It is reported about Ibrahim al-Nakha'i that he would stand on bardi and prostrate on the ground. The narrator says: We asked: What is meant by the word bardi? He replied: A mat.
Tabarani recorded it in al-Mu'jam al-Kabir, and its chain is hasan (good).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2273