What significance do the results of the study “morphological evolution in Cuban sporting population, 1970-2014” have?

From the pyramidal system of Cuban sports development

According to Pancorbo (2002)Pancorbo, A.E. (2002). Medicina del Deporte y Ciencias Aplicadas al Alto Rendimiento y salud. Caxias do Sul, EDUCS., for a long time the Cuban pyramid model was composed of the following strata: 1) massive school sports areas where around 300,000 children participated, 2) special school sports areas where the level of participation only included 26.6 % of the initial total, 3) Provincial Schools for Sports Initiation where only 5.3% of the total reached, 4) Schools for Athletic Improvement where only 1.6% reached, and National Centers for adult and youth teams where only they made up 0.6% of the total that started in massive sports areas.

The pyramidal model of Cuban high performance sports complies with the Darwinian postulates of the theory of natural selection in its social application, since the elements of the Darwinian system present in its pyramidal system are: a highly variable population, represented by all, without distinction of social classes, racial groups and religious tendencies with the possibility of competing for a place; an environment where resources are scarce and there is no availability for all in a massive way as one advances in the pyramid of high performance (enrollment, skills, medicines, food, specialized medical attention, clothing); selective pressures that result in the adaptation of those who survive (being consistent with the statutes of the social system they represent and resisting multi-million dollar offers); transmission of successful characteristics to future members of this population, where not only physical characteristics are spread, but also a value system within which the training system, diet, patriotic values, biocultural inheritance, among other factors were inherited ( Old, 2009Olds, T. (2009). Body Composition and Sports performance. In: Olympic textbook of science in sport. Volume xv of the encyclopedia of sports medicine an JOC medical commission publication. p.131-140. John Wiley & Sons, Ltd., Publication. Garsington Road.).

Since the end of the eighties, the Cuban pyramid model has been constantly shaking, as the continuous migrations of athletes, scarce resources for training, talent theft, offers of multimillion-dollar income, are among the factors that have made to break a structure that today has lost intermediate links such as the Pre-EIDE (previous step of the Schools for Initiation into Scholastic Sport) and the High Schools of Athletic Perfection. On the other hand, the massive participation during the national championships has been limited, and the number of enrollments in the youth and senior national teams has been reduced, which has resulted in the escape of a morphological variability that favored that at the top the best phenotypically gifted will arrive through the sports reserves.

This phenomenon, in turn, has favored the change of perception that parents and their own talents have towards the practice of sports, many try to seek their future by practicing sports in which Cuba is considered a world power, thus guaranteeing, greater competition number, income and a decent retirement income as an internationally awarded athlete. An example of this phenomenon, at a biological level, is justified by the fact that the average height of Cuban basketball players has not changed significantly since the 1970s (Rubio,2007Rubio, F. (2007) Valoración de indicadores antropométricos en el baloncesto femenino elite y sus tendencias en el periodo: 1980-2000. [Tesis para optar por el grado de Máster en Control Médico]. Instituto de Medicina del Deporte.), although it has changed internationally (Sedeaud et al.,2014Sedeaud, A., Marc, A., Schipman, J., Schaal, K., Danial, M., Guillaume, M. et al. (2014). Secular trend: morphology and performance, Journal of Sports Science, 32, 1146-1154. https://doi.org/10.1080/02640414.2014.889841. ). On the other hand, the average volleyball player has increased his stature significantly, despite the significant emigration of the best players from Cuba since the beginning of the 21st century (Carvajal and Serviat, 2014Carvajal, W. y Serviat, N. (2014). Evolución del somatotipo de jugadores cubanos de voleibol en el período 1970-2012. Archivos de Medicina del Deporte, 1(6), 384-390. ).

