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You knew it, science proves it. Exercise can be poisonous

Too much exercise can actually poison your blood. But the amount it takes to get toxic isn't a feat for mere mortals.

If he keeps that up all day, his blood won't be very happy.Cpl. Earnest J. Barnes, US Marine Corps, via Wikimedia Commons

Studies come out all the time that tout the benefits of exercise. It can help you lose weight, live longer, cut stress, strengthen bones and ... yawn ... um, where was I? But just recently I came across a study about exercise that made me drop my doughnut, get out of my recliner and really take notice. According to a study in the International Journal of Sports Medicine, exercise, it seems, can poison your blood.

OK, before you get too excited and put the StairMaster out on the street, we're not actually talking about the healthy kind of exercise. You know, the kind where you walk the dog around the neighborhood while listening to a CNET podcast or lift a few weights in the basement while binge-watching Daredevil on Netflix. We're talking extreme exercise. How extreme?

Well, the researchers -- who hail from various universities in the UK and Australia -- studied what happened inside the bodies of runners competing in a 24-hour non-stop ultra-marathon. That's right -- people who run for 24-hours without taking a break. Because it's fun.

After all of that pavement pounding, the researchers found that the guts in the 17 runners they tested actually got leaky and allowed bacteria to enter the bloodstream where some of them released toxins, according to Scientific American. As a result of those invaders, the runners' bodies initiated an immune response which led to inflammation.

"Some runners actually had blood profiles identical to those of patients admitted to the hospital with blood poisoning, or sepsis," says Scientific American.

Interestingly, the researchers found that the most well-conditioned athletes were able to counter their immune systems' reactions to the extreme exercise by producing anti-inflammatory compounds.

Unfortunately, the research mentions nothing about the mental states of people who run non-stop for a full day. I imagine that would be a study worth reading.

While you might not be embarking on a 24-hour run any time soon, the researchers said that they started seeing an inflammatory response after just four hours. So best to be in good enough shape so that your body can fight back against its own immune system if you're going to embark on a long workout.

It all doesn't really sound worth it to me though. Think I'll just stick with those remote control arm curls for now.