CYFAC POSTURAL SYSTEM - FAQs
  • What is the Cyfac Postural System?
    The Cyfac Postural System (CPS) is a methodology for harmonizing the fit between cyclist and bicycle. The approach is distinctly modern in that it draws from multiple recent scientific, mathematical theories and developments, and information technology advances and applies these to a greater application of human physiology and ergonomics. The CPS is grounded in the latest scientific principles and medical advances; while the CPS was privately developped and remains a proprietary system, the same theories that support the CPS method feature in more than 2,000 independently published studies/articles detailing performance in endurance sports and cycling in particular. The Cyfac Postural System is highly sophisticated yet the actual application of the CPS method is simple, precise, reproducible, and comprehensible. Providing scientifically validated and generated results for the world's best fit is the CPS.

    More than 10,000 CPS fits have been provided to cyclists across the world, including more than 40 racers in the Pro peloton, cyclists plagued by nagging problems throughout their riding lives, and even horrifically injured riders originally told to forget getting on their bikes ever again.
  • Why was the Cyfac Postural System developped?
    Experts in the field of custom frame design and building, Cyfac now offers the complete integration of cycling ergonomics, ensuring that rider position and frame design are both born out of precise and scientifically-based principles. The focus is a fit that follows physiological foundations for cycling performance and not antiquated ideas that have little or no scientific basis. The CPS approach realizes that there is no consensus on bike fit and sees this as a fault of clashing personal theories (e.g., sprinters should be lower in the saddle, climbers and TTers higher in the saddle, the LeMond algorithm for saddle height, etc.). These personal and subjective approaches have either old suppositions (knee over pedal spindle dates back to 1979!) or no scientific data (the role of femur length) to support the theorizing.

    As such, most current fit methods take something of a trial-and-error approach and rely on the efforts of an individual fitting person. Adjusting one piece of equipment and then another while looking at a rider positioned on some type of static home-trainer or fit-cycle device is the general rule. These schools of thought suggest an artistry to bike fit because they are lacking in measureable criteria or scientific method. Limited personal theories, insistence that non-validated criteria (body symmetry, leg length discrepancies, a flat back, the rider "feeling" right) are important , and the inability to reliably duplicate results upon each fit characterize this type of approach. Fits done this way make a very large assumption, in that they begin with the rider's current position, which may be anywhere along the spectrum between optimal and damaging to the rider's health and performance. Changing one variable at a time is the rule. Unfortunately, the approach doesn't look at the rider comprehensively and restricts the human body in ways that coincide with a fitter’s personal theories, theories which are unsubstantiated and even proven inaccurate in the sports/medical/scientific community (e.g., using a plumb-line to determine the one “proper” position of the knee over the pedal spindle).

    The CPS method eschews the subjective persuasions and theories by residing in widely accepted physiological and ergonomic (as opposed to purely mechanical) principles. The CPS performs a multi-factorial analysis of the rider, considering each individual as more than just a skeletal system or points in space. The fully functioning cyclist’s body is accounted for: individual body measurements and a unique rider profile are analyzed through a lens that captures the rider's muscular, vascular, skeletal, and circulatory systems. Optimizing the body’s efficiency via the intense research and rigorous study at the base of the CPS is the focus.

    Driving the CPS method are scientific principles, rather than superficially empirical or “looks and feels right” subjective interpretations. Beyond the theorizing are full-scale clinical tests that placed real riders in real cycling situations to further enhance and substantiate the scientific-medical data serving as the back-drop.
  • How does it work?
    The CPS begins with a compilation of data gleaned from over 45,000 rider tests performed on more than 4500 individual riders. In preparation for each test specific positioning variables were changed with proper adaptive time given in between each test session. The protocol followed stringent scientific and statistical guidelines to ensure data integrity. Independently conducted and validated, the research serving as the basis for the CPS was completed at the Center For Sports Medicine in Lyon , France , a center that trains and studies the French National Soccer Team, members of the French National Cycling Team, and numerous other world-class athletes.

