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What is Functional Exercise?


Func.tion.al 1. capable of operating or functioning 2. having or serving a utilitarian purpose; capable of serving the purpose for which it was designed.
(Webster’s Encyclopedi
a Unabridged Dictionary of the English Language, 2nd Edition, 1996)

The word “functional” is commonly used to indicate “useful”, “applicable”, or something that works. Today there are gym programs and trainers, therapists and rehabilitation clinics, chiropractors and doctors all claiming to provide or prescribe “functional exercise.” Are these programs actually living up to the meaning of the term “functional” with regard to exercise prescription, or are they riding yet another fad? To answer this question, I would like to share the guidelines used for prescribing “functional exercise” at the C.H.E.K Institute (Table 1).

Characteristics of Functional Exercise

  1. Comparable Reflex Profile (Righting and Equilibrium reflexes)

  2. Maintenance of your Center of Gravity over your own base of support

    • Static postural component

    • Dynamic postural component

  3. Generalized Motor Program Compatibility

  4. Open/Closed Chain Compatibility

  5. Improves Relevant Biomotor Abilities

  6. Isolation to Integration

Table 1

1. REFLEX PROFILE

As upright human beings, we must move across the earth in a field of gravity. That is first and foremost! On a day to day basis, we do everything from climbing mountains, working at construction sites and factories to riding subway trains, buses, motorcycles and skateboards. Each activity we do requires activation of special reflexes intended to protect us from hurting ourselves. These reflexes provide us with such abilities as putting your hands out to catch yourself to regaining your balance when the bus takes off before you have had a chance to get seated. These reflex reactions are commonly broken into two major groups:

The majority of our righting and tilting responses should be built into the nervous system before three years of age (1).

Righting reactions can be broken into five different reflexes that serve to keep the head in a normal position, right the body to a normal position and adjust the body parts in relation to the head and vice versa (1). These reactions are called:

a. Labyrinthine righting reflexes acting on the head
b. Body-righting reflexes acting on the head
c. Neck-righting reflexes
d. Body-righting reflexes acting on the body
e. Optical righting reflexes

Labyrinthine righting reflexes

Stimulation of the proprioceptors of the labyrinth causes changes in tone of the neck muscles, which bring the head into its natural position in space.

Body righting reflexes

Reflex effects upon the neck muscles, which bring the head into the correct position in space caused by stimulation of pressoreceptors in the body wall by contact with the ground.

Neck reflexes

Changes in position of the head cause alterations in tone of the neck muscles through stimulation of proprioceptors in the labyrinth, which bring the head into its correct position in space. Stimulation of proprioceptors in the neck muscles in turn causes reflex movements of the limbs which bring the animal into the normal position in relation to the head.

Table 2.

In addition to righting reactions, we have equilibrium reactions. These reactions are developed in us as children and are for the purpose of maintaining or regaining control over the body’s center of gravity so we will not fall. According to Barnes, there are several categories of equilibrium reactions (2):

a. Protective reaction of the arms and legs
b. Tilting reactions
c. Postural fixating reactions

Although there are many work and sports activities that require both righting and equilibrium reactions, there are also numerous activities that require predominant use of either righting or equilibrium reactions.

Righting reactions tend to be dominant when moving across a fixed or stable surface, such as a sidewalk, or even a balance beam in gymnastics, which is fixed to the ground. Equilibrium or tilting reactions are more dominant when the supportive surface moves underneath us (3). For example, activities such as wind surfing, working on a fishing boat in the open sea, riding a horse, a motor cycle, or a subway train are examples of activities using righting and equilibrium reactions together, but that may require equilibrium-dominant reactions.

Consider riding a subway train; if you’re not holding onto the pole in the subway car when it takes off and you have slow tilting reflexes, you know what will happen! (See Figure 1.)

Figure 1

The same could be said of any activity that requires a reflex response to maintain an upright posture or protect the body. In fact, Vladimir Janda stated that if we could speed the reflex response of our bodies by 50%, we would reduce the chances of acquiring an orthopedic injury by about 80% (4).

