How czech people grow

14 / 06 / 2011
How czech people grow

If you feel that your children grow over your head then you may not be far from the truth. As was confirmed by routine measurements, Czech people grow, and they do so in almost every dimension.

It is a few moments after noon and 11-year-old Patrik Rakovský, who has a big dream of becoming a football goalkeeper, enters into the anthropological department.
Goalkeepers need not only sharp eye and agility but also are required to have the appropriate height and arms span. An experienced physical anthropologist can estimate, based on anthropological measurements, how will the boy’s growth develop, and whether he will reach the required physical parameters.

When Patrik was born, he weighed 3350g and measured 52cm. During the first year of his life and adolescence he was growing very fast, and this process will be climaxed no sooner than by the ossification of growth cartilages of the long bones. During this developmental period his body will undergo many growth changes which result in changes of size, shape and proportions. The parts that will grow the most are the extremities, while head grows the least.

Until the second or third year of age it is the gene pool what determines most of our growth (approximately 50 to 70 percent). In the next phases of development the external environment gets to the forefront, along with the composition and quality of nourishment, quality of health care, hygienic conditions, family background and psychological well-being of the individual.

“The most fundamental anthropometric measurements which we monitor regularly are stature and height. The stature of children under 2 years of age is measured in a lying position using bodymeter – so-called “small trough” (korýtko). Adults are measured in a standing position.  Also we typically keep records of head circumference, along with stomach and waist circumference,“ says Pavel Bláha, associate professor at the department of anthropology and human genetics of the Faculty of Natural Sciences at Charles University.

A physical-anthropological research is a long-term and time consuming matter, one which requires assistance of pediatricians, biology teachers, but also of students of biological subjects initiated into the measurements, or also of students of anthropology. Preschool children undergo measurements by pediatricians in healthcare facilities, school age children are measured by their teachers of physical education and biology on the basis of written instructions. The acquired data are then processed statistically at the department of biostatistics and information technology at the National Institute of Public Health.

“The results of these physical-anthropological researches serve first and foremost as growth standards. Measurement of other children will then be compared to these standards in order for the pediatrician to determine if the growth and development of an individual is adequate to their age,“ says the associate professor Bláha. Table charts (so-called percentiles) where the growth measurements are stated in relation to the age of a child from the date of his or her birth to the age of eighteen allow pediatricians to determine the exact degree of growth deviation from the average growth measurements. If the pediatrician finds out that the development of specific growth parameters of the child deviates considerably from the standards of healthy development, he can provide against more complicated health issues from occurring later (for instance by supplying additional growth hormone). Along with the skull growth indexes and BMI (Body Mass Index) these standards are – since these are values that can monitor, in significant ways, a healthy child growth and development – a part of the appendix of the Health and Vaccination Record of a Child and Adolescent.

The first more sweeping anthropological measurements, similar to the one Tomáš underwent, was the measuring of the Czech people by the physician and anthropologist Jindřich Matiegka performed on occasion of the famous Ethnographic Czechoslovakian exhibition in Prague in 1895, which, in festive fashion, presented the rich ethnography of Czech people and initiated a deeper interest in Czech folk lore and culture.

At that time our male predecessors measured 168 centimeters, which is by 12 centimeters less than men measure today. Women then measured 156cm. In spite of the praised greatness of the Czech nation, Czech and Moravian people were, at least according to the anthropometric data provided by John Komlos, a professor of the Munich University, distinctly the shortest nation of the Habsburg monarchy. According to Komlos this was the result of excessive population density and of the industrial nature of the environment ─ food had to be imported and the lack of quality nourishment resulted in smaller stature in the population.

Present-day social conditions are in many ways different, which manifests also in our increasing growth values. Since the first large scale anthropological research in 1895 there has been an increase of average stature in twelve-year-old boys and girls by 18 centimeters. “If we compare statures of twelve-year-old to fifteen-year-old boys and girls in the year 1895 with the stature of the present-day population, we find out that children today reach the adequate values as soon as between the ages of nine to eleven years of age. We can see that in the prepubescent period there is an average increase in growth of up to three years in comparison to the year 1895,” points out associate professor Pavel Bláha.

Yet, it was not by only better socioeconomic conditions which accelerated the growth of Czech people since the beginning of the 19th century. “For instance vaccination and antibiotics totally changed the health state of entire populations of children. Infectious diseases which had been very serious in the past, often deadly or burdening in the long run (such as high occurrence of tuberculosis a century ago) ceased to be a problem. Though today there still are some serious growth diseases, these affect only a small fraction of the child population and they do not affect the growth of Czech population as a whole,” says professor Jan Lebl, who is the head physician of the clinic for children and adolescents at Královské Vinohrady University College Hospital. These and other circumstances are related to the phenomena of “secular acceleration” (from the Latin word saeculum ─ century) which is from the second half of the 20th century thought of as connected to the growth of overall stature.

