Extreme Exercise Without Training Can Poison Blood

OK, it’s possible, but it’s not likely. When researchers at Monash University in Australia studied the biology of athletes who compete in extreme endurance events, like 24-hour marathons, they found endotoxins–gut bacteria that should be contained to intestines, in the athletes blood. No, it’s not good. HealthDay reports that the researchers took blood samples before and after the extreme events, and found that “exercise over a prolonged period of time causes the gut wall to change, allowing the naturally present bacteria, known as endotoxins, in the gut to leak into the bloodstream.” Why do we care? Because when endotoxins enter the bloodstream, the immune system responds as if the body had a serious infection, causing inflammation throughout the body. And now the good news: the researchers also found that fit athletes –those who follow a steady training program to gradually prepare for extreme endurance events– develop immune mechanisms to counter this threat.