Application

When selecting exercises for your patient or client, it is important to consider which is the dominant reflex profile in the activity for which they are conditioning. In sports such as equestrian activities, surfing or motor cycle racing it is very important to determine which aspect of the task is most challenging to your client.

Example problem 1: A moto-X racer has a hard time sliding through corners, but can handle straight-away riding and jumping.

Solution: They are likely to benefit from exercises that emphasize the tilting aspect of an equilibrium response. In this instance, kneeling on a Swiss Ball and catching medicine balls tossed to you from the side (Figure 2) would aid in improving the rider’s ability to respond more quickly to the motorcycle when sliding through corners.

Figure 2 - Moto-X Racer kneeling on a Swiss ball catching medicine balls catching a medicine ball while kneeling on a Swiss ball (which will mmediately express any change in the racer's center of gravity) provides an opportunity to enhance the racer's reflex profile in an environment with similar demands as sliding a moto-X bike through a corner on a dirt track.
The ball will move under the racer, much like the race bike as it loses traction in the slide, while catching the medicine ball will quickly alter the racer's center of gravity relative to his base of support, necessitating an immediate equilibrium response to prevent falling.

Example problem 2: Another moto-X racer is fine in the corners, but has a hard time controlling the bike through rough sections of the course due to lack of strength or strength/endurance (see Figure 3-A).

Figure 3 A-B - Moto-cross Rider A. The racer must maintain his center of gravity over his base of support, which is unstable during a moto-X race and continues to be unstable during the Swiss ball kneeling bent-over row (B). Although righting and equilibrium responses are activated in the body at the same time, for a moto-x racer, this exercise will be much less challenging to the equilibrium response than the exercise in Figure 2., particularly with an equal load in each hand and movement predominantly in the sagittal plane, just as straight-away riding.

Solution: A circuit emphasizing righting responses would be useful, such as a circuit consisting of a series of exercises organized in a sequence of descending neurological demand, e.g. kneeling on the Swiss Ball (see Figure 3-B), single leg stance exercises and finally two-legged stance exercises would prove to be very beneficial. Examples of exercises include kneeling on the ball plus single arm cable pulling and alternating left and right sides. Then progress to single arm-opposite leg cable pushing, to single arm abductions with a dumbbell (standing on the same leg), alternating between left and right sides for equal reps, and finally finishing with a bout of body-blade work. The intensive interval method (~ 30 seconds per exercise) would be preferable. After 1:00 rest, the circuit would be repeated and this would be done for as many as 5-10 times, depending on the condition of the moto-X racer. The key factor in selecting work volume would be making sure fatigue was not developing or reinforcing bad motor skills that may hinder his racing performance.

Using a protocol such as one of the above will certainly serve to enhance postural reactions, regardless if your intention is to focus on improving righting or tilting reactions. This is important for the maintenance and development of any client or patient’s reflex profile, as well as for developing sound motor engrams (expanded upon below).

2. MAINTENANCE OF YOUR CENTER OF GRAVITY OVER YOUR BASE OF SUPPORT

In most activities of daily life (aside from sitting in a chair, driving a car, or using most of the “non-functional” machines littering the gyms worldwide), we must maintain our center of gravity over our own base of support. Maintenance of your center of gravity over your base of support, or your balance, is so important that most of us master it within the first 24 months of our life.

If your center of gravity goes outside your base of support, you are very likely to fall over. The only exceptions to the rule are cases where your own inertial energy will hold you up, such as an ice hockey player turning real fast (Figure 4) or when you are being supported by an outside force, such as the wind while riding a sail board (Figure 5). In functional situations such as those demonstrated in Figures 4 and 5, you must draw heavily on your body’s ability to integrate muscle groups and on your righting and tilting responses.

Figure 4 - Ice Hockey Player. When turning, the hockey player's center of gravity is well outside his base of support. He is supported by his inertial energy and his connection to the ice by his sharp skate blades. Should he lose footing or be stopped abruptly, you can clearly see that he would fall over unless he repositioned one leg under his center of gravity (indicated by arrow). Figure 5 - Windsurfer. The windsurfer uses the force of the wind and support of the boom to maintain a body position in which her center of gravity (see arrow) is significantly displaced from her base of support. Should the wind suddenly stop, she would be unable to maintain her balance due to the lateral
displacement of her center of gravity. Maintenance of her position while windsurfing requires constant integration of her body segments with the action of the sail and board. This requires constant activation and utilization of all aspects of righting and equilibrium responses.