    Testing was designed to optimize the following criteria :

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    Comfort : To reduce fatigue – Aid recuperation – Eliminate soreness. How ? Limit muscular, joint, tendon tensions to properly work while on the bike and recover while off it.
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    Performance : Optimize power transfer at dead-spots - Optimize pulmonary and blood oxygen transfer. How? By optimizing the complex relationship between strength-cadence and muscular work. The more efficient your body, your cycling technique, your movement, the better you will perform
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    Health : Prevent joint, tendon, and muscular pathologies. How? By limiting joint amplitudes, by reducing muscle tension, by positioning less traumatically. If you are injured, you cannot support the work load proper training requires.
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    Aerodynamics : Limit frontal surface area exposed to the wind without generating any physiological or biomechanical constraints. A 3% increase in aerodynamic profile can generate a 10% decrease in physiological efficiency. Focus on the proper criteria.

    The parameters of the performance, comfort and health criteria are :

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    Optimization of the transfer of blood oxygen.
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    Optimization of the transfer of lung oxygen.
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    Optimization of the work of the athlete's muscular groups.
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    Optimization of the transfer of energy during transitional phases (improved flow of the pedal-stroke) .
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    Optimization of the articular working amplitudes of the lower limb joints (hip - knee - ankle) and of the upper body (lumbar-sacral hinge, scapular-humeral joint)
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    Optimization of lung ventilation.
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    Limitation of the excessive tendonous tensors connected to articular hyper request (hyper flexor or hyper extensor).
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    Limitation of the heavy labor of lower body muscles to limit the onset of post exercise muscle spasms.

    The research subjects were :

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    Aged 15 to 72, male and female.
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    Participated in all cycling disciplines (road, mtb, track, cross, triathlon, time trial).
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    Performed at all levels of cycling (tourist to top level professional).
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    Received comprehensive medical analyses with coverage of all pathological conditions.
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    Rigorously followed throughout the entire study. No subjects were allowed to let supplemental or deficient training affect the efficacy of position changes.
  • What research/testing went into the system?
    TESTING PROCESSES INCLUDED:

    * Biomechanical analyses:
    o Cinematic analysis and 3-D modeling of cyclists' movements.
    o Joint and muscle function analysis.
    o Kinetic analysis.

    * Physiological analyses:
    o Energetic cost analysis.
    o Analysis of muscular relations.

    Data from the 45,000 tests were treated via complex statistical processes used in the medical-scientific realm. Independent statisticians examined the information to find correlations and algorithmic relationships. Recurring patterns or, mathematical constants, were found to exist between 1. the actual physical measurements and data from the individual. 2. the adjustments to “positioning variables” and 3. the physiological performance of the individual. “Laws” and “truths” relative to the riding position and the physiological ramifications of even the slightest changes were manifest.

    The immutable points -- that joint amplitudes that should not extend beyond a certain point, that there are distinct limits on impeding the diaphragm, that the pedal cycle is a function of 3 successive dead spots, that the body adapts to most asymmetric traits including leg length discrepancies up to 15mm, that arm width on handle bars doesn’t have an impact on aerodynamics -- do not change across any individuals. There are constants that were uncovered and applicable to all cyclists whether you are a week-end rider or top level professional. The “variability” of the results and the indications that certain position refinements worked for certain people were tied exclusively to the individual anthropometric body measurements and the profile of the ONE unique athlete. On this level, true specificity and individualization of positioning was attained. The result is scientifically determined and ratified based on the extensive criteria outlined above.

    While this approach may seem to percolate all fits into the greatest common denominator it is in fact backed up by mathematical developments in so-called fractal geometry. The application of fractal geometry and the same statistical analyses used to create the CPS are found in diagnostic medical devices such as CAT scan machines and MRI equipment as well as in DNA sequencing protocols and numerous other scientific applications. The degree of sophistication and proven accuracy brings the idea of a “fit” to a new level.

    With the constants and laws validated during the research phase, the CPS was able to construct a database upon which to draw for fitting criteria across the spectrum of athletes’ abilities, ages, past injuries, riding disciplines, and morphological irregularities. It should be noted that the current database is constantly refined and updated. Each time a new athlete is studied via the CPS, their individual anthropometric body measurements and individual profile are treated through this database. The algorithms and formulas resulting from the research are applied to THIS individual’s numbers resulting in a unique fit that respects the scientific truths of the scientific medical establishment and the extensive testing undertaken to develop the CPS while considering THAT INDIVIDUAL’S own unique traits at the same time.

