A Stability/Instability Convexity

Andrew Charniga


“There are some ideas so wrong that only a very intelligent person could believe in them.” George Orwell

Various essays (Charniga 2015 – 2020) have dealt with injury susceptibility in female weightlifters; misinformation about the injury susceptibility of female athletes in American sports;  peculiarities of a ‘feminine expression of strength’ in weightlifting exercises; features of unique warm up protocols of some elite female weightlifters and problems with the female weightlifting barbell.  Many instances where cited of terribly flawed science emanating from academia; unfortunately managing to make its way into the mainstream. In most cases the foundations of this pseudo – science are based on false assumptions.

Generalizations of differences in injury susceptibility between male and female athletes; for instance, paradoxically centers around two everyday words: stability and instability. 

There is nothing ominous about either word, especially stability; the definition of which generally has positive connotation. However, it is the manner in which these words are deployed in the literature of sport injury; at best are opaque. What is stability and what makers it a valuable quantity? Why and how is instability ascertained a negative quantity?  

Figure 1. Super elite female weightlifter lifts with shifting outward (varus) disposition of knee joints relative to hip and ankles. Charniga photo.


Figure 2. Super elite female weightlifter practically touches knees together in struggling to stand from the squat, i.e., a large valgus shifting. This shifting is referred to as a deformity. Charniga photo

Safety Evolved From Necessity

One finds the term stability repeated over and over in reference to athletic injuries and rehabilitation; such that, it has no concrete meaning. This word and its antonyms instability, unstable and others of similar syntax; such as fluctuation; seem to be everywhere in kinesiology related papers, doctor, athletic trainer and PhD talk; when the topic is injury; all the more so, in reference to the injury susceptibility of the female athlete.

Two of the most common definitions of the word stability are: “the quality or state of something that is not easily changed or likely to change; the quality of state of someone who is emotionally or mentally healthy” {Merriam Webster}.

Synonyms for stability/stable  include firmness, strength, sturdiness, soundess and the like. Antonyms of stability {instability} are unstable/unsteady, emotionally unhealthy, inconsistent, insecurity and so forth. There is an obvious positive connotation associated with someone or something that is stable; whereas there are negative implications for someone or something that is unstable.

Not infrequently, unstable/instability appear over and over in the literature of injury susceptibility of female athletes, i.e., negative denotations of difference according to sex.

According to the doctrine of Confucius, femininity is Yin and masculinity is Yang. For the most part traits defining femininity or Yin are negative; whereas defining traits of masculinity are positive.  Not surprising, there are many present day parallels with Yin (femininity) defined in terms of instability and Yang (masculinity) defined in terms of stability, i.e., female negative, male positive.

Frequently, the antonyms of stability are applied to injury susceptibility of athletes of both sex; just more often to females by means of differentiation by sex; in concert with such designations as laxity, fluctuation, loose, inconsistent and so forth.

Medical, academia and rehabilitation professionals typically view stability/stable in a  positive light; a goal to achieve, i.e., something that is good; it lies within the purview of their understanding of human physiology and rudimentary comprehension of biomechanics.

Consequently, when the subject is ‘allowable’ movement in joints, extensibility of tendons and ligaments; the syntax they employ denote positive connotations such as stable, stability, tight, firmness and the like. On the other hand, antonyms commonly applied to the same carry a negative connotation: instability/unstable, lax, laxity, weak, fluctuate, loose, random, and the like.

For example, the following quotes from the literature can be fairly representative of the state of academic ‘pseudo science’ in so far as the realm of female athletes and injury susceptibility; not just devoid of fact; outside of reason: 

1/ “Neuromuscular training can significantly increase dynamic knee stability in female athletes. Hewett, T.

2/ “Oral contraceptives stabilise hormone levels during the menstrual cycle and may function to either passively or actively stabilise the knee joint.” Hewett, T.

3/ “It’s likely that oral contraceptives help maintain lower and more consistent levels of estrogen and progesterone, which may lead to periodic increase in laxity and subsequent risk of tear (instead of periodic ACL weakness),” explained lead author Steven DeFroda, MD.

4/ “Female sex hormones (i.,e., estrogen, progesterone and relaxin) fluctuate radically during the menstrual cycle and are reported to increase ligamentous laxity and decrease neuro-muscular performance; And, thus: Are a possible cause of decreases in both passive and active knee stability in female athletes”. Hewett, T.

5/ “NBC Evening news 04-15-09 Robert Bazel reported that: “Studies show female athletes are 2 – 6 times more likely to suffer ACL tears. One possible explanation is hormonal. The female estrogen latches on to and weakens the ACL.”

