What i had in mind actually is to use it during PCT to prevent muscles loss
Don't let creative advertising decieve you. Anabolic simply means shifting metabolism towards synthetic pathways. Its association by the bodybuilding community with the word steroid and subsequent massive gains makes it a great marketing device.
Eating a hypercaloric diet is anabolic.
I haven't read their marketing, but their spin likely involves research that shows leucine works at a molecular level to increase protein synthesis by two pathways: direct stimulation of mTOR and stimulation of something called p70S6k. What they don't tell you is the most recent research shows this to be a fatiguable effect, wherein not enough is detrimintal but an excess likely has little effect beyond those associated with additional calories. It is also associated with TRANSIENT increases in the post exercise window (a time when prot. synth is already very low so doubling it still doesn't do a lot). High physiologic insulin and exercise are also very impt.
You have to realize most of this research doesn't have bodybuilders in mind. Its to benefit the extremely ill populations who are catabolic and have a net negative nitrogen balance due to pathologic conditions.