    Summary The CPS is the most comprehensive fit protocol commercially available in the cycling world. Rigorously validated, using the latest advances in the medical/scientific community, and simple to do, the CPS allows for unmatched sophistication, precision, and reproducibility in the fitting of all levels of cyclists. The end result of a CPS study is a position that takes into account optimized breathing, optimized oxygen uptake and oxygen distribution through the body’s cardio-vascular system, proper leg, arm, and body extension for comfort, sustained power generation, prevention of strain, and increased endurance/resistance to fatigue.
  • How does the CPS look at all the different factors - comfort, power, efficiency, experience, ability, body type, personal preference -- without more involved time spent talking to and observing the rider like other systems/approaches may do as they look at a rider on a bicycle and trainer set-up?
    There is no common vocabulary established regarding fit. As such, a long interview process and an over-reliance on subjective "feelings" or individual suppositions generates error. It's important to solicit information on riding level, yearly mileage (both indicative of the degree of muscular adaptation) and any information regarding pre-existing conditions that plague the rider on a daily basis, especially off the bike. But, almost every on-the-bike issue or problem comes from improper position, as we have seen with more than 10,000 fits,

    Still, of greater importance is that physiological function--the key determinant of comfort, performance, and health--simply cannot be perceived by the rider. Can you feel that your diaphragm isn't expanding completely, preventing you from optimizing oxygen uptake? Can you tell that blood flow has been constricted in your iliac artery, affecting oxygenated blood flow to your legs? Can you explain that poor foot stability has fatigued your foot/ankle/lower leg muscles leading to additional knee movement and aggravation of joint tensions? As one example: We tested athletes who desired a more aggressive position. When we asked them how they "felt" on the bike, they asked to go to a lower, more aggressive, position, as they experienced no pain or constraints that they could perceive. However, on a physiological level, with results ascertained through scientific testing, a significant decrease in performance (sustainable output, lactate threshold values, lower VO2 Max values, etc after the proper adaptive time (always important) were evident. The rider "felt" better but performed worse! Over-reliance on verbal feedback from the rider sends the fitter in the wrong direction.

    While it is indispensable to consult with the rider on pathological conditions, pre-existing health issues, equipment used, the scientific method is the only way to ensure precise, reliable, reproducible, and true results. We have proven this with over 10,000 fits done with the CPS in our Expert locations.

    Regarding current methods in use: How do other methods determine the parameters which allow you to optimize the comfort, the power, the efficiency that is indispensable to cycling performance? What measurements are taken, what is the level of accuracy, the reproducibility, etc. and what allows the fitter to optimize the various criteria of comfort, safety, power, efficiency?

    It IS important to understand the individual, to know what needs to be done for his/her unique characteristics, and to apply a physiologically-based methodology and solution to each rider.

    On the surface, the CPS may appear too simple, may lack some "bells and whistles", and may not feature easily digestible sound-bites. It is too complex and sophisticated for that. And, it is the only system that resides in a comprehensive scientific foundation, one that has invalidated many of the misconceptions and suppositions common in the cycling world today.

    Let's look at a couple of the criteria listed above:

    Efficiency:
    Do other systems measure the energetic cost of the cyclist being positioned? If they do, then how and with what metabolic chain device do they measure this? Is this metabolic chain device scientifically validated? Was a second metabolic chain device used to verify the stability and the reproducibility of the measures made with the first one?


    In the testing there may be faulty data or mistakes in machine operation by the person performing the test. How is this faulty data discovered? In watching a rider on a bike placed on a trainer, how can you measure and quantify the improvement of the energy cost? Is it just a question of looking “right” on the bike, for that one or two hours, based on that fit person’s experience?
    For starters, the determination of the optimal energetic position cannot be given during a single analysis (one fit session) anyway.
    The determination of the optimal energetic position requires nearly 8 tests over a 3-month period in order to test the cyclist in a situation of locomotor pattern stability (the new/altered position must have the requisite adaptation time – 600 km’s across all levels; certainly someone who rides more will reach the 600km mark quicker). If not done this way, the variations which you observe will not be directly dependent on the positioning of the cyclist but simply on a modification of the locomotor pattern (position) which deteriorates muscular coordination. Position changes require adaptation time before a determinant on efficacy can be made.
    Comfort: How do you measure comfort in an objective way? What are the parameters which you measure scientifically and what allows for affirmation that the cyclist is in an optimal position for comfort? Certainly looking at the rider on a home trainer during one session of analysis cannot determine if the cyclist is in a situation of comfort. Comfort is directly related to concepts of biomechanics and muscular tension. However, the medical data clearly indicate the respected angles of articular and muscular request in order to avoid all hyper postural requests that would generate arthralgias. In short, the medical community has researched the ranges to which muscles and joints should be subject before negative consequences are engendered. The CPS draws on this.
    Power: What is the good position in terms of power? Is it the one that makes it possible for the cyclist to develop the greatest power? Perhaps, but which power are we talking about? Is it referring to the PMA, anaerobic Pmax, Ppic...? In fact, the “right” type of optimized power depends on the cycling discipline (road, track, tri, etc.). Let us take the case of Laurent Gané, multi-time world champion track cyclist. He was positioned by the CPS in order to develop the largest anaerobic Pmax because he does the sprint and keirin on the track. As a world class athlete Laurent Gané developed Pmax of more than 2600 Watts (during Wingate test) at his best. On the other hand, if you position a Tour cyclist you must seek a position which optimizes the PMA and especially the level of the anaerobic threshold. Indeed, with respect to Tour cyclists, they are not always the cyclists who develop largest PMA which are the best. The best are those who have anaerobic thresholds very high and very close to their PMA.