If you consider a typical daily activity such as putting a suitcase in the trunk of your car (Figure 7), it become obvious that your nervous system must be capable of integrating both static and dynamic postural functions (5). To better appreciate these terms, let’s explore them individually.

Static postural stability

When standing upright, the force of gravity will actually serve to assist in stabilization of a well-aligned body. In fact, I am sure most of you know of people that can’t stand still for very long without feeling pressure in their neck or back, which often leads them to “auto manipulate” or self-adjust in attempt to decrease activation of mechanoreceptors in ligaments and joint capsules surrounding the subluxed joints.

When you lean forward in a field of gravity, there is what is termed a flexion moment placed on your body; leaning backward or behind the mid-frontal plane produces an extension moment. As you lean progressively further forward, the “moment” increases because more of your body weight is forward of the axis of rotation; the flexion moment rises very fast even during the first 30° of forward bend (6).

The larger the flexion moment, the harder your extensor muscles have to work to keep you from falling over. When holding an object in your hands, such as the suitcase shown in Figure 6, the flexion moment rises in proportion to the weight you are holding, and therefore the work that must be done by your body to keep you upright rises. To appreciate the concept of static stability, consider how tired your back can get while simply leaning forward over a sink to brush your teeth, then add the weight of a suit case and the additional load created by the lever arm of your trunk and arms and you can quickly realize why people hurt their backs going on vacation!

Figure 6 - Suitcase in trunk of car. When bending over to pick up a suit case or any weighted object, the erectors of the back and hips must activate to support the trunk as a working platform (static stability). The concept of stability can be seen during such activities as putting on make-up or brushing your teeth, where you torso is held in a specific position against gravity. Dynamic stability as seen here relates to the fact that as the suitcase is transferred into the car, the joints must be dynamically controlled so that joint health is maintained and the body is not injured. When the stabilizer mechanisms of the body work correctly, an optimal axis of rotation is always maintained in each joint complex. Figure 7A-B. A. Optimal Instantaneous Axis of Rotation
When maintaining a concentric axis, the two joint surfaces will not move away from each other under influence of a rotational force.
B. When stabilizer and/or joint function is aberrant, and eccentric axis of rotation may exist, during which joint surfaces move away from each other. An eccentric axis of motion is commonly associated with ligamentous stress and joint derangement.

Static stability then, is holding your body in any position that allows you to carry out a goal or task against the load of your extremity(ies), trunk, and any other additional load handled by your body. In Figure 6, the person putting the suitcase in the car must have adequate static stability to hold themselves up in a field of gravity. Failure to have adequate static stability in the muscular system will result in pathological loading of ligaments. Clinically, this is a common source of joint instability, particularly in the lumbar spine.

Dynamic stability

The definition I have developed for dynamic stability is:

The ability to maintain an optimal instantaneous axis of rotation in any joint or combination of joints in any space/time combination”.

To better understand the concept of dynamic stability, let us continue to use Figure 6 as a working example. Where static stability provided the working platform from which the suitcase could be picked up and moved from the ground into the trunk, dynamic stability requires that each joint complex in the body be stabilized by its respective stabilizer muscles in such a way that it functions within the parameters necessary to maintain optimal joint health. For example, from the forward bent position (static stability), the arms primarily change the location of the suitcase (relative to the body) and handle the load dynamically. Therefore, we can consider that the rotator cuff and even the large muscles around the shoulder must be intelligently timed to make sure the shoulder joint does not get damaged by the load; the same principle applies to all parts of the body involved in the dynamic transport of the load.

