minhag - Is it permitted to make hand gestures in the Amidah?

Someone told me that I should not move my hands during the Amidah. I found this article in the Jerusalem Post which says:

Indeed, an eerie silence hovers over the issue of outstretched arms during prayer in much of the post-talmudic literature. One notable exception is Rabbi Abraham, son of Maimonides (13th century, Cairo). Advocating a return to original prayer styles, Rabbi Abraham promotes raising the hands when petitioning God.

...

This approach is echoed in later authorities (Rabbi Eliezer Azkari, 16th century, Safed; and others), but does not seem to be the accepted practice. Some halachists suggest that prayer with outstretched arms is the manner of gentile prayer, and therefore should be avoided (Be'er Sheva, 16th-17th centuries, Poland-Italy; and others).

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Modern scholars have demonstrated that a serious issue is at stake here: Christians saw Moses's outstretched arms in the fight against Amalek as a prefiguration of crucifixion.

Codifiers rule that the hands should be clasped over the heart, as a servant stands before a master with awe and respect (B. Shabbat 10a; Maimonides; Shulhan Aruch).

Is it permitted to make hand gestures in the Amidah? Does it matter (a) whether they are with one hand or two (b) whether the hands are raised above the heart or not and (c) in which blessings the hands are moved?