Last week I was listening to a podcast, per usual, on my way to work when I heard something that made me rewind and think deep and hard about a very basic and foundational exercise: the squat. Mike Boyle brought up a concept that I have not heard of before: bilateral deficit. In essence, he gave a great example of using a vertical jump. If your vertical jump was 30 inches jumping off both legs, one would hypothesize that jumping off your right leg + jumping off your left leg should equal 30 inches. Each should be about 15 inches. What he and others have found is this is not the case. Most people will have a higher (right leg + leg left) single leg vertical jump total compared to jumping off two legs. Why is this the case?
The case of bilateral deficit exists as our neurological system isn’t wired to jump off both legs at once. We do most things on one leg in sports, allowing our nervous system to be on cue and help us realize our athletic potential. What does this have to do with squatting? I have always thought bilateral (two legs) back squats were a staple of all strength and conditioning programs for sports. However, after listening to Mike’s rationales and evidence of success with unilateral (single leg) exercises, I have realized this form of squatting is not optimal for improving performance and decreasing the risk of injury. In most sports, the ability to transfer force and control motion of one leg on the ground is a greater skill to have than producing force through both legs at once. Combined this with the massive compressive sports of the bar on the spine with several hundred pounds of weight on someone’s back, and changing to unilateral exercises seems like an obvious improvement in my training and helping others with their training.
Yes, squatting is a great technique to learn as a person and an athlete. I am obviously not telling you to never squat again. But I do find a lot of value in reducing or eliminating front and back barbell squat for most people. There are plenty of other ways to work the squat pattern with dumbbells, bands and kettlebells in various positions: split leg squat, elevated rear heel squat, jump squats, goblet squats. I try to teach best practice to people and this is the best I know about squatting right now. If something in the future comes up, I may or may not change my opinion on back squats. For now, they can take a back burner to other exercises that provide the same if not better results.