This style of lunge is actually slightly better than the forward lunge when it comes to building muscle, partly because it's harder to compensate with the lower back, so your form is better.
If your goal is to build your quads, this reverse lunging style also beats the forward lunge, which is better for glutes and hamstrings.
Over the last few years it seems that just about every "in the know" performance coach has discussed the conjugate method and why they find it to be the most effective way to train an athlete. By now I think we all know the definition of conjugate or concurrent periodization and how it involves simultaneously trying to raise multiple qualities.