FAQ'S PAGE THREE
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3. I've been fit before and get a variety of different recommendations from individual fitters on how to fix my particular issues. For the same problem I'll get 10 different suggestions. How are my personal irregularities and imperfections taken into consideration with the CPS? Each individual is different, unique, has irregularities and various “imperfections”... that's right!  This is completely natural and the human body adapts to these irregularities through a variety of strategies.  Moreover, currently the whole of the medical community agrees on the following principle:  one should not seek body symmetry at the risk of aggravating or creating pathologies/injuries.  The correction (wedges or other devices to compensate for a shorter leg) is only necessary to treat the pathological cases (0.9% of the cyclist population).  For example, the treatment of a shorter leg is not necessary for a difference that is less than 15mm. And, "leg length discrepancies" must be properly diagnosed. In most cases, someone with a TRUE leg length discrepancy will have had problems in their daily function OFF the bike and will have sought medical advice already, with the x-rays in hand to prove so. All other "diagnoses" of leg length discrepancies must be viewed as inaccurate.

The lateral balance of the human body in the biomechanical and muscular plan is a vast and purely theoretical concept because of innate genetic orientations or possible evolutions related to the sporting practice. In fact, nobody is strictly symmetrical.  In all disciplines of endurance--more particularly in the mechanical sports, like cycling--an imbalance can generate consequences at the articular, muscular or tendon level.  Additionally, there are also significant risks for a decline in energetic efficiency. In cycling, which one calls "rocking of the hips" is often the immediate consequence. A control of these muscular imbalances can be carried out on an isokinetic apparatus with concentric or eccentric rate, which makes it possible to measure the Force, maximum, at slow and fast speed, and the endurance of Force of the muscular groups of the upper limbs and lower. For cycling, these measurements relate to primarily the quadriceps and the hamstrings.  In practice, it is considered that symmetry is "Normal" for side variations of force lower than 5 %. Because it is not rare to find differences from 12 to 15 %... For the Elite, the rebalancing would be necessary for an upper deviation than 8 or 10 %, either by a specific work of musculation, or with the same apparatus which is infinitely more effective.  But these muscular analyses and treatments are rare, even in high level sport. These problems are very badly known, require expensive material (such an isokinetic apparatus is worth approximately $125,000) and depend on highly specialized physiologists.  With regard to the dimensional asymmetry, which in all circumstances must be checked by radiography/x-ray, the problem can be solved in a way much simpler and especially effective. First of all, one should not confuse a crippling pathology which concerns orthopaedic issues, with a mechanical affection of a rider who wishes to preserve or improve performances.  However there are nothing identical between the position of the foot during walk or the race and that which one notes during the cycle of pedal-stroke.  In the first case, it is the heel which ensures the contact with the ground.  Whereas in Cycling, the continuity of the transfer of the power is carried out on the level of the axis of the metatarsal.  Without approaching the complex analysis of the angulation of ankle, it is easy to understand that one can compensate for this difference in length by lowering a little less the heel of the "short leg", with the passage at the point died low, in the cycle of pedal-stroke.  Neither the rotation of ankle, nor cycle of transmission of energy, are at all affected.  According to our own experiment, one can quickly acquire this practice at some exits of drive with a minimum of attention.  Our measurements also confirm that one can adapt to 15 mm of difference between the lengths of legs of a cyclist, without affecting performance.  Whereas any mechanical modification of the transmission, fixes under the shoe and especially the cranks different lengths - prove to be unsuited on the physiological level, because they cause a dissymmetry in the transfer of the power. The binomial strength-speed, bases transmission of energy, would be distorted at the rate/rhythm of rate, that is to say 100 times per minute.  A complete study of dissymmetry would thus require these two analyses.  Also, one should understand that the shortest leg is not automatically the less powerful. As you can see, the issues are quite complex. To speak about them correctly, a high level of knowledge, education, and research is required.  (MORE)