6/ “The ability to assist in control of dynamic valgus collapse at the knee makes addressing gluteus maximus and medius strength and control imperative in a training program for ACL injury prevention. Targeted training of the gluteus maximus and medius may assist in control and reduction of pathomechanical hip motions and postures placing the knee in at-risk.” (Bien, 2011)

The first statement is of course is oxymoronic: a combination of contradictory or incongruous words (such as cruel kindness). The second and third are simply incomprehensible gibberish.The fourth and fifth are the most outlandish of all and should be the poster child for the entire spectrum of pseudo – science surrounding the female athlete. Would it be a waste of time to point out endogenous estrogen; an integral part of male physiology; apparently doesn’t weaken their ligaments?  

The sixth statement is voodoo biomechanics.

At any rate, all the above statements of ‘experts’ are all typical of the pseudo – science encompassing the subject of sport injuries in the western literature as it pertains to women. That educated people actually believe these things can be expressed by the Tertoyllian/Votaire dictum:

Credo quia absurdum est {I believe because it is absurd} Tertuyllian/Voltaire

The unfortunate underpinnings of a false belief; for no reason other than “because it is absurd”; are the solutions to problems the believers pull from the hat; like so many rabbits. For instance, to mitigate the acknowledged, prolonged rising incidence of ACL injury in female athletes; especially young female American soccer and basketball players; the solution is to apply some man made alterations to an entity not made by man.

According to the literature, ACL tears can occur from turning manoeuvres, landing and the like when the femur – shin alignment is bowed inward (see figure 3) or outward.   

Figure 3. Nonsensical examples of bending at knee and hip supposedly predisposing athletes to ACL injury. Note the lack of bending in foot on the right, i.e., the ankle joint does not bend in tandem with the rest of the leg.

A Credo quia absurdum este solution :

“Players are trained to avoid excessive dynamic valgus of the knee and to focus on the‘‘knee over toe position’’ when cutting”. Hewett, T.

‘Teaching’ athletes to run and especially turn with linear alignment of thigh and shin; and, by all means, avoid the bowing in or out of knees while cutting or otherwise making turns as depicted in figure 3; is unrealistic. This is pseudo – science out of touch with reality. The long bones of thigh and shin are connected between multi – planer joints which permit large degrees of freedom of movement. 

To expect any athlete to move about with the thigh and shin in a linear alignment in running, bending and so forth on the athletic field is unrealizable; given that two of the three  main joints of the leg (hip and ankle) are essentially ball and socket and designed to facilitate movement outside a linear alignment of shin and thigh. To assume the slight deviations from a linear alignment as depicted in figure 3 would make man or woman susceptible to ACL injury does not fit in any logical way the evolutionary make up of the human body; let alone the possibility of safely participating in sports where, cutting and turning are mandatory. 

Furthermore, given each foot has 33 articulations; this many millenia ‘evolved intelligent design’ is constructed for complex movements such as pursuit and avoiding pursuit.

Chasing animals for food; and, of course avoidance of capture by larger faster predators are also part of human evolution; they are innate adaptations:

“Animals that feed on mobile prey have evolved a repertoire of anatomical features and behavior strategies to maximize capture success (Lima, 2002), matched by prey in an evolutionary arms race in their attempts to avoid capture (Randall et al., 1995; Walker et al., 2005; Cortez, 2011)”.

The lower extremities are not man made; hence not in need of man made corrections to adjust mobility. Adaptations evolved to manoeuvre effectively to capture prey and/or avoid capture are essential and not in need of man made tinkering. Mobility of joints in the lower extremities, especially redundant degrees of freedom of movement; are built in safety mechanisms as well.

With that in mind; consider the list of injuries compiled by the medical commission of the European Weightlifting Federation in table 1.

Table 1. Injuries incurred at European Weightlifting championships (2007 – 2012). Data of Dr. D. Doerr; from https://www.iwf.net/

Site of Injury








C – spine




































Lower Limb
















The compilation of injuries presented in table 1 are for weightlifters of both sexes who participated at the European weightlifting championships over a span of six years. Several features stand out. The relatively low injury rate for both sexes; a higher rate for males 3.6% vs. 2.5% for females. There were a total of only 3 knee injuries out of 1,414 participants over the six year span; this despite the fact that weightlifting is a sport of maximum strain. Furthermore, the lower extremities, especially the knee  and ankle joints, are subjected to a disproportionate and huge loading in weightlifting.

