MOHAMAD AL-ASSI ran beneath the concrete wall as the sun rose over Bethlehem. His Nikes pounded the gravel, his breath fogging the air as graffiti and paint splatter blurred past with each stride.The road along the barrier separating Israel from the occupied West Bank makes up a stretch of a marathon route that al-Assi and thousands of others ran on Friday. The event is open to people in other parts of the world running in solidarity with the Palestinians and another, shorter race was happening in Gaza.