I observed the Prophet ﷺ in his prayer, and he would remain settled in his bowing and prostration for the length of time it takes to say, "Glory be to Allah and praise be to Him," three times.
حدثنا مسدد حدثنا خالد بن عبد الله حدثنا سعيد الجريري
رمقت النبي ﷺ في صلاته فكان يتمكن في ركوعه وسجوده قدر ما يقول سبحان الله وبحمده ثلاثا