In this photo the leg spring mechanism of this female weightlifter as in the previous example, releases such that hip knee, ankle and feet bend to redistribute and dissipate the mechanical energy of the body and the barbell. Joints bend, muscles, tendons and ligaments elongate elastically. These same tissues absorb the force of the falling barbell, only to recoil so that the forces are not concentrated in the joints.

It’s All Connected: Part II

Its All Connected

Part II


Andrew Charniga, Jr.©

A logical critique of:

“Rational and Implementation of Anterior Ligament Injury Prevention Warm – UP Programs in Female Athletes”, D. P. Bien, 2011 J Strength & Cond Research 25(1): 271 – 285, 2011

As has been already noted the central thesis of the article which inspired this essay is based on a single, false assumption.

This false assumption is a myth. It is a myth based on a belief that anatomical differences between females and males can predispose female athletes to greater rates of injury in athletic events where females are most likely to participate. American sports where females typically have a higher rate of injury of anterior cruciate ligament are soccer, basketball, volleyball and even softball.

Our premises in diametrical contradiction to that false assumption:
/ there is nothing wrong with the female body;
/ the female body is more complex than the male body;
/ connected with the greater complexity of female anatomy and physiology, females have more sophisticated reactive – protective mechanisms;
/ greater sophistication of reactive – protective mechanisms can translate to a greater potential injury prophylactic; not vice versa.

Problems created by can’t and don’t

“pathobiomechanical, dynamic valgas collapse” (Bien, 2011)

The following statement is based on what the literature refers to as the ‘Q’ angle.

“Recent video analyses also revealed that women had higher knee valgus angles than men did during noncontact ACL injuries, and that dynamic valgus was the most common ACL injury mechanism in female handball and basketball athletes” (Bien, 2011).

Females typically, but not exclusively, have proportionally wider pelvis than males. That means females have a larger angle between the head of the femur and the knee joint relative to the vertical axis. This anatomical “defect” is often cited and purportedly proved to be a mechanism of ACL tears in women because in jumping and landing the forces encountered by the athletes of a wider pelvis, would subject the knee joint to excessive stress.

The knee joints of the female, or for that matter, a male athlete may bow in a so – called “dynamic valgas” (Bien, 2011) disposition to stop or otherwise amortize the body on landing from a jump in basketball, volleyball or other sports. In this case, the focus of the researcher’s attention is the point of injury. Forces calculated at the point of injury are the cause; with the female “defect” (‘Q’ angle) as a predisposing “mechanism”.

A male weightlifter’s knees bow inward in a weightlifting exercise without ill effect. Weightlifting specialists do not consider this some sort defect of the male anatomy. Nor do they assign it some sort of make –  up name like “dynamic valgas collapse”, as if it were a disease. Charniga photo

The following statement encapsulates an astonishingly pervasive idea; ignorance personified. Over time it has formed the foundation for in-numerable false assumptions about predisposition to injury and exercise techniques:

“The tighter the ligament the healthier the knee.” (Karl Klein, 1962)

This stupid idea, in one form or another is widely accepted in the academic and medical communities of the USA. Basically, it means ligaments connect bone to bone. Consequently, to hold a joint together, to maintain stability, ligaments must form a tight bond; otherwise, in the case of a hinge joint like the knee, there will be movement outside what is believed to be an acceptable amplitude of motion in straining, or amortizing an athlete’s body on landing, switching directions in sport exercises, and so forth.

The female ‘Q’ angle defect is thought to be a root cause of the disproportionate female injury rate because of a valgus shifting, i.e., the knees shift towards each, ala a knock knee disposition. This shifting of knees is believed to stretch ligaments and/or otherwise inflict excessive stress on the ACL ligaments.

For instance, the idea “a tight ligament is a healthy ligament”, (K. Klein, 1962) morphed further into the academic community. Consider the following quote from a standard Kinesiology textbook:

avoid forcing the knee joint into extreme flexion… this may weaken ligaments and other structures in the joint” (Luttgens, 2002)

According to Luttgens (2002) extreme” bending can “weaken ligaments and other structures”. No attempt is undertaken to explain how stretching ligaments would weaken them; and, no concrete or practical evidence to support such a claim. Furthermore, the weakening and damage the author is talking about only refers to the act of bending itself; without even considering the effect of additional forces involved in deceleration. In this example, a falling, heavy barbell, “forces the knee joint into extreme flexion”. Charniga photo

In her university standard text, Kinesiology professor Luttgens, passes on the idea tight ligaments are healthy. She proceeded to pass along false information, based on a false assumption; because in the words of Thomas Paine “a long habit of not thinking a thing wrong, gives it a superficial appearance of being right”.