Under these conditions, the original elements of the Darwinian system, present in the social field of Cuban sport, have undergone some modifications today. The new elements are: A highly variable population, represented by an increasing number of competitors, without distinction of social classes, racial groups and religious tendencies, with the possibility of competing for places in a smaller number of prioritized sports than in past decades (loss of interest in the practice of some sports and increasing increase in the practice of others); an environment where resources are more scarce and there is less availability for all as one advances in the high performance pyramid (disappearance of intermediate links of the pyramid and concentration of quality, expressed in reduction of enrollment in sports schools, an increasingly strict biological medical control); increased selective pressure (increased motivation due to salary stimulation, multi-million dollar offers, globalization); transmission of the successful characteristics to the future members of this population, where not only the new physical characteristics that disadvantage a few sports are spread, but also a value system within which more modern training systems will be inherited, feeding mode, among other factors.

A clear example of this problem is constituted by baseball player: Cuba is losing its talented athletes surprisingly and without warning. Since 1991, more than 300 Cuban baseball players defected from Cuba and in just the past 3.5 years, 5 of those players “signed contracts worth a combined $287 million” (Zaworska, 2017Zaworska N. (2017). Striking out the Cuban trade embargo: a contractual approach to the transfer of Cuban baseball players to the big leagues. Sports Lawyers Journal, 24(135), 136-163. ). Under the influence of baseball player’s defection, Cuban talents with great physical potential continue appearing. The morphological evolution has occurred favoring players of greater absolute size, responding to the increasingly growing professionalization of the sports.

Based on the trends described at the international level

At the beginning of the 20th century, Norton and colleagues made the following statement: “the evolution of body types in the athlete has often been ignored, and it was instrumental in setting most of the current records” (Norton et al., 2000, p.225Norton, K.I., T.S. Olds, S. Olive y N.P Craig (2000). Anthropometry and sports performance. In K. Norton and T.S. Olds (Eds.) Anthropometrica. P. 287-364. University of New South Wales Press ).

When these authors joined by a line the data related to the physical characteristics of the elite athletes who competed between 1925 and 2000, each sport and / or modality evidenced a different pattern of change. According to these authors, in the first decades of the 20th century, most sports showed physical characteristics close to each other, but from that moment on, the physical characteristics that favored scouts and coaches caused a radical change that dispersed the physical in all directions, looking like the pattern shown for galaxies according to the expansion model of the universe (Epstein,2014Epstein, D. (2014). The Sports Gene: Inside the Science of the Extraordinary Athletic Performance. Penguin Group. ).

For a significant group of authors, the “expanding universe” of sporting bodies showed that athletes of short absolute height remained the same size or were smaller and smaller, while athletes of greater absolute height showed increasing height (Norton and Olds, 2001Norton, K., Olds, T. (2001). Morphological evolution of athletes over the 20th century: causes and consequences. Sport Medicine, 31(11). https://doi.org/10.2165/00007256-200131110-00001 ; Norton et al.,2000Norton, K.I., T.S. Olds, S. Olive y N.P Craig (2000). Anthropometry and sports performance. In K. Norton and T.S. Olds (Eds.) Anthropometrica. P. 287-364. University of New South Wales Press ; Olds,2009Olds, T. (2009). Body Composition and Sports performance. In: Olympic textbook of science in sport. Volume xv of the encyclopedia of sports medicine an JOC medical commission publication. p.131-140. John Wiley & Sons, Ltd., Publication. Garsington Road.; Sedeaud et al.,2014Sedeaud, A., Marc, A., Schipman, J., Schaal, K., Danial, M., Guillaume, M. et al. (2014). Secular trend: morphology and performance, Journal of Sports Science, 32, 1146-1154. https://doi.org/10.1080/02640414.2014.889841. ).

According to Olds (2009)Olds, T. (2009). Body Composition and Sports performance. In: Olympic textbook of science in sport. Volume xv of the encyclopedia of sports medicine an JOC medical commission publication. p.131-140. John Wiley & Sons, Ltd., Publication. Garsington Road. this has occurred as a consequence of the increasingly marked morphological specialization, where the athletes of the same sport increasingly resemble each other in their characteristics, while they differ substantially from the athletes of other sports, a kind of “big bang” of sporting physiques.

