We got Brian Johnson -- the influencer behind the internet personality -- out on Rodeo Dr. Saturday, where the dude was shirtless (per usual) and about to start pumping iron in front of everybody ... which he promptly did, right in the middle of traffic. Dead lifts, baby!

After a few reps, we invited TLK to come chat with our Celebrity Tour patrons ... and he did. Before hopping on, though, we asked him some hard questions -- like why he lied about not being on the stuff for years, and why folks should believe anything he says now.

He's got answers for all that, basically saying ... look, believe me or don't -- but my workout regimen and supplement program will get ya jacked and feeling great. That's basically his message.

Then, a bombshell ... Liver King admits he's still on 'roids!!! When we ask why -- especially since it's caused him so much reputational damage -- he says he has to ween off it, and that he can't just cut it out cold turkey.

If you're unfamiliar with this whole saga ... Brian recently copped to being on steroids, this after years of denying it and insisting that his program was the only thing giving him results on his physique.