When the Prophet (may the peace and blessings of Allah be upon him) used to raise his body from rukoo', he would straighten his back until all of the joints of his body settled in their place.
Abū Mas'ood Al-Anṣārī (may Allah be pleased with him), when he described the prayer of the Prophet (may the peace and blessings of Allah be upon him) said:
"Then [the Prophet] said: sami‛-Allaahu li-man ḥamidah, and he rose up standing, until all of his joints settled in their place..." [Abū Dāwood: 863]
When rising from the bowing position, the Prophet (may the peace and blessings of Allah be upon him) would raise his hands to either shoulder or ear level and say:
Transliteration: "Sami‛-Allaahu liman ḥamidah"
Translation: "Allah listens to him who praises Him."
[al-Bukhārī: 689, Abū Dāwood: 863]
Further to this supplication, he would say:
Transliteration: "Rabbana wa lakal ḥamd"
Translation: Our Lord, to You belongs all praise.
Another extended version of this du'aa is:
Transliteration: "rabbanaa lakal-ḥamdu ḥamd-an katheer-an ṭayyib-an mubaarak-an feeh"
Translation: Our Lord, to You belongs all praise, an abundant beautiful blessed praise.
Note that if a person is praying behind an imām, they should not say Sami‛-Allaahu liman ḥamidah, but rather they should respond when the person leading the prayer says it, by saying: Rabbana wa lakal ḥamd. As for the person leading the prayer, or the person praying alone, they say both supplications.