What is "functional training"?

In the early 2000s, CrossFit founder Greg Glassman was perplexed that triathlete Mark Allen was named "fittest man on Earth" by Outside Magazine. "Let’s just assume for a moment that this famous six-time winner of the IronMan Triathlon is the fittest of the fit," he mused, "then what title do we bestow on the decathlete Simon Poelman who also possesses incredible endurance and stamina, yet crushes Mr. Allen in any comparison that includes strength, power, speed, and coordination?"

Glassman decided that if his brand, CrossFit, was going to claim to make people more "fit", he had to first define what fitness actually is. The definition he settled on: "increased work capacity across broad time and modal domains." Someone might be able to squat 600 pounds or do a 500 pound clean & jerk, but can that same person run a quick 400 meter dash and knock out 20 pull-ups? Another athlete might have an exceptional marathon time, but can that same person bench press their bodyweight, or excel at a high-intensity circuit? Fitness, according to Glassman, isn't being a specialist — it's being a skilled generalist.

Glassman went on to define his brand, CrossFit — a training system designed to produced skilled generalists rather than specialized athletes — as "constantly varied functional movements performed at relatively high intensity." But there's an elephant in the room here: what is a "functional movement"?

The overhead squat vs. the front raise: which is more functional?

There are generally a few different, and all relatively vague, definitions of "functional" that I've seen get bandied about by fitness gurus:

  • Skill transfer to daily living
  • Requiring core activation
  • Requiring balance and stabilization

All these definitions are completely, totally wrong. To see why, we can just compare two movements: the overhead barbell squat, and the one-arm dumbbell front raise.

Let's take the first definition. It may be true that squatting is an important movement for daily activities. But it's not likely that many of us find ourselves needing to squat to parallel or below while awkwardly holding something overhead; conversely, it's highly likely that we find ourselves raising our hands forward relatively frequently.

Overhead squats do require quite a bit of core activation. But so do front raises! In order to hold a heavy weight at an arm's length away from our bodies, we need core activation to prevent the spine from flexing.

The requirement of balance and stabilization is vague. If I do a front raise standing on one leg, it requires balance and stabilization. I can do it while standing on a BOSU ball. Does that make it more "functional"?

Therapy or fitness?

The problem with all the above definitions is that they're approaching functional training from a perspective used in the medical field — specifically physical and occupational therapy. That's where the idea of transfer to daily activity comes from. An occupational therapist, for example, may work with a stroke victim on basic skills like reaching and grabbing, brushing their teeth, or using the restroom.

But functional training is not rehabilitation; it's fitness. Accordingly, we have to view the concept of functionality from a different perspective.

"Functional" in therapy = broad transfer across everyday activities
"Functional" in fitness = broad transfer across exercise modalities

When we define functionality from this perspective of fitness, we can immediately see why we view overhead squats as being more functional than front raises. Front squats are a deltoid isolation exercise with little transfer to other exercise modalities — even shoulder-dominant movements like overhead pressing, because those movements require multiple muscle groups activating synergistically. Overhead squats develop hip and shoulder mobility; they demand intense core activation; and they develop strength in the quadriceps, glutes, hamstrings, spinal erectors, shoulder complex, triceps, forearms, and much more. Moreover, this kind of whole-body activation is extremely demanding. Develop a strong overhead squat and you'll improve strength and stamina across a variety of other exercise modalities. 

Defining functional movements

Now that we know that functional movements should have broad transfer across exercise modalities, we have to have a clear definition of what makes a movement functional. Functionality exists on a bit of a spectrum, we can make modifications to various exercises to depending on how broad-based we want our programming to be. The criteria are:

  • Multi-joint
  • Multi-plane (frontal, saggital, and transverse planes)
  • Dynamic and stabilizing elements

Let's take a basic seated military press. This exercise is multi-joint, but the seat does most of the stability work and it's only in one plane of motion (frontal). We can increase the movement's functionality simply by standing; now the movement has both a dynamic element (pressing) and a stabilizing element (trunk stability). To make the movement even more functional, we could do a few different things. We could add more joints — like a thruster or heavy push-press. Or, we could add another plane of motion — the saggital plane by integrating a hang or power clean, or the transverse by using dumbbells and rotating during the press. Heck, integrate a squat as well, and you've got a highly functional fitness movement.

Functional movements in programming

So why don't we just do complex movements like twisting dumbbell thrusters? Because in the context of a training program, we need a certain degree of specificity. We need to develop a strong squat, and the best way to do that is with simple, heavy squatting. We need to develop strong core stabilization, and that means front and overhead squatting, and plenty heavy deadlifts. We even need some degree of bodybuilding-style isolation exercises, because few of us are gifted enough not to have any asymmetries or weaknesses in our kinetic chain. 

We want the core of our training program to be multi-joint functional movements — squatting, deadlifting, standing presses, kettlebell swings/cleans/snatches, rowing, pull-ups, and chest pressing. Going multi-plane requires a corresponding drop-off in applied intensity to any specific domain. A great analogy here is a garden hose — imagine our neurological and metabolic energy pathways are like water pressure in a garden hose. We can focus all the 'water pressure' on one thing, like doing a single-joint isolation exercise (leg extensions, biceps curls), but this is time consuming and inefficient. Instead, we can poke holes in the garden hose and distribute the water pressure more widely. To a point, this is more efficient and helps us train for broader fitness goals. But poke too many holes in the garden hose, and nothing really gets enough water. Likewise, if we use overcomplicated movements in the pursuit of maximum 'functionality', we may not provide an adequate stimulus for any one specific domain. A functionally-focused training program must balance a number of variables for total fitness development. 

How do we optimally integrate functional movements into our training? It's an art as much as it is a science, and it depends on your goals and the time you have to devote to the gym. Check out our recent post on training for General Physical Preparedness for more.