I think people get married to ideas, methodologies, and exercises. I'll lump myself into that group as well. I'll admit that I've known of the benefits of unilateral training for a while yet never implemented it. Until I started getting hurt, I hit plateaus, and honestly felt like I was working for nothing.
Now, I'm not necessarily a competitive weightlifter. It's just something I am passionate about because I find beauty in working against the natural forces of the earth. I am by no means elite. So when I ended up in physical therapy for knee pain, and was told my hips and back were all out of wack, I knew I needed some changes. I was advised to do more unilateral work, particularly in the squatting and hinging movement patterns. Not having anything to lose, I decided to take it a step further and do all of my strength movements as unilateral exercises (one leg, or one arm).
Now, squatting and pulling are two very common staples in weightlifting programming, as well as for athletes in general. I myself was doing them 5-6 days per week for the past 3 years prior to trying this experiment. They are highly effective movements for maximal strength gains. Unless some things are out of wack, then there is definitely a possibility for plateau and lack of progress. But what would it look like for a weightlifter to not squat on both legs, and not deadlift on both legs?
Thus, I decided to embark on a training program that would only consist of unilateral strength movements. I also decided to use the opportunity to document the process on YouTube, in a small effort to learn video editing. Before I began, I set a few ground rules regarding the Olympic Lifts, and then stopped squatting and deadlifting.
What I noticed, over 14 weeks of not doing any traditional squats (save for standing up from snatches and cleans), is that my bilateral strength went nowhere. My squat maxes stayed the same, my deadlift stayed the same, my shoulder press stayed the same, literally, I did not get stronger. What did happen, was that I got faster. While I have no way to show this from a data collection standpoint, it was clearly visible when comparing lifts side by side, as well as by feel. Part of this is likely due to the increased quality of muscle contractions that were happening as my nervous system started "talking" to my muscles more efficiently, and also partly due to having some extra muscle and general body weight behind those lifts.
I noticed that it was easier to get more work in during a shorter time frame, likely due to not needing as many warmup sets to build up to working sets. Before, a normal session would take up to 2.5 hours, whereas the unilateral session took roughly 60-90 minutes. I was able to move weight, in higher volumes, in shorter times, which freed up the ability to do more of my actual job of coaching.
It was also mentally refreshing to not have to get under as heavy loads day in and day out. When trying to lift maximal weights, often times you have to spend a lot of time under heavy weights, which can mentally a drag. Doing only single leg work was challenging, but refreshing to not have to put double your bodyweight on your back.
In thinking about how it can be applied to athletes, I realize more now that squatting on both legs may not be the best for everyone. Especially with most sports being played on one leg at time (sprinting, kicking, changing directions, etc), having time spent under load on one leg can be highly beneficial in both increasing strength, explosiveness, and injury resistance. While learning how to squat bilaterally is important as a foundational movement, it may not be the most appropriate at every time of a training cycle or season. Simplicity is also a factor, as teaching regular squatting movements can be difficult but teaching a split squat is a little easier to understand for the most part.
In looking back, I also realized that I'd not really suggest single leg deadlifts for most people (Single Leg RDLs are fine), but would opt for different common stances (sumo versus conventional). I also would opt for more single leg extension chain movements (back extensions, reverse hyper-extensions, and single leg hip thrusts), instead of doing single leg deadlifts or possibly RDLs. The RDL thing is one I'm iffy on, because I know many athletes benefit from them, I just don't get much out of single leg RDLs.
These are just a few of the plethora of lessons I learned about not squatting on both legs. I will be experimenting more with these concepts in the weeks to come, and implementing them alongside traditional bilateral squatting and pulling movements to get a better understanding of a holistic approach. But for now, these are the major key lessons I learned and what I found to be effective after 3 months of taking off of a movement I'd done nearly everyday for 3 years.