Sheikh Yûsuf al-Qâsim
It is related in Sahîh al-Bukhârî that `Ikrimah said: “I saw a man (praying) near al-Maqâm and say 'Allah Akbar' whenever he moved up or down and whenever he sat or stood up. I told Ibn `Abbâs about it, and he said: 'Was that not the prayer of the Prophet (peace be upon him)?.” [Sahîh al-Bukhârî (1/272).
A similar hadîth is related in Sahîh MuslimSahîh Muslim (1/294)]
There is a clearer narration that `Abd Allah b. Mas`ûd said: “The Prophet (peace be upon him) used to say 'Allah Akbar' in each movement up and down, and in each standing and sitting. So did Abû Bakr and `Umar.”
This is related by al-Nasâ’î (2/205) and al-Tirmidhî (2/33) Then al-Tirmidhî says in his Sunan: “The hadîth of `Abd Allah b. Mas`ûd is an authentic and fine hadîth.”
The Companions of the Prophet (peace be upon him), including Abû Bakr, `Umar, `Uthmân, `Alî and other Predecessors used to practice what is mentioned in this hadîth.
This hadîth shows that it is permissible to say "Allah Akbar" in prayer whenever we go up or down, which includes the prostration in prayer and the prostration of recitation (sujûd al-tilâwah) both inside of prayer and outside of it.
And Allah knows best.
Source: Islam Today