The “expanding universe” of sporting bodies has its support in the philosophical ideas of Jean-Baptiste de Lamarck (1744-1829), this naturalist was the one who exposed that circumstances create the need, that need creates habits, habits produce modifications as a result of the use or disuse of a certain organ and the means of nature are in charge of fixing these modifications (Birx,2009Birx, J. (2009). Encyclopedia of time Science, Philosophy, Theology, & Culture. SAGE Publications).

According to Norton and Olds (2001)Norton, K., Olds, T. (2001). Morphological evolution of athletes over the 20th century: causes and consequences. Sport Medicine, 31(11). https://doi.org/10.2165/00007256-200131110-00001 the fundamental postulate of the evolutionary ideas of Charles Robert Darwin (1809-1882) “only the most capable survive” represent a fundamental challenge for morphological evolution in the athlete, this being one of the reasons why athletes act in accordance with the Olympic slogan "faster, higher, stronger".

The first compilation was made by Tanner et al. (1964), who evaluated a group of athletes participating in the Rome Olympic Games, showing that the sprinters were about 4cm taller and 7kg heavier, and 400m runners differed by about 8cm and 10kg, middle-distance 4cm and 4kg, long-distance 4cm and 1kg, and marathon 4cm and 0kg in height and weight to those studied in the 1920s (Kohlrausch et al., 1930Kohlrausch, W. (1930). Zusammenhänge von Körperform und Leistung. Ergebnisse der anthropometrischen Messungen an den Athleten der Amsterdam er Olympia de Arbeitsphysiologie.). The comparison of jumpers was just as interesting; in 1960 jumpers were 8-10cm taller and 10kg heavier, while throwers were 8-10cm taller and 25kg heavier.

Most of the publications on the subject assumed weight and body mass index as a measure of body composition in athletes, while height was assumed as an indirect measure of the evolution of body segments, considering that weight and height are the most representative variables of morphology and explain the increase in strength, speed, power and better biomechanics during performance (Norton et al., 2000Norton, K.I., T.S. Olds, S. Olive y N.P Craig (2000). Anthropometry and sports performance. In K. Norton and T.S. Olds (Eds.) Anthropometrica. P. 287-364. University of New South Wales Press ; Norton y Olds, 2001Norton, K., Olds, T. (2001). Morphological evolution of athletes over the 20th century: causes and consequences. Sport Medicine, 31(11). https://doi.org/10.2165/00007256-200131110-00001 ; Sands et al.,1012Sands, W.A., Slater, C., McNeal, J.R., Murray, S.R. & Stone, M.H. (2012). Historical trends in the size of US Olympic female artistic gymnasts. International Journal of Sports Physiology Performance, 7(4), 350-356. https://doi.org/10.1123/ijspp.7.4.350 ; Charles y Bejan, 2014Charles, J.D, Bejan, A. (2014). The evolution of speed, size and shape in modern athletics. Journal of Experimental Biology , 212(15), 2419-2425.. https://doi.org/10.1242/jed.031161 ; Sedeaud et al.,2014Sedeaud, A., Marc, A., Schipman, J., Schaal, K., Danial, M., Guillaume, M. et al. (2014). Secular trend: morphology and performance, Journal of Sports Science, 32, 1146-1154. https://doi.org/10.1080/02640414.2014.889841. )

