That might be true in the extreme ends, say for Ironman athletes, but a bit misleading as a summary since we already have lots of data that moderate exercise co

That might be true in the extreme ends, say for Ironman athletes, but a bit misleading as a summary since we already have lots of data that moderate exercise correllates with reduced risks of everything from getting a cold to heart disease. If we’re comparing to people who don’t exercise, the alternative should be moderate exercise, not high intensity training. Also a bored and over-reactive immune system can be a pretty bad thing.