In this example, the academic community assumed if the research says fully flexing the knee joints is bad, it must be true. No reams of evidence, certainly no practical experience can be found in these texts to support such an assumption.

This false assumption about tight ligaments has been around at least since the early 1960s. Consequently, it has been passed down through textbooks; including updated revisions; passed on through innumerable word of mouth communication, such that, few question it. Those who “know” these things about tight ligaments, don’t even know whose idea it was, where, or how it started. {see references #36: Bill Starr’s letter of 1963 to Strength and Health}

The fact that this idea defies logic is not a question that is raised; so many people, especially academics, athletic trainers, doctors, physical therapists and so forth, assume it to be the truth. By not questioning it they accord it in the words of Thomas Paine, a “superficial appearance of being right”.

Now consider another statement from the guy who deserves discredit for starting this madness:

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

Here we can see the underlying basis from which follows the original false assumption that a tight ligament is a healthy ligament. If tight is healthy, then bending further than what is perceived to be necessary, what is believed to be acceptable, will stretch the ligaments making them unhealthy. It can even, according to kinesiology professors, “weaken” the ligaments.

Taken a step further, the tight ligaments are healthy line of thinking proceeds to the next illogical step:

“…. in Klein’s view “anything below a half knee bend,” he says glumly, “is useless and ruinous.”

The profound stupidity of this remark, not to bend any further than a half bend because it is ruinous; from which the author of this essay, in a manner of speaking, got directly from the horse’s mouth (personal communication with K. Klein, 1982); not only precludes reasonable participation in sport, but a lot of activities of daily living.

This “superficial appearance of being right” idea of course is then adopted by other academics.

“The demands placed on the muscles and ligaments of the knee joint during deep squats are severe.. A much safer alternative (to deep knee bends) would be the half squat exercise”. (Luttgens, 2002)

The statement taken from Luttgens’ well – respected Kinesiology text, reflects the assumption, if someone researched knee bending and decided a half knee bend is safe, it must be true. Consequently, the author proceeded to communicate this non sequitor to students through university approved textbooks; and, presumably lectures, prompting countless word of mouth repetition. So, even though this is a lie, it becomes a false truism, because so many people believe it.

This is how an assumption, “not thinking a thing wrong”, works its way into the mainstream. Somebody with university issued initials after his/her name says don’t bend too far it will stretch and weaken ligaments, so it must be true. Students pay tuition to receive credit to absorb and regurgitate stuff like this; not to question it.

According to this line of thinking, were any truth in those statements sports where the athletes bend through a large amplitude of motion such as weightlifting, hockey goalies, catchers in baseball and so forth would certainly be injury prone; at the very least walking around with unhealthy joints. Athletes participating in those events would be stretching ligaments, weakening them; which of course is unhealthy.

Now consider this:

“An athlete is said to possess optimum flexibility when his range of motion exceeds somewhat, the amplitude of the competition exercises. This so – called “flexibility reserve” (it is more precise to say the “extensibility reserve”) allows one to reduce the stretching resistance of the muscles within a given amplitude of movement to the minimum; consequently, the exercise is executed without superfluous tension, i.e., more economically. Furthermore, an extensibility reserve is a safeguard against injury.” R. Moroz (1980)

Soviet sport scientist Roman Moroz’s concept is the dialectic opposite of K. Klein and his legions of unfortunate disciples. This concept stipulates an athlete should cultivate a larger range of motion in joints than is required for a given sport; for two important reasons:
/ a larger than required amplitude of motion in joints translates to less “internal” resistance to movement, i.e., less power is required because of less resistance to movements encountered from muscles, tendons, ligaments, fascia;

/ a larger than required range of motion in joints can be an injury prophylactic, i.e., forces can be better redistributed, even dissipated through the elastic soft tissues enhancing reflex mechanisms to protect joints.

“Our research supports the existence of reflexes to protect joints” (F. Zajac, 1993)

MAtam Crumple
 In this example, an extensibility reserve, i.e., more mobility than is required in performing the exercise; makes this situation, which would most certainly result in injury, a non – event. The hip, knee and ankle joints bend reflexively, as one; elastic tendons and ligaments, stretch and recoil. After the weight fell on him the lifter simply got up and walked away. Charniga photo.

