Simple Guidelines For the Development of Flexibility.

FEXIBILITY IS INTRINSIC TO every skill or technique, no matter how simple or complex. Its role is obvious in activities where the athlete moves into extreme ranges, such as during a wind-up or follow-through.

In the August 2000 issue of C&AD, I stated that many training approaches seem to work for student-athletes because their needs are so remedial. The good news is that training tactics don't have to be too advanced or specialized because of the availability of such a wide range of abilities to call upon.

The bad news is that flexibility development is often neglected during critical periods, especially the adolescent growth spurt. Since fitness qualities are interrelated, this can detrimentally affect speed, strength, coordination and overall athleticism (as well as risk of injury). They must be developed collectively.

Allow us to present some basic principles and recommendations for flexibility development. Not the last word on the subject -- just a set of simple guidelines that we provide for our athletes.

Methods

Flexibility is trainable. It is also movement-specific, which is why an increase in single-joint range of motion is not the only objective. Through a combination of functional mobility and strength development, the athlete's muscles and tendons can be increased in length (as well as girth), elasticity and resiliency; and in their ability to act in an elastic-reactive manner during athletic movements.

The net result is improved mechanical and metabolic efficiency, technical proficiency and injury resistance.

Dynamic vs. Static. There is an ongoing debate about the role of dynamic vs. static flexibility in sports, and about how it should be developed. The prevailing theory seems to be that dynamic movements develop active mobility, and have an excitatory effect when performed prior to athletic tasks. Static stretching, on the other hand, develops passive mobility and is believed to be beneficial after activity. Due to its inhibitory effect, however, it may be detrimental if performed prior to training or competition.

Power and flexibility training are synergistic. Optimal results are achieved with a three-pronged approach. As is the case with any physical quality, the key to applying these methods lies in their skillful combination rather than exclusive or disproportionate use of any one of them:

* Elevating muscle metabolism and temperature with a dynamic warm-up. A rule of thumb is to engage in priming activity where the athlete begins to perspire lightly and has a flushed appearance.

* Performing dynamic, functional exercises through an optimal range of motion. This improves the athlete's "active mobility".

* Performing flexibility exercises at the conclusion of a training session and/or during recovery breaks (after catching your breath, while your muscles are fully warmed and flushed).

This improves the "passive mobility" that effectively acts as an athlete's flexibility reserve. There should always be time for mobility training because recovery periods should be regularly included between sets or series, as well as at the end of a workout.

Techniques

Individual. The reverse of a strength-training movement is usually a flexibility exercise for the same muscle group. The athlete should be positioned so that each stretch is felt in the belly of the muscle(s), not in the joint(s). A protective "myotatic" reflex causes the initial tension or tightness.

In order to have a beneficial effect, stretches must begin gradually and be held long enough for this reflex to subside. The athlete should therefore be directed to stretch statically -- without bouncing -- to his/her comfort limit for at least 8-12 seconds, relax and repeat. The athlete should be able to lean a little further with each rep. As mentioned above, this type of stretching may be most appropriate at the conclusion of a workout.

Partner-Assisted. Here is a simple but advanced partner-assisted technique that overrides reflex feedback and yields superior results. It is especially effective if done after 1-2 static stretches (at the conclusion of a workout):

1. Achieve and hold a stretched position for a minimum of 8-12 sec.

2. Have a partner hold you in position while you build up isometric tension in the stretched muscle(s) for an 8-count. Do not attempt a powerful contraction; force development should be gradual and reach 1/4 of maximum.

3. Release the tension and achieve a new, advanced stretch position; hold 8-12 sec. Repeat the procedure.

Assisted stretching is often incorrectly thought to be synonymous with "Proprioceptive Neuromuscular Facilitation". Although intermittent stretching-relaxation techniques have been borrowed from PNF (e.g., contract-relax, hold-relax, slow-reversal-hold-relax), PNF is not just a method of developing mobility in the strict sense of the term. It is a system of training techniques and procedures that exploits certain reflexes, and can be used to condition the neuromuscular system in various ways. (A detailed explanation is beyond the scope of this article and expertise of the author.) The salient point is that PNF methods can be used to augment flexibility, among other qualities.

Plyometric. Ballistic actions, or "plyometrics", usually are not aimed at increasing range of motion. They are primarily a means of improving explosive-reactive ability by exploiting neuromuscular reflex potentiation and musculotendinous elastic energy recovery. Overall working effect (e.g., power, impulse) and mechanical efficiency are increased; and muscle stiffness and motoneural activation are up-regulated.