Adult Czech men of today averagely measure 180cm and women average 167cm, while at the end of the nineteenth century men measured less by 10cm and women by 7.5cm on average (a difference of twelve or thirteen centimeters between the average height of men and women is present practically in all nations and ethnical groups).

Changing environment also results in gradual decrease of the age of commencement and conclusion of sexual maturity. One hundred years ago boys reached full stature in the ages of 21 to 22 years of age, while now men are fully grown in only 18 years. Girls generally reach their full stature on average two years earlier than boys do. Yet, the steady increase in stature of infantile, adolescent and adult population that is present today attests to a constantly improving socio-economic conditions of all age groups of the Czech population.

This is also related to the fact that scientific researches also prove that the trend of taller stature (caused especially by better nourishment that is rich especially in proteins) is positively connected to health, lifespan and reproduction. Professor Lebl also adds: “As was proven by recent historical researches, as late as at the end of the 19th century the daily intake (in calories or joules) in the most advanced countries in Europe (France and Great Britain) corresponds to current situation in the poorest countries in sub-Saharan Africa. The fact is that the whole generations of children were starving. From the middle of the 20th century till today in the advanced part of Europe virtually nobody starves. In fact, nowadays poor people are more likely to be obese than rich ones. It seems that we reached an optimum situation and further improving of the nourishment will not affect growth in stature significantly.”

We can see, therefore, that improvements in the standard of living of the society brings along negative effects as well. This concerns especially weight increase, which, along with growth in stature, is brought about by bigger worth of nutrition connected to the decreasing physical activity of the population (playing videogames, watching TV). On the grounds of measuring using the Body Mass Index (weight in kilograms divided by square number of height in meters) the number of obese children almost doubled in the period from 1991 till today. While there was only 3 percent of obese boys between the ages of 7 and 11, now the number is 5.6  percent in boys and 5 percent in girls. There are other problems children have as a result of accelerated growth today as well. As associate professor Bláha points out: “It is no exception when a child grows by 25 centimeters in the period of the first four years in school. Yet, he has to sit at the same desk for the whole period. Over time he has to slouch down which leads to many cases of children with problems related to bad posture. Schools do not seem to consider this at all. While the children grow over time the desks they sit at remain the same. There are two sizes of school desks ─ one for children in the primary school and the other for the secondary school. There is no regard to the actual stature of the pupils. And the result? Bad posture and spine curvature.”

Another change in growth, one you would not spot so easily as the noticeable increase in height of a Czech stature, is a change in the shape of the skull.  If we look back into our history for a moment, one of the mysteries of Czech middle age are the so far unexplained rapid changes from the long-headed Czech type, which was predominant before the 13th and 14th centuries, and which suddenly changed into the short-headed type (at this period our region was flooded with the Germanic ethnic group, which is basically long-headed).

The fact that the shape and proportions of a skull can change in relation to a change in environment or other non-genetic factors was noticed as soon as by the anthropologist Franz Boas, who in 1912 published the results of his extensive anthropometric research of almost 18 000 immigrants in the US, where, among the analyzed Italians, Hungarians, Jews and Poles, Czech and Slovak people were also present. A part of the conclusion of the extensive research was the claim that the shape of the skulls of children born in the United States differs from those of their parents.

For the Czech population round shape of head was typical for a long time. At the beginning of the twentieth century Appollinaire described the inhabitants of Prague as „round-headed folk drinking beer in their city.“  Yet it comes out that, especially from the 80’s of the twentieth century heads of the Czech people are constantly becoming more narrow and elongated while retaining the same circumference (the so-called tendency to dolichocephalization). This trend is evident in other countries as well, for instance in Poland and in Germany.

