If you're interested in living a healthy lifestyle, then some kind of aerobic exercise needs to be a part of it. If you have healthy knees, feet and ankles, then running is a great option to meet your aerobic needs. Running has all kinds of physical benefits for the human body, including lowering your blood pressure, fighting bone and muscle loss and helping you drop a few pounds. Flexibility, sustained energy and a strong heart and lungs are also perks of running just a few days a week. And these are just the physical benefits. There are also a number of pluses for your mind.

Everyone gets the blues now and then, and some people are a little moodier than others. But depression is an entirely different scenario. In fact, it's the leading cause of disability in the United States for people between the ages of 15 and 44 [source: National Institute of Mental Health]. If you suffer from depression, you experience prolonged periods in which you're crippled by empty, sad feelings. There are many different kinds of depressive disorders -- for example, dysthymic and bipolar disorders -- but they all generally involve malaise, sadness, guilt, fatigue and irritability, and frequently can lead to eating disorders, insomnia and even suicidal thoughts. This is why depression is so much more than a psychological state. It affects every part of a person's life and makes a big impact on a person's physical health.

So where does running come in? Achieving a physical goal, like running a 10K, is great for someone suffering from depression because depressed people generally have poor self-images. And beyond the goal-oriented therapeutic benefit, endorphins can really help pick up a person's mood. Endorphins, the "feel-good" hormones of the body, have a lot of things going for them. These naturally occurring opiates can make you feel better physically by helping to quell pain. They also slow your aging process, give you stress relief and send your immune system into overdrive. When you run, a flood of endorphins are released. Scientists aren't quite sure what triggers this release, but they do know that prolonged exercise, along with things like orgasms and chocolate, will do the trick.

If you get in shape and run long enough, you may even experience the "runner's high" that comes with endurance training. A runner's high is a euphoric feeling triggered by an overload of endorphins -- in other words, just about the opposite of depression. Unfortunately, it's not something that stays with you, and while running can't cure depression, it can give you a temporary lift from depressive feelings, which can do a lot of good for someone suffering from such a disorder. And it's not just running that spurs the release of endorphins; all exercise does this.

One of the major components of depression is inactivity. Sitting inside with the curtains closed is only going to keep someone in a depressive state. Getting out and hitting the road for a run can be a great first step to help deal with a depressive disorder.