IF IT'S GOOD FOR THE RODENTS...

For years doctors have recommended exercise to enhance our moods, but the reason it actually works has never been that clear. Thanks to a group of overworked rodents, we may be closer to finding out, and it's pretty good news.

Researchers at Princeton University recently conducted a study comparing sedentary rats with active ones. Both were dunked in cold water, which they really hate (uh, yeah, who wouldn't?). It turns out that even though all the rats were equally stressed out swimming around in frigid water, the brain activity of the more active rats was calmer overall. Scientist Michael Hopkins explained it to the New York Times this way:

The "cells born from running," the researchers concluded, appeared to have been "specifically buffered from exposure to a stressful experience." The rats had created, through running, a brain that seemed biochemically, molecularly, calm.
"[T]he positive stress of exercise prepares cells and structures and pathways within the brain so that they're more equipped to handle stress in other forms."

Though it will no doubt take a lot more research to understand whether or not the same effects result from exercise with the human brain, remember its seeming stress-busting effects the next time you don't feel like working out. When things get stressful as work, your stress-resistant exercise cells may help you remain cool as a cucumber.