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Regular aerobic exercise and meditation are both proven mood boosters, but done together, they're extra effective at combating depression. In the first study ever to examine the two therapies in tandem, the combination approach reduced symptoms of clinical depression by an astounding 40 percent.

To explore alternative, drug-free remedies for major depression, Rutgers University researchers recruited 52 young adults, 22 of whom were clinically depressed, to try a targeted mental and physical training program. Twice a week for eight weeks, the students meditated for 30 minutes, focusing their thoughts inward and paying close attention to their breathing, then hit the treadmill for 30 minutes immediately afterward. Following each hour-long training session, the researchers assessed the participants' emotional states.

By the study's end, everyone — both those who'd been battling depression and those who hadn't — reported significant improvements in mood and anxiety levels. The group also spent less time dwelling on negative situations in their lives than they did before starting MAP training.

Because past studies have shown that both meditation and exercise individually can benefit mood, it makes sense that doing one right after the other would be effective. But the researchers were floored by just how well the combo worked. "We were especially surprised that [the training] reduced ruminations about the past," says study co-author Tracey Shors, a psychology professor at Rutgers's Center for Collaborative Neuroscience. "These thought patterns can be difficult to change." 

It's still not clear exactly how mental and physical training dampens depressive symptoms, but it likely comes back to brain-cell development, a process called neurogenesis. As the researchers write in their paper, depression, as well as stressful life events, hinders neurogenesis, while therapies like SSRI drugs promote it, thereby relieving depression symptoms. Neurogenesis is tricky to track in humans, says Shors, but plenty of animal studies have shown that aerobic exercise also promotes new brain cell development. Additionally, she says exercise increases oxygen and blood flow into the brain, activating any number of biochemical reactions that may boost mood.

As for meditation, "it activates the parasympathetic nervous system, which lessens the stress response," says Shors. "But meditation also has a large learning component. The person who practices meditation consistently learns to understand his own mind and the way thoughts come and go." These learning processes change the brain in a good way, she adds. "Likely, the combination of meditation and exercise is especially effective because the change in autonomic and central nervous system activity is quite profound."

So could this be a viable alternative to antidepressant drugs? Possibly. "Every case is different, so we're not necessarily prescribing MAP Training over antidepressants," Shors says. "But these activities are available to anyone at any time, so they can certainly be incorporated into whatever therapies are already prescribed."