Ballistic movements like running, jumping and explosive changes in speed and direction involve spring-like muscle actions where the tissues are rapidly and forcibly lengthened or "stretch-loaded", and immediately shortened or recoiled in a reactive-elastic manner.

This eccentric-concentric coupling action -- referred to as the stretch-shorten cycle -- is especially prevalent in athletic tasks, and is a distinct capability. Graphically, this can be illustrated on a force-velocity curve as the rapid and efficient transition from eccentric to concentric muscle action. In a practical sense, it is the ultimate expression of dynamic mobility and strength. The take-home message is to progressively include plyometric movements in combination with basic power and flexibility training.

Practical Considerations

Mobility vs. Stability? There is a common misperception that joint stability must be compromised in order to achieve advanced levels of mobility. The two are not mutually exclusive; and in fact a progressive, complementary approach is the key. At a foundational level, it is important to determine whether the athlete can actively move into the positions or ranges required to safely and effectively execute the tasks of his/her sport.

As was mentioned previously, many athletes have flexibility deficiencies resulting from neglect during sensitive developmental stages. Certainly passive stretching can be useful -- at least initially -- in correcting such limitations.

Keep in mind, however, that passive or static range of motion is only part of the answer. The athlete must have stability in motion. As is the case with strength training, the 'agonist/antagonist' or 'isolationist' (single-plane, single-joint) approach to mobility training is unsound. Most of the major muscles act in functional task groups, across multiple joints and planes. They should therefore be targeted with skillful, multi-planar movements where forces are transmitted and summated through the kinetic chain, not isolated within segments of it. Synergy is the operative concept regardless of the quality being developed.

Evaluation. Vern Gambetta, President of Gambetta Sports Training Systems in Sarasota, FL, makes a good case against contrived flexibility tests like the "sit-and-reach." He points out that actual athletic performance is the best measure of mobility, strength or any fitness quality; and that there are no universal tests for them.

"Functional flexibility is best exhibited by economy of movement in the desired sport skill," he explains. "Is the athlete smooth in his or her movements? Can he or she get in the required positions dynamically? Has there been a pattern of injuries?" While the third of these criteria is relatively straightforward, the first two often require a keen eye -- or in many cases, videography or other biomechanics (e.g. digitizing) equipment -- in order to accurately analyze them at full speed.

Functional profiling by a skilled physical therapist is another useful tool, but is also impractical for many athletes and coaches. I would therefore like to recommend a simple means of evaluating an athlete's ability to get into the "universal athletic position." The knee-bend flexibility test can be a useful means of assessing composite range of motion. It's easy to administer, and the only equipment required is an inexpensive goniometer:

1. Allow 10 minutes for the athlete to warm-up, do mobility drills, etc.

2. Place the feet in a natural shoulder-width stance, holding a broomstick overhead at arm's length (alternatively, the athlete may interlock his/her fingers behind the head).

3. Squat as low as possible while maintaining balance, keeping the feet flat on the floor and trunk as upright as possible.

4. Measure the knee angle achieved in the bottomed-out position by aligning the goniometer with the midlines of the thigh (using the axis of the greater trochanter and lateral epicondyle) and lower leg (using the axis of the fibular head and lateral malleolus). Rock-bottom for most athletes is usually 145[degrees], although some can achieve up to 155[degrees]. In my experience, 120[degrees] is the danger zone.

This test is not intended to replace other flexibility indices, but rather to be used in conjunction with various composite or single-joint tests to identify specific ranges of motion. Its limitations are that it does not provide an indication of dynamic or rotational mobility. It is, however, a useful starting point for evaluating general static flexibility for many activities.

Sound easy enough? Do a quick self-check before you blow it off and turn the page: If the athlete can't sit down far enough to get his/her thighs below horizontal while keeping the heels down and head up, it's time to move flexibility up on the priority list. You can't use it if you can't move it; and there is time for mobility if there is time to train!

Quality. The same principle applies to all aspects of training: You get out of it what you put into it. Strength and flexibility are interdependent, whereas the lack of either one is a leading cause of nonathleticism, technical inefficiency and injury. Flexibility exercises are not a motion we go through just because some textbook says so. You will enhance your athleticism and "injury proof" yourself by skillfully combining the methods of mobility development; and won't if you don't.