An example of strength training an elite athlete for an event (downhill skiing) by bending in such a manner within a stipulated range of movement which conforms close to the range of motion at hip, knee and ankle the athlete encounters in skiing. In this example the athlete performs half squats with significant leaning forward of the trunk, toes pointed straight ahead with shins almost vertical. The exercise depicted for an elite skier is designed for hip, knee and ankle to bend artificially in line as if all three were simple hinge joints. Strength training of the lower extremities in this manner is a disaster waiting to happen. Irrespective if a skier encounters conditions similar to this posture in skiing, or not; those conditions are not constant. 

What does all this have to do with the valgus argument as the mechanism of ACL injury? The underlying assumption from the highly questionable research cited by Bien, is that shifting of the knees towards each other on landing, or otherwise straining in a bowed knees disposition, reflects an inherent flaw in the female organism. And, it is this wider than a male pelvis defect, with a so – called larger ‘Q’ angle that is purported to be a mechanism for ACL injuries.

The foundation of this argument originates from old ideas fostered in academia. In this case, the researchers assume bending outside the confines of what is considered safe, stretches ligaments such as the ACL. Stretching ligaments is dangerous, hence their conclusion the “mechanism” of ACL injury is the different – from – a – male female anatomy which can subject the knee ligaments to stretching. This stretching is due to the proportionally wider female pelvis and insufficient control of this movement within what the researchers believe to be acceptable parameters. 

Reverting to the statement “differences have been identified throughout the trunk and lower extremity” (Bien, 2011), we can see this bias clearly follows from the underlying assumption started by K. Klein, that stretching ligaments is bad and can lead to injury. Why do more females suffer disproportionally more ACL tears? The female skeleton is different; knee joints can shift through a larger range of movement. Consequently, according to experts stretching ligaments can weaken them, resulting in injury. This is what this body of research proves – the underlying bias; however improbable that may be.

Our examples of weightlifters whom did not suffer injury as a consequence of some fall or mishap; but, according to the thinking commonly expressed in the research of ACL injuries, should have been injured, is a completely different approach; a diametrically opposite concept. This approach, in effect, is a conceptual form of reverse engineering to gain insight into the complex problem of sport injury.

The question that begs to be asked: why don’t these weightlifters who fall, twisting muscles, joints, ligaments and tendons, with huge weights bearing down, suffer serious injury? In point of fact, why are the overwhelming majority falls like this non – events? Whereas, female ACL injuries incurred running up and down basketball courts, soccer fields, jumping and moving about volleyball courts and so forth are so common in the USA, hundreds of papers have been devoted to this problem?


 The contortion of the young woman’s lower extremities in falling forward with a heavy barbell on her chest is magnified when she drops the weight on her extended legs. Despite what would appear to be a disaster; the athlete simply walked away to get ready for the next lift. There were no adverse consequences. A fall like this should certainly result in knee, ankle joint, tendon and ligament damage if tight ligaments were indeed “healthy”. However, the body’s natural protective reactive mechanisms kick in to prevent injury. Charniga photo

If tight ligaments are healthy, all the bending; the forced stretching of the body’s soft tissues all the while lifting huge barbells, inherent to a maximum effort sport like weightlifting; should produce significantly higher rates of ligament tears, especially among female lifters. But that is not the case.

Moreover, how is it that young, healthy, mostly American female athletes tear ligaments participating sports with significantly less stress on the body than is commonly encountered in maximum sports like weightlifting?

The underlying basis of the research cited in this article is an assumption the higher incidence of ACL injuries in females is due to physiological deficits of the female body. What about reverse engineering this false truism to other sports?

For instance, a recent study of elite female and male track and field athletes concluded:

“Sex is a risk factor for injury during athletics championships. It has been reported that male athletes suffered more injuries than female athletes during previous World and European outdoor championships”…..

“The overall incidence of injuries was significantly higher in male than female athletes (110.3±6.8 vs 88.5±6.7 injuries per 1000 registered.” (E. Pascal, et al, 2015)

There are several interesting considerations from these findings:

/ perhaps elite female track and field athletes do not move about in a “pathobiomechanical” manner, nor suffer “dynamic valgas collapse”; or, in all likelihood, there are no such things;

/ since the American literature cited is littered with female physiological defects as a mechanism of injury, one would anticipate more female injuries from elite sport events, because of the risk associated with high power output, maximum effort events;

/ perhaps the anatomical differences between the sexes predispose females to lower injury rates in high intense elite sports;

/ perhaps there is something inherently wrong with the male body to be the cause of the disproportionate injury rate to elite male track and field athletes.

The fact the subjects of this study were international athletes is significant. In all probability, because American ideas of tight ligaments, half bending, ‘Q’ angle disease, valgas collapse,  and such, have not infected the culture of training foreign athletes.

