Article Review: Build Bigger Legs, One at a Time

T-Muscle just published an article by Mike Boyle called Build Bigger Legs, One at a Time.

The article covers an experiment Mike Boyle did with some of his athletes - instead of using heavy, low-rep bilateral leg training, he used heavy, low-rep unilateral leg training. Specifically, he swapped out his usual front squats for Bulgarian split squats, which he refers to as Rear Foot Elevated Split Squats (RFESS).

Before you read the rest of this post, please read his article. It's interesting, brief, and showed some real utility to low-rep Bulgarian Split Squats.

I do have some issues with his experiment methodology. The Bulgarian Split Squat is a unilateral exercise, but if you want to, it's pretty easy to cheat a bit by pushing with your back foot as well. The majority of the load is one the front leg but the back leg can assist, not just keep balance.

Another is that he's comparing the BSS with the back squat...but doesn't back squat his athletes anyway. He front squats them, and they gave them 15% on their best front squat and called it a back squat 1RM. That's a bit iffy. I think it would have been much better if he'd compared two lifts they actually do, not an estimated lift on an exercise they don't perform.

He also didn't address what's known as the bilateral deficit - generally, you can lift a little bit more with unilateral versions of an exercise than bilateral ones. You can one-arm standing press a heavier dumbbell than if you used two and did two-arm standing presses, for example, or curl two dumbbells instead of one. There is a whole complicated explanation for this I don't fully understand myself, but it's real and it's there. It's why my 8-rep reverse barbell lunge is so high compared to even my 5-rep max back squat, despite using 1/2 of the legs. It's more than 1/2 of my back squat.

Finally, he didn't test their front squat again, he just tested how much they increased their BSS using low-reps and half of their estimated one-rep max. As it says in the article:
"After approximately six weeks of RFESS, we did a simple repetition-max test. Each guy took 50% of his one-rep max on the back squat and did as many RFESS reps as possible with each leg. Since we don't do back squats in our program, we had to estimate each guy's max by adding 15% to his 1RM in the front squat. And then, as I said, we used 50% of that number."

It's still an impressive jump in strength and in loading. But I think it would have been well served by a test of their Front Squat before the test and their maximum reps in the BSS at 1/2 of that number, and then do the same at the end. We'd know how much they were able to front squat and how many times they could BSS half of that weight. Right now, we only know where they ended up, and it's not clear how much carry over there was to the front squat. Not that improving their front squat was the goal, I understand that, but still, it would have demonstrated the utility of unilateral (one-leg) strength training for boosting bilateral (two-leg) strength.

My criticisms aside, it's a valuable read and an interesting experiment in improving leg strength. I'd like to see someone take it a step further and try it with pre- and post-exercise testing of a "control" exercise (front or back squat) and the trained exercise (to see where they start for a max-reps set of 1/2 the control exercise loading).