Greater than the Sum of Your Parts

Greater than the Sum of Your Parts

Last fall, Boston Dynamics posted a video of its bipedal robot, Atlas, performing a gymnastics routine, complete with somersaults, handstands, and a spinning jump. Just a few short years ago, DARPA held a robotics challenge in which teams were given complex tasks that their robots would have to complete semi-autonomously. Some of these complex tasks included getting out of a vehicle, climbing stairs, and crossing uneven terrain without falling down—things people can do with ease but which require extraordinary feats of engineering and programming for a robotics team. In the DARPA challenge, bipedal robots didn’t fare very well in many of the tasks that require balance. That’s because, as one scientist put it, “walking is not a form of artificial intelligence, it’s rigorous algorithms for how to not fall down.” Yet, today there are bipedal robots doing parkour and Crossfit. Those of us who grew up with the only two Terminator movies that count cannot help but wonder how long before one of these robots is asking for “your clothes, your boots, and your motorcycle.”

Attempts to develop bipedal anthropomorphic robots suggest that the human design is either terribly unstable or amazingly complex—probably both. The problem is that our bodies are not simply a system of levers, joints, and pulleys. Reducing complex human locomotion to coordinated movement about joints will, almost invariably, result in a fall when the attempt involves the meticulous programming of every detailed movement of each joint or lever. People are similar, lab studies have observed that the more a person tries to consciously control his or her balance, the more difficult it is to do so. Balance and smooth human movement involve subtle and subconscious micro-adjustments. We are a mechanical system, guided by intent, controlled by control mechanisms like the CNS, and refined by our experiences. And much of the control and refinement happens without our conscious minds interfering with the process.

We can break complex movements down into a collection of flexion, extension, ab- and adduction, and rotation around our joints, identify the muscles doing the pulling, and even measure the sequence of muscle activation for a given movement. But even with mountains of data about what happens to create complex movement, we can be unable to recreate fluid movement either in automatons or in our own persons. Not unlike taking apart a radio or remote-controlled car when you were a kid, the ability to reduce complex systems to their most basic components does not presuppose the ability to recreate the system from scratch. Coordinated, multi-joint movement is complex.

As an example, consider the functions of a muscle or muscle group. In voluntary, single-joint movements, skeletal muscles have two basic functions: The agonist, or prime movers, are those that accomplish the goal of the movement. For a bicep curl, the agonists are muscles that flex the elbow and curl your hand toward your shoulder. A muscle may also act as an antagonist, opposing the prime movers (agonist). Antagonists decelerate movement about the joint, working in tandem with agonist muscles or groups. If the joint is a hinge joint like the elbow or knee, understanding the roles of the involved muscle groups is simple. 

When we examine big, multi-joint movements—the big barbell lifts, for example—it may be tempting to extrapolate the simple single-joint/agonist-antagonist model to the many joints involved in the lifts. Your agonist joint extensors resist the weight on the way down, then contract concentrically on the way up. Their antagonist pairs act to stabilize and slow the concentric contraction at the top to return you to a standing position. If single-joint models held for complex movements, we could prescribe strength lifts based on the body parts they train and would assign value to each lift as a “leg,” “hip,” “arm,” or “glute” exercise. This is, however, far too simplistic.

Complex movements introduce a host of additional muscle functions and the organizing power of the CNS. Your muscles become joint stabilizers. They reposition joints to drive internal and external forces to different parts of the body. Built-in sensory receptors act as motion sensors, affecting your proprioception and your reactions to changes in your environment, stability, and balance. And, most of this happens without you thinking about it.

Simplifying complex lifts to training body parts undermines the difficulty of their execution, the necessary learning that goes into their improvement, and the value we should place on training them. The big barbell movements do not merely train muscles; they train movement, control, coordination, and whole-body force production. If you spent twice as much time at the gym, targeting specific muscle groups with single-joint exercises, you wouldn’t get a fraction of the benefit that comes from barbell training.