When the joint stabilizers are healthy, the joint will maintain a “concentric” axis of rotation. (There are exceptions to this rule, such as in a joint complex with multiple axes of rotation. For the purposes of explanation, we will keep it simple and stick to the concept of maintaining an optimal axis of rotation.) A concentric axis of rotation results in the joint rotating toward or around its optimal instantaneous axis of rotation (Figure 7A). This would constitute good dynamic stability. If a joint complex is not stabilized properly, any load, be it intrinsic or extrinsic, will impart an eccentric rotation to the joint complex. An eccentric rotation is one in which the joint surfaces move away from an optimal instantaneous axis of rotation or centric rotation, producing an eccentric axis of rotation (Figure 7B). An eccentric rotation of any joint complex (particularly under load) may produce what is commonly referred to as a subluxation by chiropractors; a luxation is a dislocation of the joint.

Application

To develop functional strength with a high level of carryover to work, sport or recreation, we must utilize the principles of static and dynamic stability through optimal selection of exercises. It should be immediately apparent that if you are using a machine that supports the body in any way, (particularly seated, prone, supine or leaning types) you are not activating the body’s static stabilizer system, or postural system. This is a critical concept to grasp when you consider the harsh reality that stability must always precede force generation. As the old saying goes, “you can’t fire a cannon from a canoe!” This is exactly why you so often see a huge difference between your performance, for example, during a Smith squat and a free squat, or even more dramatic, the difference between your leg press performance and squat or deadlift performance.

To make things even clearer with regard to the difference between machines and functional exercise, consider that any time a machine guides the load using a fixed, or even semi-fixed axis of motion, there is a reduction in the need to recruit your own intrinsic and extrinsic stabilizers. A dramatic real-time example of dynamic stabilization is seen whenever you introduce a novice lifter to an exercise as simple as a dumbbell bench press; the dumbbells look like they have a mind of their own for the first several training sessions. Take the dumbbells out of the hands of that same client’s hands and walk them over to any chest press machine and they will perform as though they were born in a gym.

Quite frankly, it really doesn’t matter how strong you are on any machine exercise. To go one step further (this may upset some of the meat-heads of the world), there is a VERY POOR correlation between your strength during any supported lift (bench press, prone row, Smith squat or split squat…) and any functional lift or task such as breaking through the line in football, controlling an opponent in wrestling, or making it through the slalom course in water or snow.

Among the reasons for this are:

Figure 8 A & B A) Classically, an athlete that spends all the time it takes to develop a "big bench" will lack integrative training or ability. B) Most of the "big benchers", or even "little benchers" that train with isolation techniques perform very poorly during the "Standing Single Leg Cable Push Test".

By now I am sure you are wondering how to apply all this information. Well, quite simply, choose exercises that have a high correlation to the functional demands of your client or patient’s work or sports environment. Place these exercises before non-functional exercises in any workout because they demand much more neurological energy, plus form degenerates very fast if functional exercises are attempted after the body is fatigued from other exercises. I only allow two exceptions to this rule: firstly when conditioning an elite athlete who is very experienced at weight training and needs to have their nervous system challenged. Secondly, during a base conditioning program where mass is of greater concern than neuromuscular integration training. In this case, simply remember the rule I presented in Scientific Back Training (9), “If you are going to isolate, you must then integrate!”

3. GENERALIZED MOTOR PROGRAM COMPATIBILITY

The concept of generalized motor programs as a means of storing motor programs was put forth by Schmidt (10). One of the primary reasons motor learning experts have explored the concept of the generalized motor program is because many believe that the brain does not contain adequate storage capacity to hold the myriad of programs one could generate throughout a lifetime of movement. Schmidt has proposed that the brain stores movements that have the same relative timing as generalized motor programs. A typical example of a generalized motor program is easily found in the squat movement pattern. I am sure most of you are well aware that research clearly shows there is a very poor carryover from isolation exercises such as knee extensions, hamstring curls and even the leg press with regard to improving one’s vertical jump. Yet, at the same time, research clearly shows that resisted squat training provides significant improvement in vertical jump performance. This fits beautifully with Schmidt’s theory of the generalized motor program, as the squat and the jump are very close to the same movement pattern; the same could be said for the power clean and the vertical jump.

Years ago, before finding Schmidt’s research, I was having great success in the rehabilitation of my orthopedic patients using a system I developed, which I call the Primal PatternÔ System. Using my interests in anatomy and developmental man, I hypothesized that the selective pressures of evolution must have resulted in a human anatomy that was specifically designed to meet the demands made by nature. I also concluded that if one could not squat, lunge, bend, push, pull and twist from the standing position, or could not effectively ambulate (gait) then chances of survival would dwindle severely (11).

