It is reported that also an activation of the estrogen receptors (ER) results in muscle hypertrophy. More specifically, investigations could identify the ER-β as target for mediating this effect. ... Some phytoestrogens such as ecdysterone and daidzein showed strong selectivity towards the ER-β, which even exceeds the selectivity of S-equol. However, a considerably lower activity of the phytoestrogens is seen in comparison to estradiol or the synthetic ER-β agonists mentioned above.
