Training: Function and Specificity

As a physical therapist and CHEK practitioner, I recognize that exercise does not train the musculoskeletal system alone – all exercise incorporates the nervous system in some capacity, whether that is through balance and related reflexes, proprioception, or motor control and patterning.  Our human bodies are a composite of intimately connected systems, and, at least where movement is concerned, you cannot isolate systems.  Indeed, when performing standing shoulder presses, a client will be utilizing their shoulder musculature (deltoids and scapular-thoracic muscles) as well as their core (abdomen, glutes, pelvic floor) and ankles (minute balance adjustments).  All of this requires integration of the nervous system (balance, proprioception, coordination of movement patterns and basic firing of muscles units) with the musculo-skeletal system of the shoulder musculature abducting the humerus.


Because of the integration of systems, physical therapists, CHEK practitioners, and other movement and exercise professionals speak often of functional training.  Functional training can be examined from several angles.  Most simply, if an exercise or movement meets a client’s goals, it IS functional, that is, it is meeting a goal, function, or need.  Functional training can also refer to utilizing and replicating tasks or movements necessary for a sport or profession, such as work conditioning to return a client to work after an injury.ex. 1,2  Functional training can also refer to exercise directed at the general public that utilize movement patterns needed for daily life, such as squats, twists, bends (ex. Primal Pattern® Movements, CHEK Institute3).


Indeed, much of the gym equipment at “big box” facilities is not designed to replicate functional movement. Seated elbow flexion on a fixed machine, designed to target biceps, suggests that elbow flexion occurs in a strict plane with a fixed or semi-fixed axis, without incorporating trunk musculature,  other elbow flexors (like brachialis or brachioradialis), or a variety of elbow positions in relation to the trunk. Fixed axis machines can be helpful in rehabilitation settings, but these machines can cause muscle imbalances (is the client working synergistic and antagonistic muscles too?) and, possibly impaired integration of core musculature in functional movement.  For instance, when you go to pick up and carry a heavy item, using biceps to draw that item close to your chest, you are also using abdomen and glutes to support the low back and lift your trunk from the bent position. Knocking out biceps curls on a fixed axis machine does integrate trunk, glutes, and other supportive functional musculature.  Rather, you can train dysfunction by training these biceps muscles to move large loads without proper, integrated trunk support.


Muscles don’t operate in isolation, and they shouldn’t be trained as isolated units (except in specific rehabilitative instances).   The central nervous system is known to activate supportive trunk musculature like the transverse abdominis and multifidus BEFORE a load or weight is imposed or a limb is moved.ex. 4,5  Individuals with low back pain often have impaired firing patterns in these supportive trunk muscles.ex. 6,7  While training on fixed machines might not create impaired firing patterns of the core musculature, it certainly is not training those abdominal and back muscles in a way that replicates their function.


Similar reasoning applies to the utilization of squat machines.  Squats are functional movements (ex. used when picking up something heavy from the floor), but when your body is supported by a machine (such as a tracked bar), your supportive core musculature does not have to work as it would if you were completely unsupported.  Further, your balance and related reflexes remain unchallenged (or at the very least, under challenged).   Like other fixed axis machines, supportive machines that replicate functional, primal movements like squats are still best left to rehabilitative environments.


Functional training is related to a concept in exercise science called specificity of training, which acknowledges that if improvement is desired for a specific activity (ex. squat strength), then the best way to gain that improvement is with a program that closely resembles that goal, considering specifics like velocity, joint angle, type of exercise (ex. closed chain or open chain8), weight used, and squat components that is problematic.  For someone that desires to increase squat strength, they will need to train using squats and other exercises as close to a squat as possible, as well as any supportive musculature that is weak.  They would NOT focus on open-chain knee extensions (such as a gym knee extension machine) as these exercises, knee extensions and squats, differ mechanically and neurologicallyex. 9 though similar musculature, the quadriceps, is used.


Recently, I joined a gym in Illinois that offers obstacle course and ninja-warrior type training.  I’ve never watched American Ninja Warrior, so the mimicry of a hit television show wasn’t the appeal (mimicry is not a bad thing, especially if it is encouraging exercise).  Instead, I joined because I had signed up for Tough Mudder and wanted to properly prepare (i.e. specificity of training).   Being able to squat 150lbs with good form or complete a single arm bicep curls of 35lb does not prepare the body in the same was as replicating the actual task I wanted to perform (goal: Tough Mudder).  Specificity of training is related to a concept called transfer of training, or how well training in one task carries over to another.  How well does a bicep curl of 35lb transfer over to performing ninja ring obstacles or laches? Likely not much, as obstacles and ninja-type tasks are much more complex both to the musculo-skeletal and neuromuscular systems.    Many individuals learn this the hard way, as I learned talking to people AFTER they’ve attempted a Spartan race or Tough Mudder without previous obstacle training.  Typical gym workouts just don’t cut (they aren’t functional or specific) it if you want to be your most successful self on the race course.


How functional are your workouts for your current lifestyle, needs, and goals?  Do you specifically incorporate aspects of neuromuscular system training into your workouts? Do you use fixed axis machines?  Do you know how to best prepare for an upcoming (amateur/weekend warrior) competition?


If you are interested in learning more about functional training, specificity of training, or how to formulate your exercise program to meet your needs, email me at or find a local a physical therapist (via your state’s physical therapy association) and/or CHEK practitioner ( .


Written by Dr. Allison Mitch, PT (DPT)

RYT 500, reiki master

Please do not copy this material. All writing is copyright protected. 


Citations and recommended reading:


How to Eat, Move, and Be Healthy by Paul Chek

Summary of Paul Chek article that addresses fixed axis machines:

Paul Chek on Functional Training