Today, we are nothing but cavemen with fancy clothing and desks. The harsh reality, a reality I have seen literally thousands of times in my practice, is that when any human cannot efficiently perform any of the primal patterns described above and at a level of subconscious competency, there is almost always injury lurking, if not present.

Another reality is that the body can very effectively compound primal pattern movements to create other movements. A very simple and common example of this can be both seen and experienced by either watching someone throw a rock or a ball. To propel the object, the body performs a lunge, followed by a twist, and summates these movements with a push in the form of medial shoulder rotation, elbow extension and accessory movements at the wrist and hand.

Although I could go into great detail as to how I apply this system in both rehabilitation and sports performance for both evaluation and conditioning, I don’t have the space here. This is such an immense block of learning that it takes one full week of training to get my Level II interns to begin to effectively apply the system to solve movement problems; which is really not long considering people study movement for years in colleges and still have a hard time practically applying the information (The interested reader will be well served to review the correspondence course titled Advanced Program Design [11]).

Application

Based on my clinical experience and anecdotal research, functional exercises are most functional when they closely resemble a movement pattern that is commonly used in the client’s work or sports environment. The further one deviates from a pattern that has the same, or very similar general characteristics or relative timing, the less likely the exercise is to be fruitful for the end user!

It is my belief that the concept of the generalized motor program explains why so many forms of exercise simply don’t improve function or serve as optimal injury prevention. The subscriber to my theory could have an interesting time analyzing the literally thousands of exercises and numerous exercise systems. As I tell my students, don’t wait for some scientist to give you the answer when you can often come to sound and logical conclusions through clinical or practical experience. (For the interested reader, I have outlined how Swiss Ball training contributes to evaluation and improving of functional movement in my program titled Advanced Swiss Ball Training For Rehabilitation [12]).

4. OPEN vs. CLOSED CHAIN EXERCISE SELECTION

Although the concept of open and closed chain movements is under scrutiny by famous physical therapist Gary Gray and others, I find the principles to be very useful. Originally popularized in the medical literature by Arthur C. Steindler (13), an open chain movement can be broken down to mean a movement in which you (the exerciser) can overcome the object you are applying force to. It may also be considered as a movement in which the distal segment is free to move. A closed chain is said to exist if you can’t overcome the object that your body is pushing against, or a movement in which the distal segment is fixed. A simple example to illustrate the principles of open and closed chain movements can be seen when comparing the lat pull down exercise (open chain) to the chin-up (closed chain). No matter how hard you pull on a chin-up bar, you are not going to pull it out of a squat cage, but you will eventually pull your body past the bar being that the chain is closed and you have applied adequate force to lift your own body weight. The lat pull down, on the other hand, will be an open chain exercise until such time that you increase the load to the point at which you can no longer open the chain; at that point you will be doing a chin-up from the lat pull down bar (Figure 9)!

Figure 9 - Lat Pull Down (open chain) and Chin-up (closed chain).

Now, regardless what the various “industry experts” say about open and closed chain not being relevant, I suggest that anyone who has done any athletic training for sports such as rock climbing, gymnastics or even for military competitions, will soon tell you that the lat pull down exercise does very little to improve chin-up performance. In fact, if you look at the arthrokinematics of the two movements you will see that in the chin-up, you must pull your body past a fixed hand, while in the lat pull down, you must pull the load and your arms toward and across a fixed torso and rib cage. Therefore, it is safe to say that the recruitment pattern generated by the nervous system are 180° out of phase with each other!

To give you an example of how one movement performed 180° out of phase can be done, yet yield little results, consider a record player. If the record player turns clockwise at the correct speed, your get music; if it turns counter clockwise at the same speed, you get noise! The mechanics of playing the record, a turntable spinning at a set rate and vibration of the stylus are all the same, like the similarity between a lat pull down and a chin-up, yet the results yielded from training are very different, like the record player going forward to make music and backward to make noise. Both exercises can produce big muscles, but are the big muscles under optimal neurological command to perform the movement at task?