    Example:
    Individual 1:
    PMA = 500Watts (individual = 70kg), is 7.1 w/kg
    Threshold = 94%PMA = 470Watts
    Individual 2:
    PMA = 520Watts (individual = 70kg), is 7.4 w/kg
    Threshold = 89%PMA = 463Watts

    Attention, even though this is an essential parameter it is not sufficient... Indeed, Individual 1 will not be able to compete with N°2 if his output is not optimal. Thus it is absolutely necessary to correlate the values of power to the threshold, of PMA, of VO2, VT1 (Ventilatory Threshold), VT2, LT1 (Lactate Threshold), LT2... The whole picture must be considered. The short version is that the criteria of performance of HEALTH and COMFORT cannot be analyzed individually during a specific analysis because the modifications measured are only tied to the fact that you changed the position. There is no way to check if the position is optimal because the proper adaptive time hasn’t been given. Moreover, during the analysis of one individual, the risk related to the error of measurement (failure of the material, error of calibration, moisture in sample line...) could not be controlled. In short, the differences in actual values are more likely due to skews of measurement than by a real impact from the new position.
  • While I may feel one particular problem in my riding position, for instance some lower back pain, how does the CPS ensure that the proper issue is being addressed instead of simply looking at what is evident?
    How do you fix the root cause of a problem without causing other problems? The position of a cyclist must be looked at comprehensively, not in an isolated way. For example, many people try to fix hamstring pain by lowering the saddle. Indeed, hamstring myalgia (pains) are explained by a hyper tension of these muscular groups. Consequently these people think that this is explained by saddle height that is too high and which, therefore, aggravates the tightness. This can be the cause but not always. If you think in a more total way, one can also find that this hyper tension is explained by a position that is too laid-out /or with the cyclist too inclined (too long of a reach between saddle/bar and/or too large difference saddle/bar height). Indeed, such a position stretches the hamstrings and can be the root of pains, tendonitis, myalgias. Finally the problem was not the height of the saddle but the reach from saddle to bar. If you want to regulate this problem by lowering the saddle you are likely to cause patellar tendonitis as well as ankle issues because the saddle height is now too low.
  • 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.
  • Does a bike fit change over time as flexibility, strength, body composition, riding style and goals alter? If the CPS is fit to where my optimal position "should be" will that position cause discomfort and at worst, injury? Isn't it better to make small changes incrementally over a period of time, making sure at each stage that I can adapt successfully?
    An individual’s increased physical level during the season will enable him to tolerate different and typically more extreme positions. The tolerance doesn’t mean that the position is correct, though. If that is true from a point of view of comfort (the limit of comfort is extended and the rider can tolerate more during the summer as compared to early spring, let’s say), you must remember that you will generate problems on the physiological level (oxygen transfer, power transfer, muscular operation, amplitudes of optimal work...) without being able to perceive this. Moreover, it is important to understand that a good position does not depend on the point of time in the season... It is not the limit of comfort that determines the proper position; such an approach is incomplete. It is not because the cyclist feels ok that he is well-positioned!
  • How is cleat positioning considered with the CPS? I've seen that some fitters look at the "ball of the foot", others at the area between the 1st and 5th metatarsal, and others something altogether different.
    What's most important to consider is the point of biomechanical interest and the cleat position that is validated scientifically. Currently, all the work of sporting podology applied to the cycling and the biomechanical unfolding of the foot indicates that the point of optimal support of the foot on the pedal corresponds to the axis of the 1st metatarsal. This is supported in elementary plantar biomechanics. If the cleat axis is positioned too far behind the metatarsal you are likely to create acute pains on the level of the former insertion of the aponevrotic plantar (because your zone of support under the foot will compress the plantar muscles). You will also limit your natural lever arm (needed for the proper rotation of the ankle) and, as such, the transfer of power to the pedals. Example: breaking a nut. Try breaking it by pushing on the “ball of the foot” with your naked foot. Then try breaking it by positioning the nut behind 1st metatarsal... You will understand immediately that you will have less force and that you will have sharp pains on the level of the muscles of the plantar aponevrotic!
  • Does the CPS fit method take into account my opinion or feedback on my fit? After all, I'm the one riding with the position!
    Yes , completely in agreement with you. However, there is no established language to consistently describe one’s feelings on the bike. It is important to understand any physical issues/limitations that a rider may have while keeping in mind that most problems are going to be a direct result of the poor fit that they currently have. A newly-positioned rider, even one in the same position for years, may experience some initial muscle pain due to the new position. And, there will definitely be a decrease in efficiency until the muscles have become coordinated properly. But, after being properly fit (with the proper adaptation time to follow), these issues and all prior issues relative to poor fit will disappear. Guaranteed.
  • Knee-over-pedal spindle" using a plumb-bob appears to be the rule in bicycle fit. It's used to find saddle height and set-back because of how it helps position people with different femur lengths. The CPS doesn't use this...why not?
    Firstly, for a given inseam, the variations in the length of the femur between individuals is tiny and negligible in the determination of the optimal saddle height and set-back. Moreover, the length of the femur can only be measured precisely through the use of a body scanner or x-ray. All other methods are imprecise and, therefore, invalid. Medical data specify that the length of the femur = x% height of the articulation of the collar of the femur (value which we precisely measure with the hydraulic inseam jack under constant pressure). Using the plumb line to determine the set-back has no scientific evidence to support it or suggest that it is optimal. It is an antiquated concept developped during the late 1970's before the advent of physiological testing, advances in the medical arena, and modern cycling equipment (including clipless pedals, carbon-soled cycling shoes, new saddle technologies, etc). It was never validated scientifically, as it was developped through a very small study looking at how pro riders were positioned WITHOUT looking at how the riders performed, if they could have performed better positioned differently, and if there were ramifications on the riders' health. Look at the incidence of tendonitis among professionals and the fact that they don't plan on performing at a high level beyond their pro career life-span and you'll see how suspect this idea is.

