People don't high five when they're stressed.

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In general, exercise is a fundamental part of leading a healthy and fit life. Even if you're thin, you aren't in good shape if exercise isn't a part of your routine. The body just needs it. If you're overweight, there aren't many better ways to lose it than by beating the pavement with a brisk walk or run. Running can help you shed as many as 100 calories per mile and aids in lowering your blood pressure by making sure the arteries stay nice and elastic. In fact, running can cause your arteries to expand and contract as much as three times the arteries of a guy who spends all his time sitting at his cubicle. Running also slows down the hands of time a little, as it relates to your aging process -- regular runners are less likely to have bone and muscle loss. This is because as we age, bones can either grow stronger if they're worked out, or weaker, if you're a couch potato. The sedentary lifestyle can lead to osteoporosis. The active runner will remain strong and flexible.

Those are just a few of the physical benefits of running. As you probably figured, there are some psychological benefits for runners as well. Stress in both its forms, acute and long-term, have some pretty nasty effects on your body. Acute stress comes on fast and typically doesn't last very long. It can be triggered by anything, from an auto accident to bumping into an old flame you weren't prepared to see. Most of your body systems are negatively affected by acute stress. Your brain, lungs, heart, immune system and digestive system all ramp up to deal with whatever trigger got you so worked up, whether it's a real danger or just perceived. Long-term, or chronic, stress is even worse. Over time, your heart will have to work overtime, and your immune system will weaken and send your fat straight to your waistline. Arthritis, heart disease, diabetes and aging all take a hit when you live with chronic stress.

If you lead a hectic and stressful life, take heart -- running can be your friend. Psychologically, running gives you a set amount of time to be alone with your thoughts. If you're able to use this to your advantage, you can use that time to get your brain around an issue at the office or the problem with your significant other. In studies, regular runners generally say they live a happier, more stress-free life than their housebound counterparts. Aside from simply being happier because you're in better shape and feeling good, endorphins play a big role in these results. You might know endorphins as the "feel-good" hormones of the body. It's an opiod chemical that the body uses to help quell pain. They also help slow the aging process, relieve stress and anxiety, and enhance the immune system. And you guessed it -- running can release a flood of these endorphins.

There are also some psychological benefits to achieving physical goals, so the next time you feel stressed, hit the road and run for about 20 minutes. You may be surprised at how much it helps your anxiety level.