In the Amida, one may only BOW where the Hakhamim legislated where one should bow- in the 1st and 18th Berakha of the Amida.
In the 1st Berakha (ברכת אבות, Blessing of the Forefathers), one bows at the beginning of the Berakha [ברוך אתה יי] and at the end of the Berakha [ברוך אתה יי מגן אברהם].
In the 18th Berakha (ברכת הודאה, Blessing of Thanks), one bows at the beginning of the Berakha [מודים אנחנו לך] and at the end of the Berakha [ברוך אתה יי הטוב שמך ולך נאה להודות].
If one bows in the beginning or end of other Berakhot of the Amida, we teach that person not do so. Additionally, one should not bow in other places in the prayers, like at ולך לבדך אנחנו מודים in ויברך דויד, since the Hakhamim did not legislate that one should bow there.
(See Shulhan Arukh Orah Hayyim Siman 113 [סימן קיג])
In the 1st Berakha (ברכת אבות, Blessing of the Forefathers), one bows at the beginning of the Berakha [ברוך אתה יי] and at the end of the Berakha [ברוך אתה יי מגן אברהם].
In the 18th Berakha (ברכת הודאה, Blessing of Thanks), one bows at the beginning of the Berakha [מודים אנחנו לך] and at the end of the Berakha [ברוך אתה יי הטוב שמך ולך נאה להודות].
If one bows in the beginning or end of other Berakhot of the Amida, we teach that person not do so. Additionally, one should not bow in other places in the prayers, like at ולך לבדך אנחנו מודים in ויברך דויד, since the Hakhamim did not legislate that one should bow there.
(See Shulhan Arukh Orah Hayyim Siman 113 [סימן קיג])