Considering the last point, it is interesting to note that other research from the USA, unrelated to sport, happens to agree with the prevailing bias. For instance, a study of female injury rates in the USA military found higher injury rates for females because the authors believed they were predisposed by anatomical and physiological differences between the sexes:

“The authors emphasize that, anatomically and physiologically, women are not the same as men; lower extremity biomechanical differences between men and women may account for gender differences in training injury rates. Women have increased pelvic width, forefoot pronation, heel valgus angulation, pes planus, external tibial torsion, and femoral anteversion. Additionally, because of the estrogen influence, women have less lean body mass and greater ligamentous laxity.

“The combination of anatomy and physiology appears to predispose women to a higher risk of pelvic stress fracture and anterior cruciate ligament (ACL) tears. The diagnosis of pelvic stress fracture has been reported as 1 in 367 female recruits, compared with 1 in 40,000 male recruits, and rates of ACL ruptures for female athletes range from 2.4 to 9.7 times higher than in male athletes.” (B. Springer, et al 2011).

Since the authors repeated, verbatim, the above litany of defects later in the report, to further emphasize their bias; the only logical conclusion to draw from this is that military service is not for women and that their participation is a burden on the tax payer.

In reality, the injury rate from physical training in the military is high because the US military does a lot of stupid things training troops; regardless of sex.

For instance:

“In fact, the primary health threat to troops for more than two decades has been common muscle, joint, tendon/ligament and bone injuries like knee or back pain that are caused by running, sports and exercise-related activities such as basketball and weight-lifting. These activities are not just a primary cause of injuries in stateside locations, but also in deployed locations.“Non-battle injuries resulted in more medical air evacuations from Afghanistan and Iraq than battle injuries,” explained Keith Hauret, an epidemiologist at the U.S. Army Public Health Command, or USAPHC. “The leading causes of these non-battle injuries were physical training and sports.” {Veronique Hauschild, 2015}

Sport specific study of knee injury rates in weightlifting is of special interest considering there is no actual connection between ACL injuries and female athletes. One study found knee injuries in weightlifting at the same rate as dance, corresponding to 1 – 4 per 1,000 hours of training; significantly lower than sports such as handball, American football, combat sports  and ice hockey. (Urso, Voglino, 2015). 

The medical committee of the European Weightlifting Federation recorded injury rates, sexual differentiation of injury inclusive, of the European Weightlifting Championships from 2002 – 2009:

“Compared to a statistically significant number of cases (about 3,500 participating athletes), once again the data related to knee injury are very low in men, and completely absent in women, despite the stress generated in such a high level of competition.” (Urso, A., Voglino, N., 2105) 

The significance of this survey is the lack of preconceived bias as a governing factor; which is patently obvious in the research that serves as the foundation of the Bien paper and the study of female injuries in the military. And, it is curiously in agreement with the survey of Track and Field injury rate between the sexes: men are more predisposed to injury in high intensity elite sport.

Is it a coincidence, studies, or otherwise research clouded by preconceived false notions, just happen to produce results confirming the underlying bias?

Consider this quote:
“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)


This 2009 photo of a female weightlifter’s knees touching in mid – strain; including a significant tilting of the shins inward. This disposition of shins occurs during the period of the largest strain, i.e., the valgus position of the knees which the literature says is likely to result in ACL damage. Charniga photo.


The same athlete training in 2010. Assuming a yearly training load of approximately 20,000 lifts of the barbell counting only lifts of at least 60% of maximum; this young woman would have taken approximately five – seven years of training to reach the level to compete in the National Games in 2009. Adding the next year’s training and that required to make it to the 2012 National Championships (where she competed) this athlete had done something in the neighborhood of 180 – 200,000 lifts of the barbell in her career. She trained and competed all the while with, in the words of Bien, “dynamic valgas collapse” and pathobiomechanical motions. Charniga photos. 

Even if special control of movements were a viable option especially in sports where high level coordination, speed of movement and reactivity are paramount; nothing would have altered the underlying basis for this approach which stipulates, there are many things wrong with the female body. Because all of these structural defects would still be present; special neuro – muscular training, or not.

According to the ACL research and the author’s (Bien) assertion, strengthening the gluteus maximus and medius strength and “control” of “pathobiomechanical hip motions” can be a preventive measure for ACL injury in women. So, the idea is that these muscles are weak and the female athlete needs not only to strengthen them but also to “learn” to control the action of these muscles; which in turn, well help to alleviate the disease known as “pathobiomechanical motion”.

