As in the practical "feel it" sense? I consume a type of BCAA or EAA mix pre- and intra-w/o each time. From Purple Wraath to Xtend, I've used them quite a lot. I'm still working on my first tub of AXcell. But in the practical sense, when I'm not using them (days I forget or when I run out temporarily), I can tell a difference. For me, I get a little bit of boost with recovery intra- as well as feel like I have more energy to go on. It's not a stim-type energy, but more fuel for the fire, so to speak. Is there a benefit? I think so. Anything that gets me going better, harder, faster, or more is a benefit in my book.