When it comes to human motor control, understanding the jobs of your joints, bones, and muscles and knowing the model or goal for a particular complex movement does not mean you will be able to either perform or teach the movement—let alone do so with grace, accuracy, or precision. For now, we have a leg up on our potential bipedal robot overlords because our systems are designed for this kind of stable instability. It is what gives us the ability to perform a wider variety of complex tasks than any other animal on the planet. Still, however, in lifting and other athletics, when we set our sights on repeated, skilled movements, it helps to understand the complex goings-on and consider what else might be getting a workout when you constantly challenge yourself to lift heavy things and not fall down.

Moving with Precision

Precise movements comprise mostly unconscious efforts in which the body executes exactly the intent of the mind. Even with that mouthful of a sentence, this is much more easily said than done. Try, for example, throwing a dart, learning a new dance, or yoga for the first time. Or, simply recall the first time you attempted to put a bar and your back, squat down, and stand up. Despite reams of pages on muscle function and movement theory and endless YouTube videos, only the rarest, highly gifted athletes will come close to picking up a complex movement from reference material on their first try. You might approximate the task, but not mimic it exactly. 

Precise movements require the coordinated execution of many muscular contractions to produce one harmonious movement, accomplishing a particular goal with exactitude and repeatability. Some complex tasks require versatility—walking down an uneven sidewalk, skiing downhill, fighting; others require the execution of practiced movements—lifting, throwing sports, anything involving accuracy. But all high-level movements require precision. This holds true even if, for you, a high-level movement means not falling down in the shower or safely climb the stairs in your house. 

For every complex movement, you have a goal made up of your intent and the understanding of how the movement should go. Your goal is informed by your experience, familiarity and learned responses informing the black box of movement that so often stumps robotics engineers. The final execution of the movement depends on your physical capacity to perform with many systems working together and many possible weak links in the kinetic chain. All three of these pieces—goal, familiarity, and execution—get you from Point A to Point B.

Building Your Goal: Embracing the Imprecision of Learning

You cannot consistently enact your intent without being familiar with the coordinated execution involved in a given movement. Put in lifter’s terms: You can squat heavy if you’ve never squatted. For coaches, experience under the bar is a crucial requirement for effective teaching. A coach cannot teach someone how to squat if the coach is unfamiliar with the model and movement of the squat. And this absolutely cannot be learned by reading a book, watching videos, or through “coaching reps.” Going back to the reductionist problem, you can know all the pieces involved and still have no clue how the whole thing works.

As a lifter, coordinated execution takes practice. The “model” for how to squat, bench, press, or deadlift (or how to perform any complex movement) exists in your head and nowhere else. You can build or inform this model with knowledge—reading books and articles, learning anatomy, watching people squat. Once you put a weight on the bar and try to move it, however, your body organizes its resources to approximate some internally held ideal. If your perception of how the correct movement should feel is uninformed, then efficient or “correct” movement will be haphazard at best. Instead, you have to learn how to execute a movement by performing it; practice develops your internally held model.  

Deliberate practice involves more than doing the same thing over and over again. If you are going to develop your internally held model for a complex movement, you have to practice with that aim in mind. Knowledge of what the correct movement should look at feel like is preeminent. Then you need to build in a feedback loop into your training, one that allows you to assess your movement and make changes. Those changes and reassessment will then inform your practice. So, while the best and most fluid complex movements are those that happen with as little conscious thought as possible, the learning process involves both conscious thought and trail and error. Keep this in mind next time you are struggling with now-what-are-my-knees-supposed-to-be-doing thoughts in the middle of a set while learning how to lift. 

To develop both coordination and the repetition of precise movement, you must work through the phase of being imprecise and thoughtful. And, occasionally, you have to revisit it to work on refining your form or fixing form drift. 