The group of authors who have reported adaptive changes between generations for somatotype, body fat, muscle mass, among other aspects of the physical structure, such as the diameter of the pelvis and shoulders, is more limited (Olds, 2001Olds, T. (2001). The evolution of physique in male rugby union players in the twentieth century. Journal of Sports Science, 19, 253-262. https://doi.org/1080/026404101750158312 ; Cǔk et al.,2007Cǔk, I., Korencić, T., Tomazo-Ravnik, T., Pecek, M, Bucar, M., Hraski, M. (2007). Differences in morphologic characteristics between top-level gymnasts of year 1933 and 2000.Collegium Antropologicum, 31(2), 613-9.; Carvajal et al.,2008Carvajal, W., Ríos, A., Echavarría, I., Martínez, M. & Catillo, M.E. (2008). Aceleración secular en Deportistas cubanos de alto rendimiento: Periodo 1976-2008. Revista Española de Antropología Física, 28, 69-77. ; Lozovina et al.,2012Lozovina, V., Lozovina, M., Pavičić, L. (2012). Morphological changes in elite male water polo players. Acta Kinesiologica, 6(2), 85‐90.; Carvajal and Serviat, 2014Carvajal, W. y Serviat, N. (2014). Evolución del somatotipo de jugadores cubanos de voleibol en el período 1970-2012. Archivos de Medicina del Deporte, 1(6), 384-390. ; Burdukiewicz et al.,2019; Han et al.,2020; Carvajal et al., 2021Carvajal, W., León, S., González, M.E. & Deturnel, Y. (2021). Evolución morfológica de boxeadores superpesados cubanos, 1976-2014. Archivos de Medicina del Deporte, 38(5), 163-169. ).

Olds (2001)Olds, T. (2001). The evolution of physique in male rugby union players in the twentieth century. Journal of Sports Science, 19, 253-262. https://doi.org/1080/026404101750158312 reported a considerable decrease for the endomorphy, mesomorphy and ectomorphy of rugby players that significantly affected the change of the somatotype to make it considerably more mesomorphic and less endomorphic and ectomorphic, these being in correspondence with the evolution of the game.

Carvajal et al. (2008)Carvajal, W., Ríos, A., Echavarría, I., Martínez, M. & Catillo, M.E. (2008). Aceleración secular en Deportistas cubanos de alto rendimiento: Periodo 1976-2008. Revista Española de Antropología Física, 28, 69-77. found marked differences for the somatotype and body composition of Cuban athletes, related to weight-height trends at the international level. The changes were substantial in competitive art sports and in the active body substance index of a significant number of sports.

Given the limited amount of existing research at the international level, which involves the quantification of the components of body composition and somatotype (Olds, 2001Olds, T. (2001). The evolution of physique in male rugby union players in the twentieth century. Journal of Sports Science, 19, 253-262. https://doi.org/1080/026404101750158312 ; Cǔk et al.,2007Cǔk, I., Korencić, T., Tomazo-Ravnik, T., Pecek, M, Bucar, M., Hraski, M. (2007). Differences in morphologic characteristics between top-level gymnasts of year 1933 and 2000.Collegium Antropologicum, 31(2), 613-9.; Carvajal et al.,2008Carvajal, W., Ríos, A., Echavarría, I., Martínez, M. & Catillo, M.E. (2008). Aceleración secular en Deportistas cubanos de alto rendimiento: Periodo 1976-2008. Revista Española de Antropología Física, 28, 69-77. ; Lozovina et al.,2012Lozovina, V., Lozovina, M., Pavičić, L. (2012). Morphological changes in elite male water polo players. Acta Kinesiologica, 6(2), 85‐90.; Carvajal and Serviat, 2014Carvajal, W. y Serviat, N. (2014). Evolución del somatotipo de jugadores cubanos de voleibol en el período 1970-2012. Archivos de Medicina del Deporte, 1(6), 384-390. ; Queiroga et al., 2019; Carvajal et al., 2021Carvajal, W., León, S., González, M.E. & Deturnel, Y. (2021). Evolución morfológica de boxeadores superpesados cubanos, 1976-2014. Archivos de Medicina del Deporte, 38(5), 163-169. ), and taking into account that these are national in nature and involve different methodologies, there is insufficient evidence to establish to what extent the compartments associated with body composition or the components of the anthropometric somatotype have been modified at the international level.

