Is the BFR Really the Cause of the Muscle Growth?

The BFR works through more muscle fiber recruitment and not through the metabolites itself. You're just basically pre fatiguing a muscle to maximize muscle fiber recruitment at a much lower load. There's usually no difference in a muscle growth between the two conditions. So, so whether you do 20 reps to failure or you do BFR and you just do 10 reps, um, the end result is the same.