    Moreover, this concept is only founded on principles of mechanics (lever arms) which optimizes the transfer of force when the crank is horizontal... The human body is not a machine first of all. It is not just a simple skeletal system but is also composed of a muscular system, an articular system, a respiratory system and blood! This entire system doesn't function in a linear method that the "Knee-Over-Pedal-Spindle" approach considers. It is much too simplistic and limited. It does not regard the human body as an ensemble of systems evolving/moving in harmony.

    Some believe that the "Knee-Over-Pedal-Spindle" approach will help find the position that generates "maximum power". The “maximum power” should be required only for a track rider as it speaks only to VERY short efforts that are not based on maximum efficiencies that are demanded in road/cross/mtb/time trial/triathlon disciplines. For these disciplines, you must seek maximum OUTPUT. This requires more than just the application of levers and a mechanical view of the cyclist’s functioning.
  • Flexibility. For those riders who are more flexibile or for those who get more flexibile as fitness increases, is a more aggressive position (i.e. lower bars, longer stem) without any loss of power or efficiency is possible?
    It is not because we are more flexible than one must choose a more extended position or a more “aggressive” set-up. Yes, it is possible that the cyclist feels o.k. while being more stretched-out but this should not determine the good position. The rider is incapable of perceiving what is happening across his/her entire physiological make-up, i.e. the rider cannot see if blood is flowing optimally, and may feel “good” while actually producing a negative physiological effect and net loss in performance/health terms.
  • I sit on the saddle differently than other riders I see. Is this considered?
    Anatomically speaking, all people should sit on the saddle in the same fashion. Yes, we are each unique but our anatomic structure demands that proper saddle position is the same across all individuals. The pelvis on one person may be wider than another and, for that reason, it is important to find the proper saddle width for you. But, the way a rider should sit on the saddle properly is established via evidence from the medical and scientific community. Today, for each saddle there is an optimal zone of support which provides stability for the ischion (sit bones) and improves comfort (without damage to soft tissue or decrease in blood flow to critical areas). However, it is true that the position of the pelvis on the saddle can vary enormously when the cyclist is badly positioned on the bicycle which leads to differences in how a rider sits on the saddle. There will be some slight fore or aft position change when the rider is on the top of the bars, the hoods, or the drops but it is important to limit the deltas between these positions (using a bar that has a reach less than 110mm and a drop less than 170mm). And, it is important to consider which levers are being used (Campagnolo, Shimano, SRAM) as lever lengths change among each platform and can increase your reach by 1.5cm in the case of Shimano!. The position defined by the CPS is based on the zone of support for each saddle make and model and is determined to provide the best stability and least amount of movement while seated.
  • Does the CPS assume that both legs are the same length? Can it address the fact that I may have one leg longer than the other?
    (Please see answer to question 3)
    Also, the CPS does not assume that both legs are of equal length; by drawing upon the vast research and study in the medical/scientific community, we already know that the body is naturally asymmetrical. Moreover, the body adapts to the various asymmetries in order to function properly. Only in pathological cases (less than 0.9% of the population) does a true leg length discrepancy enter the mix. Even so, the focus must be on looking at the individual’s comprehensive case. If the only effort is to look at the leg length without taking into consideration the entire picture then additional harm will occur.
