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Low Back Exercise: Separating Myth from Fact

Many low back exercise programs through the continuum from rehabilitation to performance are based on the philosophy to enhance the range of motion and build strength. Yet performance often depends more on short range stiffness, rate of muscle activation/deactivation and technique to minimize “energy leaks” and optimally “steer” strength. At the rehabilitation end of the spectrum, many of these programs fail – either more patients are created or are exacerbated. Often, the causes of the back troubles are replicated in the exercises! Unfortunately, while many exercises are promoted as stabilization exercises, and specific muscles are claimed to be the most important stabilizers, the fact is these claims have been made without the quantification of stability. What is myth and what is factual? While my textbook elucidates the mechanisms, a few thoughts are provided here.

The Ultimate Approach

Building the ultimate back follows a five stage process that ensures a foundation for eventual strength, speed and power training. It is emphasized that these are only a few examples that may or may not be suitable for an individual. Generally rehabilitation approaches focus on Stages 1 to 3. Performance objectives include Stages 4 and 5:

Stage 1. Groove motion patterns, motor patterns

Stage 2. Build whole body and joint stability

Stage 3. Increase endurance

Stage 4. Build strength

Stage 5. Develop speed, power, agility

Ab walkout Figure 1. The “ab walkout” is a beginner's superstiffness exercise.

What is “Superstiffness?”

Become familiar with “superstiffness,” and performance will be enhanced and injury risk reduced. I have listed seven essential components:

  1. Rapid contraction and then relaxation of muscle - I have measured muscle contraction in many top athletes. Their ability to rapidly contract muscle is astounding, but even more astounding is their ability to rapidly relax the muscle. Too many coaches train for speed with more strengthening approaches – actually slowing the athlete down. A muscle that cannot relax quickly will slow the athlete.
  2. Tuning of the muscles - Consider the abdominal wall, which is employed as an elastic spring for many athletic endeavors. The thrower, kicker, runner or golfer all employ the abdominal spring. Storage of elastic energy in a compliant spring, or a soft spring, is rapidly dissipated or lost. This happens if the muscle is not activated to a sufficient level. If the spring is too stiff, then elastic energy storage is hampered because there is minimal elasticity and no movement. From our work examining several different rapid loading situations, it appears that a pre-contraction level of about 25 percent of MVC creates the amount of muscle stiffness for optimal storage and recovery of elastic energy in the core muscles (at least in many situations).
  3. Muscular binding and weaving - When all muscles at a joint stiffen together, a “superstiffness” phenomenon generally occurs. The total stiffness at a joint suddenly becomes more than the sum of individual muscle stiffnesses. Consider the abdominal wall in creating “core stability.” The three layers of the abdominal wall have fibres that run in different directions. This architecture is similar to that of plywood where one layer has the wood grain running north and south while the next layer runs east and west. The layers are bound by glue forming a composite material. Rectus abdominis, external and internal oblique and transverse abdominis form a composite when activated together. They appear to bind together when all are active to create a super stiffness that is higher than the sum of each individual muscle.
  4. Directing neuronal overflow - The phenomenon of strength training one arm, but not the other, with subsequent strength gains in the untrained arm is well known. Of course, there will be some enhancement in motor patterning, but there also appears to be neuronal overflow to the unexercised arm accounting for some of the enhancement. Rehabilitation clinicians use the phenomenon to enhance strength at a compromised joint. In principle, contraction at other joints is utilized to “squeeze” the neural drive back to the joint where enhanced performance is required. Eliminate “soft spots” with superstiffness technique.
  5. Eliminate energy leaks - "Energy leaks” are eliminated with technique so that concentric contraction at stronger joints does not force unwanted eccentric contraction at weaker joints. Consider the leaper in basketball. The planting foot is flat on the ground, and the power source is primarily the hip. The hip is so powerful in rapid extension that if the foot plant was on the ball of the foot, the foot would be forced flat to the floor, the ankle extensors forced into eccentric contraction and energy lost. (This is why I am continually puzzled by coaches who train ankle extension with ankle/heel raise exercises in their leapers). The focus should be on plyometric hip extension!
  6. Get through the “sticking points” - In many strength tasks, there is a “sticking point,” a compromise of joint torque or strength, which results from the biomechanics linked to muscle architecture. The weaker joints are stiffened, and the stronger joints supply the power. Modifications of the principle include “spreading the bar” during the bench press and “spreading the floor” during the squat.
  7. Optimize the passive connective tissue system - For years, coaches and trainers have been ruining athletic performance with inappropriate stretching. Consider elite runners. They are elite because they run, to a large extent, on passive tissue and not muscle. They are kangaroos! In fact, they are able to stiffen their passive tissues further with muscle activation given the many ligamentous and fascial connections. This ability is enhanced with plyometric training (which is often accomplished by simply performing the actual task) but is compromised with stretching. For example, a general guideline is to never stretch a runner beyond the joint angles utilized in running. Keep them tight to engage the springs with each stride. This is a form of superstiffness.

Superstiffness is used by the best football hitters, golfers, martial artists and weightlifters. Consider the hit in football where maximum speed of approach requires the combination of sufficient stiffness and compliance. But at the instant of impact, a total body stiffness is generated by rapid contraction of all muscles. This is what makes the impact so devastating by some. Breaking the board by the martial artist requires the skill of compliance (relaxation) to build speed but with rapid superstiffness just at impact. Splitting wood with an axe uses the same technique. The professional golfer who has a relaxed backswing but rapidly obtains superstiffness at ball impact is the one who achieves the long ball. The one who tries to swing too hard too soon actually decreases speed of movement with inappropriate stiffness. Muhammad Ali, Bruce Lee and Vasily Alexeyev all knew the secret of superstiffness. Understand the relationship between speed, compliance and stiffness, and you will be achieving ultimate performance.

Previously published on PTontheNet