See the ROSH (Berachos 5:3) who gives two explanations to how Rebbi Akiva could have moved during his Tefilah, in light of the Gemara which states that it is prohibited to bow down except at the prescribed places. The first answer is that he bowed down many times during his Shemoneh Esreh before reaching the closing blessing of each passage, which is permissible. The second is that he bowed many times during his personal, private supplications that he recited after completing the blessings of the Shemoneh Esreh. In either case, the vigor of his prostrations caused his body to move. (See also MA'ADANEI YOM TOV to the Rosh, #3, who quotes the TALMIDEI RABEINU YONAH who point out that "Hishtachava'ah" constitutes prostration while outstretching one's hands and feet completely on the ground. Bowing in such a manner and then rising perforce results in rising in a slightly different position that one started.)

Y. Shaw

D.A.F.

Jerusalem, Israel