Have You Experienced an Endorphin Rush or "Runner's High" During Exercise?

Researchers have slowly been gathering evidence that the famed "runner's high" really does exist. Most of their work supports the idea that the feeling of euphoria and well-being some athletes experience during exercise, is actually related to an increase in endorphin levels in the brain during exercise.

What about you? Have you experience this sensation during exercise?
Tell us about it. Share your runner's high experience with the rest of us.