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.
أَنَّ النَّبِيَّ ﷺ كَانَ إِذَا أَرَادَ أَنْ يَأْكُلَ أَوْ يَنَامَ تَوَضَّأَ تَعْنِي وَهُوَ جُنُبٌ