The Messenger of Allah ﷺ would prostrate, then sleep and breathe audibly, then rise and pray without performing ablution.I said to him, "You prayed without performing ablution, even though you had slept?"He replied, "Ablution is only required upon one who sleeps lying down."Uthman and Hannad added, "For when a person lies down, his joints relax."
حدثنا يحيى بن معين وهناد بن السري وعثمان بن أبي شيبة عن عبد السلام بن حرب وهذا لفظ حديث يحيى عن أبي خالد الدالاني عن قتادة عن أبي العالية
أن رسول الله ﷺ كان يسجد وينام وينفخ ثم يقوم فيصلي ولا يتوضأ قال فقلت له صليت ولم تتوضأ وقد نمت فقال إنما الوضوء على من نام مضطجعا زاد عثمان وهناد فإنه إذا اضطجع استرخت مفاصله
[Its chain of transmission is daif]. Tirmidhi narrated it in the book of Purification, chapter "What Has Been Said Regarding wudu after Sleep," no. 77, from Hannad, with this wording. Daraqutni said in 1/159, 160, "Abu Khalid alone narrated it from Qatada, and it is not sound." Abu Khalid al-Dalani was known to conceal his sources, and here he narrated using vague transmission wording.