You need to read that link bro. Its one of the first things he discusses...
"Amentoflavone possesses the highly unique ability to increase calcium release; in fact, essentially only one other commonly found compound shares this mechanism: caffeine. Unlike caffeine though, Amentoflavone is 20 times more potent at increasing muscle calcium than caffeine [1]. This increase in muscular calcium concentration is part of the reason why caffeine is an ergogen (capable of improving exercise performance), and Amentoflavone achieves this effect in a more potent manner."