Even more striking is the fact there were zero (0) knee injuries among the female participants (480 athletes). Ankle injuries are so rare in weightlifting; despite the massive loading on these joints; the doctor compiling the incidences did not bother to allot a column for ankle injuries; even to mark a zero in it.

Why is it the ‘experts’ such as those quoted above do not deem it useful to analyze the injury incidence of other sports in comparing female to male injury susceptibility; especially, considering the outlandish; nonsensical pseudo – science solutions that the ‘experts’ put into print?

Figure 4. Football player loaded down with ‘protective’ wear to restrict movement: knee braces and shoes taped to ankles. Football is a sport of terrestrial – predator – pursuit of prey and avoidance of capture. The lower extremities of the athlete pictured may be  prepared for restricted linear movement. He is ‘prepared’ for linear movement; despite the fact the only straight lines in football are the lines drawn on the field.  

Figure 5. Examples of redundancy in the musculoskeletal system. Female on the left re – bends knees relatively early in the pull portion of the exercise; with ankle muscles to  re – distribute the loading from the back and hamstring group as depicted by the male on the right who has continued to straighten the legs. Unlike textbook oversimplifications of agonist/antagonist (hamstring to quadriceps) strength ratios; one can see females can opt to perform bending straightening movements with other muscles than solely hamstrings and back muscles; and, as such man made alterations are not needed.  Charniga photo

Man is not ‘Man Made’

The single, most glaring false narrative encompassing the stability/instability convexity are that most solutions offered to prevent injury are man made alterations to a non man made entity: the human body. Range of motion in joints are deemed stable and/or unstable, arbitrarily without basis in fact; words such as laxity, loose and the like are tossed about indiscriminately to justify restricting motion; or, the use of inane special exercise techniques. Words like stability/instability fly about so flippantly they are meaningless. For instance, if the words ankle stability {instability} which appear in one form or another 48 times from the paper listed in references by Kaminiski et al, were excluded – there would be nothing of substance left. 

Man – made – modifications to correct movement of hip or alter hormones as noted in the quotes above; are based on the assumption nature is in error in the design of the human body; hence, stability solutions are needed to correct instability of design and function.

Furthermore, another perfect example of voodoo biomechanics is the quote below about knee bending in sport. This was a justification, which continues to this day; for limiting bending to that range of motion in joints most typical of sports like, football, basketball, soccer and so forth. If it seemed reasonable in 1962; few stopped to ask what happens when an athlete falls, slips, etc; when more flexing of lower extremities will come in handy to dissipate or otherwise  re-distribute mechanical energy to prevent injury.

“The deep knee bend bends the knee far more than any athlete ever does…” (K. Klein, 1962).

Redundancy is Stability

A word terribly difficult to find in the literature about etiology of injury in sport; is redundancy. Essentially redundancy means more than necessary; and, as such it would seem to have an ambivalent connotation; out of place in human biology.

Redundancy is expressed often in the literature; in negative semantics; just spelled differently: laxity; lax; loose; fluctuations; unstable; unsteady; insecurity; weak. In the context of injury susceptibility in sport; the use of those negative semantics are very commonly applied to the female athlete. Stability of joints and ligamentous attachments, understood to signify …”something that is not easily changed or likely to change” are positive states which excludes movement outside arbitrarily determined ranges of movement. These ‘outside’ movements are deemed unsafe because “more than necessary” or any redundancy is considered negative.

Figure 6. Bending with large flexing of hip, knee and ankle joints  in squatting (cleaning) subjects the ligaments and the knee joint to less stress (shear strain); in addition to the redundancy factor of absorbing the additional inertia of the barbell. Charniga photo

However, the ambiguous redundancy has mostly positive connotations with respect to engineering and other fields of endeavor: it connotes more than one system, or a back up, in the event one fails. Many positive examples of redundancy can be cited, such as commercial airlines have back up electrical systems in the event the main one fails; critical in an era of fly by wire technology.

Along those same lines, the human body has radial symmetry: two arms, two legs, two eyes, etc. Furthermore, natural selection evolved a bilateral nervous system with contra – lateral control of the human body. Nerves from the central nervous system cross at the mid-line; the right side of the brain controls the left side of the body and vice versa. Conceivably, this could be construed as a back up accommodation: in the event of stroke only one side of the body is affected. Were a linear make up of nerves from the brain to the rest of the body; a CVA (cardio – vascular accident) would otherwise be catastrophic.  

