It is narrated from Sayyidah Maymunah (may Allah be pleased with her) that when the Messenger of Allah (peace and blessings be upon him) prostrated, his belly would be raised so high off the ground that if a young goat wanted to pass beneath him, it could have passed.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2705