Familiarity: Practice Makes You Better

It is with thoughtful action that we build familiarity with a complex movement. Conscious control over certain aspects of your movement makes you less graceful but informs the parts of your brain that lay out a plan of action and react to sensory input. Coaches use things like teaching methods and cues to help you build familiarity with a movement. Teaching informs what the movement should feel like, building your familiarity through practice. A good teaching method will put you in the correct positions, and force your brain to connect those positions to its natural imperatives to not fall down, not get squashed, and definitely do not drop that bar on your head. While you learn the feel of the movement, cues or tasks for each rep give you specific goals to help you develop or refine it. For example, a coach might tell her lifter to focus on bending over in the squat—usually trying to teach the lifter’s subconscious brain that the bar will not decapitate them if they bend over just a little bit more as they start to squat. Or a coach might instruct the lifter to “lift your chest,” “push with your feet,” “throw the bar back,” or “MIDFOOT!!” all reminders that put the lifter’s focus somewhere other than “Deadlift,” “Press,” or “Squat.” 

But your brain will look for shortcuts, and it is a mistake to assume otherwise. We all have movement quirks, like unconscious tics, that reveal how we might lift or move without instruction or practice doing so. As an example, one of the most common lifting quirks is the tendency for a lifter to relax at the bottom of a squat. Everything starts out smoothly and under control, you take a big breath and send your hips back, back, back, even a little more. You are just about parallel, then suddenly you accelerate. At what should be the tightest part of the lift, you speed up; your butt crashes into your calves; and you bounce out of the bottom. You survive and call it a good rep, whereas your coach would have liked you to stop a few inches higher and rebounded off the tightness of your glutes and hamstrings. 

The tendency to get loose at the bottom of the squat is your brain’s desire to get “comfortable,” alleviating the tightness and stress of the movement. The squat, bench, press, and deadlift as we perform them are natural in that they use your joints, muscles, and systems in the ways those things are meant to be used, but they are contrived in that there is a right way and a wrong way of accomplishing the goal of moving the barbell through the range of motion. We have models for each lift that define efficient movement and maximize the training effect of each. If you observe children sitting at the bottom of a squat or people in countries who regularly squat during the day, they will look more like the lifter who is bouncing comfortably (but incorrectly) out of the bottom of his squat and less like the low bar squat model. Familiarizing the control systems of your brain with the correct squat model teaches you to default to the correct movement for lifting, to covet tightness rather than avoid the uncomfortable aspects of the lift. For the lifter who lacks the familiarity of long experience under the barbell, if you are comfortable and if it feels good to you, you’re probably doing something wrong.  

Practice makes…not perfect, but consistent. We may be treated to perfect reps on occasion, but as the weight increases on the bar or as you play your sport, you are more often challenged to react to dynamic changes. Whether your goals involve precise control over your body’s movements or a constantly changing environment, there are a seemingly infinite number of variables that can affect your performance, day-to-day, set-to-set, and rep-to-rep. In those cases, we may be pulled out of our “lifting flow” and forced to react. 

Your reactions are learned responses. You may sense a sudden change in your balance or the bar’s movement forward of your midfoot. In the “oh crap!” reaction of the moment, you may abandon all cues and just try to avoid getting pinned to the floor. Or, with practice, you double down on your form and the experience of the hundreds of reps you’ve practiced so far. Which you do is likely not up to you, but up to your familiarity with which response best suits the moment. In this way, learning how to react helps build your familiarity and complete the loop of coordinated movement:

Thoughtful action leads to precise reactions leads to precise action. 

Execution

Precise movement—”flow,” grace, fluidity, good form—comes from much more than the sum of your individual parts. As lifters, we are training the whole system. And, in this way, we solve the puzzle of the unknown and unknowable. Because, while we may not have practiced all the situations in which strength will be useful, we are generally strong, generally coordinated, and practiced in whole-body force production. This builds a wide base for sports, life, and the challenges of the impending robot apocalypse.