The Messenger of Allah ﷺ used to pray thirteen units during the night. Most of his prayer was performed standing, but when he grew older and his body became heavy, most of his prayer was performed sitting.He would pray while I lay stretched out before him on the bed where he slept. When he wanted to perform the witr prayer, he would nudge me and I would get up so he could pray witr. Then he would lie down until he heard the call to prayer, then he would rise and perform two brief units of prayer. Then he would lie on his side against the ground, and afterward go out for the prayer.
حدثنا حسن بن موسى قال حدثنا ابن لهيعة قال حدثنا أبو الأسود عن عروة
أن رسول الله ﷺ كان يصلي من الليل ثلاث عشرة سجدة وكان أكثر صلاته قائما فلما كبر وثقل كان أكثر صلاته قاعدا وكان يصلي صلاته وأنا معترضة بين يديه على الفراش الذي يرقد عليه حتى يريد أن يوتر فيغمزني فأقوم فيوتر ثم يضطجع حتى يسمع النداء بالصلاة ثم يقوم فيسجد سجدتين خفيفتين ثم يلصق جنبه الأرض ثم يخرج إلى الصلاة