new study unravels the immunological cascade that unfolds inside the actual site of exertion—the muscle.”
“Our research suggests that with exercise, we have a natural way to boost the body’s immune responses to reduce inflammation,” Mathis said. “We’ve only looked in the muscle, but it’s possible that exercise is boosting Treg activity elsewhere in the body as well.”