<http://schema.org/description>
"First-time and even experienced marathon runners know it all too well:  the feeling that hits around mile 20 when your legs begin to give way and you feel as if you would die if you moved another step.  What&amp;#039;s going on here, and what can you do to avoid it?"^^<http://www.w3.org/2001/XMLSchema#string>
<http://adventure.howstuffworks.com/outdoor-activities/running/training/hitting-the-wall2.htm>