  • How is pedaling style, i.e. heel down/toes down/flat-footed, taken into consideration?
    The only loco-moteur activity that human being does innately is walking. Just like pitching a fast-ball and developing the proper golf swing, the pedal-stroke is a 100% learned action. There is no “natural” way to do it and, as such, the motion and physical coordination can be acquired. There is a proper technique that optimizes efficiency and this is proven using the proper measuring devices, kinematic, and cinematic studies as employed in the foundation of the CPS. Each rider may have a unique "style" in that your knees will move based on the natural predisposition your body has but any different pedaling technique is an error of positioning and poor technique in the pedal-stroke. Example: If your saddle is positioned too high, you pedal with your toes down and conversely, if your saddle is too low you will drop your heel. With a correct positioning of the saddle in terms of height and set-back, you must be able to articulate the ankle in an optimal way. The CPS result guarantees that you will be properly positioned to have the optimal pedal technique.
  • Can muscularly "stronger" riders use longer cranks or get a more efficient position that takes advantage of this strength?
    The strength of muscular groups should not determine the position of the cyclist even if it may influence it. Once again, the position is not summarized with only one concept of what comfort is, or of the amount of force exerted on the cranks... the optimal position of a cyclist must be a comprehensive solution because only this type of approach makes it possible to manage the entirety of interactions between each system (muscular, skeletal, tendon, blood, ligament, articular, pulmonary...).
  • What is the importance of having a flat back?
    (please see question 2).
    Everyone is built differently and trying to get a flat back both not possible and no indicator of being properly positioned. While some riders have anatomic traits that allow for this, it's not a rule to follow. Being able to tolerate a position that is very "laid-out" just to get a flat back does not mean that it is the good position. Indeed, for various reasons certain individuals are able to tolerate a very laid-out position without having problems of comfort. However, these individuals deteriorate their output, their effectiveness, the transfer of power to the zones of transition, limit the blood and pulmonary oxygen circulation, etc....They cannot feel the physiological constraints happening inside their bodies and conclude that they are able to function well while maintaining an aggressive position. The only way to understand the impact is to view the athlete in a comprehensive fashion with “energetic costs” being ascertained as we completed via the CPS research.

    Additionally, the idea of a flat back comes largely out of a visual examination of professionals, who often just look great on bikes. The thinking was that if a pro looks like "x" then all riders must be positioned accordingly to ride better. However, professionals are an anomaly in their ability to assume work-loads, perform, recover, etc. Strictly speaking, they will outperform any "normal" person just because of their innate physical gifts. However, just because they are professionals doesn't mean that they are properly positioned. In fact, most professionals have never been positioned and are not even coached. The average club cyclist has more access to proper training methods and proper positioning. The CPS method will help you realize your potential, providing the right fit to help you perform best as proper coaching and equipment selection is added to the mix.