Silsilat al-Ahadith al-Sahihah

It is narrated from Sayyidah Umm Walad Shaybah (may Allah be pleased with her), she says: I saw the Messenger of Allah (peace and blessings be upon him) running between the (middle flat part) of Safa and Marwah, and he was saying: "The valley of Abtah should not be crossed except by running."