Ebrahim bin Muhammad says:
"When 'Ali Radiyallahu 'Anhu described Rasulullah Sallallahu 'Alayhi Wasallam, he used to say: Rasulullah Sallallahu 'Alayhi Wasallam walked, he lifted his leg with vigour. He did not drag his feet on the ground like women do. When he walked, because of the speed and force of the legs, it seemed as if he was descending from a high place"
حَدَّثَنَا عَلِيُّ بْنُ حُجْرٍ، وَغَيْرُ وَاحِدٍ، قَالُوا‏:‏ حَدَّثَنَا عِيسَى بْنُ يُونُسَ، عَنْ عُمَرَ بْنِ عَبْدِ اللهِ مَوْلَى غُفْرَةَ، قَالَ‏:‏ أَخْبَرَنِي إِبْرَاهِيمُ بْنُ مُحَمَّدٍ مِنْ وَلَدِ عَلِيِّ بْنِ أَبِي طَالِبٍ، قَالَ‏:‏ كَانَ عَلِيٌّ إِذَا وَصَفَ النَّبِيَّ صلى الله عليه وسلم، قَالَ‏:‏ كَانَ إِذَا مَشَى تَقَلَّعَ كَأَنَّمَا يَنْحَطُّ مِنْ صَبَبٍ‏.‏
English reference : Book 18, Hadith 117
Arabic reference : Book 19, Hadith 124