Exercise Keeps Your Cells From Turning Into Hoarders

There are so many good reasons to exercise already, but a new study has found one that might be particularly motivating for anyone who's ever been permanently scarred by an episode of Hoarding: Buried Alive. Exercise can keep your cells from becoming tiny hoarders! Seriously. A new study, done by scientists at the University of Texas and published in Nature, has found that exercising maximizes your body's ability to keep itself clean.

Did you even know that your body gets dirty on the cellular level? It sure does, just like your house. The New York Times explains:

[C]ells accumulate flotsam from the wear and tear of everyday living. Broken or misshapen proteins, shreds of cellular membranes, invasive viruses or bacteria, and worn-out, broken-down cellular components, like aged mitochondria, the tiny organelles within cells that produce energy, form a kind of trash heap inside the cell.

Ick. Fortunately, there's a process called autophagy (which means "self-eating") that cells use to clean up after themselves. It basically involves a special membrane that traps junk and then carries it to the part of the cell called a lysosome, where it's either recycled or burned for energy. It would be awesome if we could install a similar mechanism to make our houses self-cleaning.

If autophagy didn't exist, our cells would quickly become the biological version of hoarders, slowly burying themselves alive in whatever the cellular equivalents of unfinished craft projects and cat corpses are. And it turns out, scientists think, that something going funky with your self-cleaning system might actually be what causes diseases like diabetes and Alzheimer's.

Researchers know that autophagy responds to starvation and stress by speeding up. So, they theorized that since exercise is a form of physiological stress, and autophagy is affected by that very kind of stress, that perhaps exercise affects autophagy. To test this they had some mice run (hopefully on miniature treadmills with very tiny iPods) and measured how many of the special autophagy membranes they had. After just 30 minutes of running, their cells had a lot more of the necessary membranes.

To try to explain how a more efficient cleaning mechanism increased well-being in the mice, the researchers created a new strain of mouse that had an autophagy mechanism that didn't respond to stress. So no matter how much a mouse ate or exercised, they'd have the same level of cellular cleaning going on. When these new mice ran, they got tired quickly, when compared to a control group of normal mice, and their muscles couldn't get sugar from their blood in the same way the normal mice could. When they ate high-fat diets, the modified mice got diabetes and so did the normal mice. But then when both groups started running, the normal mouse group got rid of its diabetes, but the modified mice could not get rid of theirs.

So the researchers concluded that "an increase in autophagy, prompted by exercise, seems to be a critical step in achieving the health benefits of exercise." It's hard to know exactly how directly these results can carry over to humans, since our autophagy systems are very difficult to study. But Dr. Beth Levine, one of the researchers, points out that if this theory works, you've got to be active to experience the benefits of boosted autophagy. Both groups of mice had "normal background levels of autophagy" happening when they weren't exercising, but that level wasn't enough to ward off something like "diabetes in the face of a poor diet." The mice were only able to keep diabetes at bay when they could get their cleaning system running at very high efficiency by exercising.

In other words, if these conclusions hold for humans, you've got to get moving and become a kind of neat freak about making sure your cellular house is cleaned religiously. Busting out a Swiffer once a month probably isn't going to cut it. Otherwise, you could end up starring in an extremely gripping episode of TLC's Extreme Cell Hoarders where everyone gasps and tweets about all the horrifying shit they found lying around in your body.

Exercise as Housecleaning for the Body [New York Times]

Image via Sebastian Kaulitzki/Shutterstock.