Everyone is familiar with stress. We all experience it on one level or another. It is our reaction to any situation that frightens or worries us. These triggers vary greatly from person to person. In response to a trigger, our bodies release hormones that increase heart rate, produce rapid breathing and increase our alertness and awareness.

Short-term bursts of stress are not necessarily bad; in fact, they can trigger chemicals that can improve your memory, increase your energy, and cause you to become more alert and productive. If you're a zebra, and a hungry lion is chasing you across the savanna, the resulting adrenaline makes you run faster, think quicker, and swiftly remember how you saved your skin the last time.

However, zebras, and most other mammals for that matter, don't suffer chronic stress the way humans do. Once the zebra escapes from the lion, his stress is over (until the next predator comes along). Zebras don't have mortgages, traffic jams, or unpaid overtime. They don't worry about paying the bills, getting sick, or being accepted into a good college. It's chronic stress that is such a threat to human health.

Chronic stress (living under stressful conditions for long periods of time) can have a profoundly negative impact on your body. When we experience a threat, whether it's physical or psychological, our bodies go into overdrive. Activity in the sympathetic nervous system rises and the adrenal glands release the hormones epinephrine (or adrenaline) and norepinephrine into the bloodstream. At the same time, the adrenal glands also release cortisol, a hormone that sends the body the message to release fatty acids for a burst of energy.

This nervous system and hormonal activity causes digestion to slow down, blood sugar levels to rise, and the heart to pump more blood to the muscles. This is useful when a car is swerving toward you, but damaging when these hormones are in overdrive too often. Not only does chronic stress contribute to stomach problems, constipation, diarrhea, and more frequent colds and respiratory infections, it can also undermine long-term health.

This illustration shows how chronic stress can result in chronic tension and pain in your body. Each element can add to or start the cycle, and each event reinforces the other.

"A critical shift in medicine has been the recognition that many of the damaging diseases of slow accumulation can either be caused or made far worse by stress," writes Robert M. Sapolsky, author of the critically acclaimed Why Zebras Don't Get Ulcers. "Stress can wreak havoc with your metabolism, raise your blood pressure, burst your white blood cells, make you flatulent, ruin your sex life, and if that's not enough, possibly damage your brain."

"What's important to remember," writes Sapolsky, a professor of biological science and neuroscience at Stanford University, "is that effectively managing your stress can be a powerful weapon against serious illness."

Bodywork such as massage and CranioSacral Therapy can help you break the stress cycle and develop healthy and productive responses to the stressful challenges in your daily life.