Figure 7. The human body has an evolved bilateral nervous system with contra – lateral control of motor functions: “afferent and efferent pathways cross the mid-line of the body”, Rogers, et al, 2013. Even if the human body were of perfect radial symmetry and muscles from each side of the mid – line were in perfect balance; a balanced outcome of muscle force is not a certainty. Charniga photos. 

In point of fact, the human body, a miracle of biological engineering, has significant redundancy; innumerable combinations of potential muscle action are possible in even a simple flexing and straightening of the knee. This concept is difficult if not near impossible to ascertain in textbooks and such. 

Furthermore, from the academic viewpoint of inane ideas to control and/or restrict joint movement and other preposterous factors such as control of “radical fluctuations” of female hormones; so often stated in terms of stability, or in effect, the attempt to achieve: “the quality or state of something that is not easily changed or likely to change” are exercises in a fallacy of logic. These are, in the words of George Orwell “… ideas so wrong that only a very intelligent person could believe them”.

In point of fact, the utter failure of these ideas to arrest control of female hormones; restrict movement of lower extremities to a linear alignment and the like, is clear from the injury ridden nature of American sports with an abundance of personal trainers, athletic trainers, doctors, conditioning coaches, academics toeing a line of a false narrative; via a single word: stability.

The redundancy of the human body is in fact a safety feature built in by natural selection; absent any need for modifications to achieve some man made condition of stability.

“You get pseudo-order when you seek order…..”. Nasim Taleb

Dynamic sport is a non – predictive; tripping, falling, tackling situations in games vary. Hence, teaching someone to run or bend with linear alignment of lower extremities is unsafe. Redundancy of movement possibilities, especially more amplitude than  necessary for a given sport is in fact safe. Consequently, teaching someone to restrict bending of joints in strength exercises ignores the built in safety mechanisms of redundancy of movement amplitude and multi -planer potential of the same.

Attempts to define stability in order to prevent  instability: has seen the rate of female ACL tears continue to rise even though the so – called prevention procedures  have been around for more than 20 years (3). Consequently, newer, even more preposterous solutions such as issuing birth control pills to juvenile females to protect them from their  estrogen attacking their ACL ligaments (3) have surfaced.

So, we should replace of the meaningless and debilitating concept of  stability; with the solution of cultivating redundancy; because sport is ‘non – predictive’ (Nasim Taleb); rapid, un-choreographed, large and mostly unrestricted movements are necessary to avoid injury and perform in complex sports.  This concept is in stark contrast to the preposterous man made solutions outlined above to stabilize hormones and other attempts to essentially run rough shod over nature.


/ Charniga, A., “Its all connected:part I” and Part II. www.sportivnypress.com

/ Charniga, A., A De-masculinization of Strength, Sportivnypress, Livonia, Michigan 2012.

/ Wilson, R., et al, “Mass enhances speed but diminishes turn capacity in terrestrial pursuit predators, eLife 2015;4:e06487 doi: 10.7554/eLife.06487

/ https://bone.imedpub.com/acute-achilles-tendon-rupture-from-cross-fit-training.php?aid=6701 

1/ “Anterior Cruciate Ligament Injuries: Diagnosis, Treatment, and Prevention” LaBella, C., Hennrikus, W., Hewett, T., Pediatrics May 2014, 133 (5) e1437-e1450; DOI: https://doi.org/10.1542/peds.2014-0623

2/ “Non-contact ACL injuries in female athletes: an International Olympic Committee current concepts statement,” P Renstrom, A Ljungqvist, E Arendt, B Beynnon,T Fukubayashi, W Garrett, T Georgoulis, T E Hewett, R Johnson,T Krosshaug, B Mandelbaum, L Micheli,G Myklebust, E Roos, H Roos, P Schamasch, S Shultz, S Werner, E Wojtys,L Engebretsen: BJSM.bmj.com 11-26-2017

3/ Staff, “oral Contraceptives could be protective against ACL injuries in female athletes”, https://www.uspharmacist.com/article/oral-contraceptives-could-be protective-against-acl-injuries-in-female-athletes/preview/uspeditorial?utm_source=TrendMD&utm_medium=cpc&utm_campaign=US_Pharmacist_TrendMD_0

/ Kaminski, T., et al, “National Athletic Trainers Association Position Statement: Conservative Management and Prevention of Ankle Sprains in Athletes”, J. of Athletic Training, 48(4):528-545:2013

/ Zajac, F.E., “Muscle Coordination of Movement: A Perspective”, J. Biomechanics 26:suppl1:109-124:1993