Transcript:
Caulfield: A "brick" workout? Frazz: It stands for "bike-run-something-something." Caulfield: You should call it a "burito": Bike und run in that order. Frazz: That's a stretch. Caulfield: Said the guy who thinks "ick" stands for "something-something."
According to my extensive* research, it can be “Bike Run In Combination”, or like two bricks stacked on top of each other, making something stronger, or maybe because it’s how your legs feel afterwards (or even maybe named for “Matt Brick”).*really just a google search.