“In our country, however, it is a fairly quick process with many factors contributing to It,“ says associate professor Pavel Bláha from the Faculty of Natural Sciences at Charles University. Associate professor Hana Krásničanová, who, as a clinical auxologist, systematically studies this phenomenon, says:” One of the significant factors is positioning of the child in the first months of the child’s life. Roughly till the 80’s of the twentieth century children were usually kept reclining on their back, covered and to some extent fixated in swaddling clothes.  Adopting western trends brought about jumpers and with them the freer position lying on the stomach. This leads to the opposite pressure on the head than wha  used to be the case before, so that the skull can form the narrower and elongated shape. Under normal conditions, skull forms naturally according to the growth and shape of the human brain, which is evident for instance in children of primitive peoples who do not lay their children on the ground but carry them with them practically all day long. Current pediatric trend, or perhaps a straight imperative, recommends a return to the back positioning of the newborns.
Alongside the described phenomenon of dolichocephalization ─ narrowing and elongation of the heads while retaining the same circumference is, from the year 1961 till today, another documented phenomenon is an increase of the overall size of the brain-case in the Czech population.

Observing the proportions and growth of the brain-case and of the face as well as of the changes of selected proportion relations of the proportions of the head has irreplaceable significance in pediatrics, plastic surgery, stomatochirurgy and obstetrics. Sometimes, however, the growth measurements are exaggerated by the media. Ing. Jana Vigner says: “Somewhere in newspapers I came across the information that heads of newborn babies are becoming bigger and therefore most women will probably soon be delivering only by Caesarean operation. This is not true. There have also been rumors that the average birth weight is increasing, yet these data are not yet processed statistically.”

Till the last anthropological research (2001) there was also a long-term trend that pupils in Prague were generally the tallest, while in Prague there is also relatively the biggest number of people with higher education. “People with higher education are more aware of the needs of the children, such as adequate nourishment, sufficient sleep, adequate physical activity or mental needs of the children. They are also able to pay more and structure the activities of the children in their leisure time,“ associate professor Bláha explains.

The question suggests itself whether Czech people will, due to the increase in average height, continue to grow on and on.  “Probably not,” says associate professor Hana Krásničanová from the pediatric clinic of the 2nd Medical Faculty of Charles University. “The increase of average stature has been decreasing in the last years, and, according to computer simulations of further development of growth we can assume that we have reached a maximum of our hereditary growth potential ─ a certain balanced optimum state, and that the present growth factors will not continue to make the stature of Czech population taller, even by better nutrition or social factors.”

While in Czech population there is still some increase in stature, in the US the trend is basically the opposite. Professor  Komlos says: “The stature of the American underwent a significant change in half a century unnoticed ─ from the tallest nation in the world around second world war Americans changed into one of the most obese nations at the beginning of the 21st century. Plentiful of food is not a guarantee of its nutritious quality. Overeating and subsequent dieting do not mean eating healthily.“ American men reach an average of 175cm in height, while British men are taller by 3cm, Czechs by 5cm and Dutchmen, the tallest Europeans, by as much as 9cm of average height.

Professor John Komlos, who was trying to track certain links between height, health of a nation and economics explains the height superiority of Dutchmen in this way: “Dutchmen have the biggest population thanks to their care of unborn children and infants, which is the best in the world. On the other hand 40 million Americans do not even have health insurance. There are probably other factors at work as well ─ especially the structure of immigrants. At least till the middle of the previous century these were mostly Europeans, while in the last decades it is mostly poor South-Americans and people of Asian origin who typically have more subtle stature.”

In accord to the medical-anthropological research we can say that healthy and optimum growth of a human is a significant prerequisite and an indicator of his healthy development.  It comes out that the proverbial „small Czech man“ is more a result of a limited national self-confidence than of a small stature. The average height of Czech infantile, adolescent and adult population has increased significantly during the last century and continues to increase slightly, which can be considered a significant factor of improving socio-economic “health” of the Czech society as well as of its future healthy development and growth.

Even the anthropologist Jindřich Matiegka, the founder of the tradition of routine anthropometric measurements tried, in his end words of his writing „The physical features of the Czech people/Tělesné vlastnosti českého lidu“ in 1895, to boost Czech self-confidence and sense of exceptionality of the Czech population on the basis of the attributed physical qualities of the then „small“ Czech nation:

“As is clear from the previous text, Czech folk can pride in excellent physical characteristics as they display features such as middle and higher stature, they have bigger representation of the brown-skinned type, have bigger number of ginger-haired as well as of blue-eyed individuals, relatively short skull, voluminous brain, good development of bones and muscles etc. With their physical features the Czech people differ somewhat from the other European nations, as well as from their closest neighbors, and thus the Czech nation is a marked stone in the mosaic of the European nations, perhaps even a group of stones; we saw that Czech nation does not exhibit unified constitution. There are local deviations, in some ways very far-reaching ones. (….). We should, therefore, be aware of our strength, respect our physical advantages, protect our health and improve our natural fitness and abilities ─ and then the Czech nation will be provided the best for any future that will come.

National Geographic CR

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