That being said, consider the following:

/ none of the examples of weightlifters presented, or for that matter, weightlifters in general, male and especially female, who are bowing their knees inward while straining to lift, have weak hip muscles;

/ many muscles participate to flex and straighten the lower extremities; for instance, the single joint adductor muscles of the thigh whose tendons do not cross the knee, participate in straightening the thigh (Tesch, 1993). Consequently, the inward bowing of the knees can be a reflection of these muscles contracting to straighten the thighs; and, of course dissipating forces on landing or switching directions;

/ training an athlete to control actions of hip muscles to keep lower limb movements linear, which is the goal from the misguided research cited, is unfeasible and probably dangerous for dynamic sport, especially dynamic sport involving fast, reactive movements.

As noted, the focus of the research cited in this article  centers around proving female anatomy is both defective for sport and the principle causation of the sex differences of rate of ACL injury between American male and female athletes.

Consequently, it should not be surprising the paper devotes almost nothing to the tendons, ligaments and musculature of the shin, foot and ankle joint as a source of causation or necessitating special training.

“A muscle may act to accelerate the joints it does not span as much or more than the joints it does span”, i.e., the soleus acts to accelerate the thigh clockwise as much as it does to accelerate the shank counterclockwise.” F.E. Zajac, 1993

38Muscles of the rear of the calf contribute to shifting the shin from a tilted forward (bent knee) position to a vertical disposition. The soleus and other single joint calf muscles are synergistic knee extensors, i.e., muscles located on the rear of the shin accelerate thigh and shin and of course, straighten the knee, by a process known as inertia coupling (Zajac, 1993, 2002; Bobbert 1986). These muscles work in concert with the quadriceps muscles and with single joint adductor muscles to straighten the knee joint. Moreover, these muscles of the shank, likewise, amortize knee bend, shock absorbing  and dissipating forces on the lower extremities.  Charniga photo.

Instead, the research follows the line of thinking consistent with preconceived bias: ideas of insufficient of female hip and pelvic musculature, hamstring insufficiency, core strength, insufficient coordination of movements and the like which one can find for sale at national conferences attended by personal trainers, physical therapists and so forth, i.e., vendor data.

Curiously, the very end of the paper briefly mentions mobility of the ankle in shock absorption; but, nothing about how the musculature of the shin, participates to bend and straighten knee and trunk even though these muscles are interconnected from  foot to hip joints. Another important flaw in this line of thinking is to try apply classroom memorized concepts of musculo – skeletal anatomy to the real world movements of the human body’s 600+ muscles and 206 bones.

For instance, one of the bizarre exercises presented in the article to strengthen hamstrings is illustrated with two pictures of a shaved head, apparently obese, white male standing on the feet of a female holding a strap attached to her back as she bends at the knee, lying face down towards floor. Is this supposed to be science; bondage maybe?

For the record, of the four parts of the hamstring group, three cross two joints, which means they cannot be classified as either purely flexing or extending muscles (Bobbert, 1986;88). In point of fact, three fourths of the hamstring group function as effective transfer straps along with the gastrocnemius to transport power from hip to foot and redistribute the force of ground contact on landing from foot to hip (Bobbertt, 1986; Van Ingen Schenau, 1989: Prilutsky, Zatsiorsky, 1994)

How this silly, I saw it at a conference, make – up exercise, can possibly translate into an injury prophylactic; cannot be ascertained, because athletes do not encounter those static conditions in sport where the two – joint hamstring muscles work in this fashion to generate power or redistribute mechanical energy.

A number of aspects presented in this article for the most part make this sort of research worthless; because of underlying bias and/or misdirected focus:

/ the female body is inherently more susceptible to injury in sport than a male because of biomechanical and physiological differences;

/ the idea that stretching ligaments is dangerous;

/ the idea to control bending of the lower extremities within an amplitude of movement arbitrarily considered safe;

/ the focus the hip and trunk, hamstrings to almost excluding the role of the muscles tendons, ligaments of the feet and ankle play amortizing force on landing and rapid change of direction in sport;

/ the prescribing of simplistic exercises based on textbook anatomy without consideration of the interconnection, inter-condtionality and interdependence of all the body’s muscles tendons and ligaments to perform sport exercises;

/ the absence of any semblance of curiosity to consider reverse engineering causation of ACL injury rates in females with respect to other sports.

In part III, another aspect of ACL injury causation deserving of serious consideration will be presented. The role of the muscles, tendons and ligaments of the ankle and foot may be the single most important underlying mechanism of the relatively high rate of injury which occurs under the relatively modest conditions of strain in sports like basketball, volleyball, soccer and so forth; when compared to maximum strain sports like weightlifting and track and field.



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