In the world, as of 2000, 90.2% of the research articles on this topic were published; but 60.8% were published in the period from 2011 to 2020 (Figure 1). The specialized literature has approached the morphological evolution of international athletes from the anthropological-epidemiological paradigms (Norton and Olds, 2001Norton, K., Olds, T. (2001). Morphological evolution of athletes over the 20th century: causes and consequences. Sport Medicine, 31(11). https://doi.org/10.2165/00007256-200131110-00001 ; Borms, 2003Borms J. (2003). Secular changes in sport. Kinesiology. 35(1), 91-96.; Danuvio, 2008Danuvio, M.E., Sanna, E. (2008). Secular changes in human biological variables in Western Countries: an updated review and synthesis. Journal of Anthropological Sciences, 86, 91-112.), since its impact on performance (Norton et al., 2000Norton, K.I., T.S. Olds, S. Olive y N.P Craig (2000). Anthropometry and sports performance. In K. Norton and T.S. Olds (Eds.) Anthropometrica. P. 287-364. University of New South Wales Press ; Olds, 2001Olds, T. (2001). The evolution of physique in male rugby union players in the twentieth century. Journal of Sports Science, 19, 253-262. https://doi.org/1080/026404101750158312 ; Olds, 2009Olds, T. (2009). Body Composition and Sports performance. In: Olympic textbook of science in sport. Volume xv of the encyclopedia of sports medicine an JOC medical commission publication. p.131-140. John Wiley & Sons, Ltd., Publication. Garsington Road.; Sedeaud et al., 2014Sedeaud, A., Marc, A., Schipman, J., Schaal, K., Danial, M., Guillaume, M. et al. (2014). Secular trend: morphology and performance, Journal of Sports Science, 32, 1146-1154. https://doi.org/10.1080/02640414.2014.889841. ), but the fact of knowing how this phenomenon has had impact on the practice of the biomedical control of the preparation of a particular medical-sports system has not deserved serious consideration.

PARADIGM SHIFT IN KINANTHROPOMETRIC CONTROL OF PREPARATION OF THE CUBAN ATHLETES

According to Norton and Olds: “a number of social factors both drive and are driven by the search for athletes of increasingly rare morphology. These include globalization and international recruitment, greater financial and social incentives, and the use of special training methods and artificial growth stimuli” (Norton and Olds, 2001, p.763Norton, K., Olds, T. (2001). Morphological evolution of athletes over the 20th century: causes and consequences. Sport Medicine, 31(11). https://doi.org/10.2165/00007256-200131110-00001 ).

In Cuba, for the initial stage of the project "Medical Control of Training in Laboratory and Field Conditions", after the period 1991-1998, notable events had occurred:

In the specialized literature it is described that in periods of socioeconomic transformations disadvantageous changes occur at a morphological and / or physiological level (Saint-Onge et al., 2008Saint Onge, J.M., Krueger, P.M., Rogers, R.G. (2008). Historical trends in height, weight, and body mass: Data from U.S. Major League Baseball players, 1869-1983. Economics and Human Biology, 6, 482-488. https://doi.org/10.1016/j.ehb.2008.06.008 ; Berthelot et al., 2010Berthelot, G., M. Tafflet, El Helou N, Len, E., Escolano, S., Guillaume, M., et al. (2010). Athlete atypicity on the edge of human achievement: performances stagnate after the last peak, in 1988. PLoS ONE, 5(1). https://doi.org/10.1371/journal.pone.0008800 ). However, the increasingly intensive selection processes reduce the variation associated with these large social differences.

Checking any of the assumptions attributable to the impact of morphological evolution, supported by natural selection in the social field of sport in Cuba, and / or influenced by the international trends previously described, would cause a change in the practice of Kinanthropometry in Cuba. A first approach to the subject was supported by a study published in the Revista Española de Antropología Biológica during 2008. In this pilot study, Carvajal et al (2008)Carvajal, W., Ríos, A., Echavarría, I., Martínez, M. & Catillo, M.E. (2008). Aceleración secular en Deportistas cubanos de alto rendimiento: Periodo 1976-2008. Revista Española de Antropología Física, 28, 69-77. found marked differences for the somatotype and body composition of Cuban athletes, related to the tendencies of weight-stature within the Cuban sporting population, being the first existing research on the subject to date in Cuba. The changes were substantial in artistic and rhythmic gymnasts, volleyball and baseball players, while weight, height and active body substance index were the indicators that changed the most in a significant group of sports.

