We've got a surefire way to keep the happy feelings pouring in. And you don't have to inhale.

Just grab your workout shoes and get going. Research now confirms it: Sustained aerobic exercise can give you a natural high.

Happiness Is All in Your Head
Researchers recently noted all sorts of endorphin activity when they studied the brain scans of people who'd gone for a 2-hour run. Their emotion- and mood-controlling brain regions were particularly saturated with the feel-good hormones. But you don't necessarily have to run marathons to boost the natural mood-enhancing chemicals in your blood. In fact, you might not need to run at all. Find out how just 30 minutes of walking can lift your spirits.

Got bad knees? No problem. Pick out a few exercises from this gentle-on-the-joints workout.

More Tips for Bliss
There's more than one way to juice up your joy (and make your RealAge younger in the process). Try these other tips:

• Money worries weighing you down? Take this quiz, and discover ways to soothe financial stress.
• Unfinished tasks nagging at you? Use the Daily Life Equilibrium Calculator in this article to get back your feel-good balance.
• Struggling with grief? This article can help you through the process.
• Test your happiness know-how with the quiz at the end of this article.