It is narrated from Hazrat Aisha that the Prophet (peace be upon him) did not use to pray in our "shi'ar". Bishr says that "shi'ar" refers to the garment that is worn on the body underneath the outer garment.
Hadith Referenceمسند احمد / مسند النساء / 24698
Hadith Gradingحکم دارالسلام:حديث صحيح، وهذا إسناد فيه انقطاع