This first study led to a broader investigation where the evolution of body composition and somatotype of Cuban athletes in the last 45 years was analyzed. It was found that the body composition of 4096 athletes, grouped into 24 disciplines, fundamentally changed at the expense of fat-free mass, as a result of the increase in weight and height with relatively constant adiposity in many sports disciplines. The changes mentioned reinforced the appearance of an increasingly linear anthropometric profile with more discrete endomorphy levels and an emphasis on musculoskeletal development; This typology became more accentuated in the female sex where there was a significant change in the somatotype frequencies (Carvajal, 2018Carvajal, W. (2018). Evolución morfológica en la población deportiva cubana en el período 1970-2010. Implicaciones para su evaluación cineantropométrica. [Tesis para optar por el grado de Doctor en Ciencias de la Cultura Física] Universidad de las Ciencias de la Cultura Física.).

Many of the results found in the course of this long investigation will be presented below:

In general, the body weight of baseball players (pitchers, out fielders), throwing modalities (javelin, shot put, hammer), tennis, fencing, water polo, basketball and boating increased at a rate of 1.5kg / decade in males; while rhythmic gymnastics and the super heavy category of wrestling decreased this substantially (Carvajal, 2018Carvajal, W. (2018). Evolución morfológica en la población deportiva cubana en el período 1970-2010. Implicaciones para su evaluación cineantropométrica. [Tesis para optar por el grado de Doctor en Ciencias de la Cultura Física] Universidad de las Ciencias de la Cultura Física.); and in male athletes, swimming, javelin, shot and hammer athletes, super heavy wrestlers, baseball pitchers, water polo, and tennis players increased their stature at a rate greater than 1.2cm / decade since 1970 until 2010. On the other hand, the athletes of shot put, discus and javelin, long jump, volleyball, fencing and basketball players had an increase in stature of more than 1.3 cm / decade in the same period (Carvajal, 2018Carvajal, W. (2018). Evolución morfológica en la población deportiva cubana en el período 1970-2010. Implicaciones para su evaluación cineantropométrica. [Tesis para optar por el grado de Doctor en Ciencias de la Cultura Física] Universidad de las Ciencias de la Cultura Física.).

The results of research carried out in the last 20 years led to the introduction of new reference values, accompanied by more discriminating methodologies of changes in body composition due to the effect of training (Carvajal et al.,2018aCarvajal, W., León, S., González, M.E., Deturnel, Y., Echavarría, I.M. (2018). Anthropometrical characteristics of Cuban sporting population: Reference data from high performance national teams, 1992-2014. Apuntes de Medicina del Deporte, 53(200), 129-137. https://doi.org/10.1016/j.apunts.2018.07.001 ); new consensus documents and guidelines for the evaluation of the current athlete were also introduced (Carvajal et al.,2018bCarvajal, W., León, S.A., Deturnel, Y. & González, M.E. (2018). Nuevo referente de la estructura física del deportista: la composición corporal y el somatotipo de los atletas élites cubanos. Centro Nacional de Derecho de Autor. ). In the same way, the theoretical foundations of the findings were exposed in a series of literary works and scientific articles (Carvajal, 2021Carvajal, W. (2021). Bases teórico-metodológicas de la antropología biológica aplicada al deporte: el paradigma cubano. En: A. Rangel, Vázquez (Ed.), Antropología Biológica Aplicada en Cuba (pp.157-176). Editorial Universitaria “Félix Varela”.).

Practical significance of research

The practical significance of the research proposed by the authors was that established by Carter (1982)Carter, J.E.L.(Ed.). (1982) Physical Structure of Olympic Athletes Part 1: The Montreal Olympic Games Anthropological Project. Medicine and Sports, Vol 16(4). https://www.ncbi.nlm.nih.gov/pmc/about/disclaimer/ , once the dissemination of the results of the Anthropological project of the Montreal 1976 Olympic Games was concluded, in the decade after its development, common for all large-scale anthropometric studies of athletes. Its scope is in the following aspects: