Musnad Ahmad 27:544

Yazid narrated to us, from Hajjaj, from Abd al-Malik ibn al-Mughirah al-Ta’ifi, from Abdullah ibn al-Miqdam, who said: I saw Ibn Umar walking between al-Safa and al-Marwah, so I said to him: "O Abu Abd al-Rahman, why do you not perform *ramal* (brisk walking)?" He said: "The Messenger of Allah, peace and blessings of Allah be upon him, performed *ramal* and then ceased."