When the Prophet (May peace be upon him) wanted to eat or sleep, he would perform ablution. She meant that (the prophet did so) when he was sexually defiled. (Using translation from Abū Dāʾūd 224)
«كَانَ رَسُولُ اللهِ ﷺ إِذَا أَرَادَ أَنْ يَأْكُلَ أَوْ يَنَامَ وَهُوَ جُنُبٌ تَوَضَّأَ»