Application

To make the best of your training time with any client or patient, try to choose exercises that resemble the environment of application with regard to open and closed chain principles. It’s that simple in most cases.

5.FUNCTIONAL EXERCISE IMPROVES RELEVANT BIOMOTOR ABILITIES

Biomotor can be broken down into its component parts to give its full meaning: Bio = life and Motor = movement. Tudor Bompa describes the importance of biomotor abilities in his book Theory and Methodology Of Strength Training (14). In short, biomotor abilities consist of such qualities as:

Understanding the concept of biomotor abilities is important when determining how functional an exercise is when you consider that most functional exercises, as dictated by the guidelines presented here, address multiple biomotor abilities, event though the focus may be on one specific biomotor ability. For example, the multi-directional lunge exercise (Figure 10 A-E), regardless of acute exercise variable selection, will improve or at minimum serve to maintain some level of balance, coordination, flexibility and agility. By manipulation of acute exercise variables, you can also include power, strength or endurance as well.

Figure 10 A-E - Multi-directional Lunge Exercise

If you simply compare the multi-directional lunge, a functional exercise, to a Smith Machine split squat (the only machine based exercise that has any real relationship from a movement perspective), you will see that you are now down to flexibility and whatever force-generating quality you select via acute exercise variables. By using the machine for stabilization you lose the ability to improve balance, agility, and coordination beyond the inter-muscular coordination that is a given for any compound exercise, although even intermuscular coordination demands are less when stabilized by a machine.

Application

To determine how functional any exercise is with regard to biomotor ability and biomotor ability development, simply ask yourself these questions with regard to the exercise at hand:

Choosing the exercise that best addresses the biomotor requirements of your client’s challenge environment, and one that suits their motor skills development at that time can only serve to speed the rate at which they achieve their conditioning or rehabilitation goals!

6. ISOLATE, THEN INTEGRATE!

In the video correspondence course Scientific Back Training (9), I speak of my rule, “if you are going to isolate, you must then integrate.” I have always held this belief firm in my mind because of having been involved in rehabilitation from the very beginning of my career. As trainer of the US Army Boxing Team at Ft. Bragg, N.C., I saw many examples of what happens to good athletes that spend too much time on machines or isolation exercises of any type.

Movement for any work or sports environment regardless of what the exact type, requires that we develop movement, or motor skills. Isolation exercises are exactly what the name implies, isolating. Improving movement skill can only be accomplished by integrating. Now, don’t take that to mean that I think there is no place for isolation exercises, because there certainly is. For example, if someone has had a C5/6 disc bulge and developed atrophy of the deltoid and rotator cuff musculature as a result, I would certainly prescribe isolation exercises to induce hypertrophy as quickly and effectively as possible. What must also be done, to complete the picture, is to integrate these muscles and joints with the rest of the body.

Application

Using the above example of atrophy of the C5 innervated musculature of the shoulder, we would certainly have to develop the infraspinatus and deltoids of the involved shoulder. To do this, we would first work on isolation exercises for the rotator cuff. If the cuff was not strong enough to handle dynamic exercise for the deltoid, I would assess to see if isometric exercises were safe. If not, then we would first rehabilitate the rotator cuff to sufficient levels of function to accommodate deltoid exercises.

A classic example of progression for this case would be as follows:

  1. Isolation training for the external shoulder rotators
  2. 2. Integration for the external shoulder rotators
  3. 3. Isolation training for the deltoid
    – Isometric and or super slow tempo training first
    – Dynamic training for the shoulder with a fully functional rotator cuff
  4. 4. Integration training for the deltoid group:
    – Pushing
    – Pulling
    – Combined patterns training

CONCLUSION

This has been a brief summary of what the C.H.E.K Institute uses for guidelines to determine the validity of an exercise as “functional”. As you can see, virtually every exercise in the world can become functional at some point in a spectrum of rehabilitation. Part of the art, science, and skill of being good as a conditioning or rehabilitation professional is knowing when to progress the client in order that maximum opportunity for learning and development are not missed.

Paul Chek is publishing a book and audio tape on this topic - "Movement that Matters". If you would like to find out more please email info@chekinstitute.com

REFERENCES