Killsession Musings: Unilateral vs Bilateral Leg Training.

When I first started training, as so many young guys do, I read the muscle mags, I did exactly the kind of training that was in there. Bilateral movements, machines, isolation, steady state cardio, were commonplace in my workout routines for years. Then I started reading from different sources, from strength coaches such as Michael Boyle, Alwyn Cosgrove, Eric Cressey and Gray Cook, I started to learn there are more efficient, productive and healthier ways to get the physical dimensions I desired. Now, having said that, I did do what Cosgrove calls "an over-reaction in the short term, an under-reaction in the long term" with these ideas, I dropped most bilateral movements, all machines, all isolation and all steady state. As Nate Miyaki states:

Most strength trainers, or anyone who's ever taken a physiology class, have heard the ol' sprinter vs. marathon runner comparison a thousand times. You know the drill. Marathon runners that engage in primarily low intensity, aerobic activity are usually skinny-fat, jiggle when they wiggle, and are so injured and beat-up that they look like they've come straight out of a Resident Evil movie. Sprinters that engage in primarily high intensity, anaerobic work are generally more lean and muscular.
It's amazing to me how many intelligent people understand this on a conceptual level, but don't practically apply it within their training protocols. "Yeah, marathon runners are losers." Then that same allegedly intelligent person will go out and do cardio three times a day to try and reach low single-digit body fat percentages.
No physique athlete has any business spending two hours on a stationary bike (emphasis added), unless there's a hot chick with a nice ass on the elliptical machine sweating in front of you. And even then, either man-up and make your move or go home and cry to your buddies about what could have been, but don't waste your time on a glorified coat rack.
The fittest "looking" people in the world, and the smartest coaches in the world -- the Testosterone crew, bodybuilders, figure girls, fitness models, etc. -- base their exercise programs around strength training. They all lift weights -- both the men and the women. Cardio may be a part of the plan, but it's not the foundation. Christian Thibaudeau didn't become The Beast (as an athlete or coach) on an elliptical machine. (emphasis added)

And on a side note, I would say most physique athletes do cardio out of tradition rather than necessity. Diet and strength training are what changes physical appearance. Cardio is supplemental at its very best. (Miyaki 2010)

That was about a year ago, since then I have tried playing around with what fits where and have largely discovered through my own training and my clients that the only thing I would fit back in are bilateral movements (2 legged). I like the conventional deadlift, sumo deadlift and the front squat, that's about it. When programming for my clients it's my responsibility to provide them with the best possible care I can, most of my clients come in tackling weight, strength, body fat and image issues, what they generally don't realise is that they are also dealing with flexibility, mobility and stability issues too.

It's my job when designing programs to tackle all of these issues, how do I best go about doing this? By designing programs that hit several birds with one stone and how do I do that? Largely by putting unilateral leg movements (single leg), all free weights, resistance as opposed to movements based training for the abs, HIIT over steady state and other functional exercises together that compile a "functional" program. What is meant by this buzz word "functional"? In this case it means a program that will help increase dynamic strength, drop body fat, increase stability and mobility (where applicable and possible) and most importantly do no harm! As Michael Boyle states:

[Gray]Cook's analysis of the body was a straightforward one. In his mind, the body is just a stack of joints. Each joint or series of joints has a specific function and is prone to specific, predictable levels of dysfunction. As a result, each joint has specific training needs. The table below looks at the body on a joint-by-joint basis from the bottom up:

Joint Primary Training Needs
Ankle mobility (particularly sagittal)
Knee stability
Hip mobility (multi-planar)
Lumbar Spine stability
T-Spine mobility
Gleno-humeral stability (emphasis added)

The first thing you should notice as you read the above table is the joints simply alternate between the need for mobility and stability as we move up the chain. The ankle needs increased mobility, and the knee needs increased stability.
As we move up the body, it becomes apparent that the hip needs mobility. And so the process goes up the chain: a simple, alternating series of joints.
You're probably asking yourself, "What does this have to do with lifting?" Can it make me squat more? Yes, absolutely.
The basic fact is that over the past twenty years the average gym-goer has progressed from the bodybuilding approach of training by body part to a potentially more intelligent approach of training by movement pattern.(emphasis added)

In fact, in the sports world, the phrase "movements not muscles," has almost become an overused one and, frankly, that's progress. I think most good lifters have given up on the old chest-shoulder-triceps muscle mag thought process and moved forward to a push-pull-anterior chain- posterior chain thought process. (Boyle 2007)

Unilateral leg training is great for a plethora of reasons, for beginners simple split squats and walking lunges can help with proprioception, balance, glute activation and firing, reduce axial loading (spinal loading) and activate the core musculature while not putting too much awkward load on the person. In most cases a beginner can get away with less than 8kgs in each hand and still be very sore the next day, while similarly the strength gains are very practical and help the client to build a functional base level of strength, that we might progress to more traditional bilateral lifts.

The Split Squat

I have read some stuff that suggests bilateral before unilateral, which I would agree with in principle, but when you're working with a client for 30 mins to 1hr a week, you don't always have the time to work in the flexibility mobility training that is required for bilateral work. This way you can get them training right off the bat as you work on their length issues over the coming weeks. I would, however recommend a largely body weight approach to the first few sessions, due to the sheer volume of reps and the fact that single leg training is difficult enough as it is. There should be progressions from body weight split squats to body weight walking lunges, then weighted versions of both before moving onto the bulgarian split squat and the pistol squat.

The Bulgarian Split Squat

I think it is possible to build muscle efficiently with a either/or approach to bilateral/unilateral training, that being the case I'll go for single leg training for my clients, with some bilateral interspersed, in most cases. Single leg when extrapolated to the other leg actually ends up having you lift heavier loads with less physical stress and a greater metabolic demand which is great for clients.