Grupos de la constitución del cuerpo. en mujeres kirguisas / Groups of the body constitution in kyrgyz women

Introduction. It should be considered that the body constitution which is widely used in the preventive and clinical medicine, leaves an imprint on the body mass index. The objective of this work is to study the features of body mass index and fat body mass in females of different constitutional and age groups. Materials and Methods. Using the method of complex anthropometry and bioimpedancemetry ("Medass"), we have also studied the physical status of 580 ethnic Kyrgyz women living in Osh, Kyrgyzstan and its surroundings. Statistical data processing included the calculation of arithmetic mean and error, as well as the minimum and maximum of each indicator (variation amplitude). The significance of difference was assessed by Student's t-test. Results. The body length and weight and, accordingly, the body mass index, significantly depend on the type of body constitution. The absolute fat mass is also unequal in women of different constitutional groups. The minimum and maximum of the absolute and percentage fat mass in women of the period of adulthood II with different body constitutions are, in general, more than in juvenile period. Conclusion. The obtained results can be used to develop measures aimed at the timely detection of overweight and obesity as well as for the implementation of measures to prevent alimentary-related diseases in juvenile and adulthood period. Somatometric assessment of the physical development can be used in the dynamic monitoring of health status in organized groups: in educational institutions, youth sports schools, enterprises.

Genetic and Environmental Overlaps Among Sasang Constitution Types: A Multivariate Twin Study.

According to the Sasang theory, humans can be categorized into one of the four Sasang constitution (SC) types. The four SC types are Tae-Yang (TY), Tae-Eum (TE), So-Yang (SY), and So-Eum (SE), which are determined mainly on the basis of anthropometric characteristics, personality, and the balance of the physiological functions of the major organ systems. There is a growing recognition in the complementary and alternative medicine area that SC types have the potential to be a useful scientific tool for the prevention, diagnosis, and treatment of diseases (Cooper, Evidence Based Complementary and Alternative Medicine, Vol. 6 (Suppl. 1), 2009, pp. 1-3). The main purposes of the present study are to estimate genetic and environmental influences on SC types, and to explore genetic and environmental correlations that affect phenotypic associations among the SC types. In total, 1,742 (365 monozygotic male, 173 dizygotic male, 675 monozygotic female, 271 dizygotic female, and 258 opposite-sex dizygotic) twins (mean age = 19.1 ± 3.1 year) completed a Sasang questionnaire. Univariate and multivariate model-fitting analyses were performed. Total (additive and non-additive) genetic influences were 71% for males and 81% for females in TE, 70% for males and 71% for females in SE, and 47% for both sexes in SY. Non-additive genetic effects were substantial, and shared environmental influences were negligible in most SC types. Multivariate model-fitting analysis revealed that non-additive genetic and individual-specific environmental correlations between TE and SE were -0.92 (95% CI [-0.89, -0.93]) and -0.62 (95% CI [-0.57, -0.68]), respectively. The corresponding estimates were -0.55 (95% CI [-0.48, -0.61]) and -0.44 (95% CI [-0.37, -0.51]) between TE and SY and 0.19 (95% CI [0.09, 0.29]) and -0.40 (95% CI [-0.32, -0.47]) between SE and SY. These results suggest that the phenotypic associations among SC types may be mediated by pleiotropic mechanism of genes.

The relationship between skin function, barrier properties, and body-dependent factors.

BACKGROUND: Skin is a multilayer interface between the body and the environment, responsible for many important functions, such as temperature regulation, water transport, sensation, and protection from external triggers. OBJECTIVES: This paper provides an overview of principal factors that influence human skin and describes the diversity of skin characteristics, its causes and possible consequences. It also discusses limitations in the barrier function of the skin, describing mechanisms of absorption. METHODS: There are a number of in vivo investigations focusing on the diversity of human skin characteristics with reference to barrier properties and body-dependent factors. RESULTS: Skin properties vary among individuals of different age, gender, ethnicity, and skin types. In addition, skin characteristics differ depending on the body site and can be influenced by the body-mass index and lifestyle. Although one of the main functions of the skin is to act as a barrier, absorption of some substances remains possible. CONCLUSIONS: Various factors can alter human skin properties, which can be reflected in skin function and the quality of everyday life. Skin properties and function are strongly interlinked.

[Comparative characteristics of physical development of children and adolescents of the 1st and 2nd generation of European natives of the Magadan region].

In the paper there are presented results of investigations of indices of the physical development of male adolescents aged of 11-17 years - residents of the 1-2 generation from new coming European migrants in the Magadan region during 2008-2014. There were observed 418 adolescents - representatives of the 1 generation, and 463 cases from the 2 generation. Representatives of the 2 generation in the initial period (11-12 years) were established to show higher tempos of growth. Maximal gains in the body length, body mass, and chest circumference in adolescents of the 1 generation occur at the age of 13-14 years, but in the 2 generation it is seen one year later - at the age of 14-15 years. In adolescents of each generation there was noted the high variability of the level of major indices of the physical development. However, among representatives of the 1 generation there is less proportion of cases with normal or average values of body length, body mass, and chest circumference along with larger proportion ofpersons with diverse deviations, as well deficit as excess in comparison with the 2 generation. At the final stage of the puberty age (17 years) more adolescents with microsomatic (25%) and disharmonic (38.2%) body constitution occur among the subjects from the 1 generation as compared to those of the 2 generation (19.7% and 28.2%, respectively).

[Peculirities of physical development and state of the cardiovascular system in young males from various districts of Northeast of Russia].

The comparative research was carried to study basic indices of physical development and cardiovascular system in Aboriginals and north-born Europeans of different areas of Russia's northeast (Chukotsky Autonomous District, Magadan Region). According to most examined morphofunctional characteristics no significant differences were found between the groups of subjects that testify to the formation, under the current social conditions, of convergent adaptation processes typical for the two ethnic cohorts from the observed areas of residing. High percentage of asthenia in body constitution of young residents from Magadan Region was common and mostly demonstrated by Aboriginals of the Magadan city.

Constraint, natural selection, and the evolution of human body form.

Variation in body form among human groups is structured by a blend of natural selection driven by local climatic conditions and random genetic drift. However, attempts to test ecogeographic hypotheses have not distinguished between adaptive traits (i.e., those that evolved as a result of selection) and those that evolved as a correlated response to selection on other traits (i.e., nonadaptive traits), complicating our understanding of the relationship between climate and morphological distinctions among populations. Here, we use evolutionary quantitative methods to test if traits previously identified as supporting ecogeographic hypotheses were actually adaptive by estimating the force of selection on individual traits needed to drive among-group differentiation. Our results show that not all associations between trait means and latitude were caused by selection acting directly on each individual trait. Although radial and tibial length and biiliac and femoral head breadth show signs of responses to directional selection matching ecogeographic hypotheses, the femur was subject to little or no directional selection despite having shorter values by latitude. Additionally, in contradiction to ecogeographic hypotheses, the humerus was under directional selection for longer values by latitude. Responses to directional selection in the tibia and radius induced a nonadaptive correlated response in the humerus that overwhelmed its own trait-specific response to selection. This result emphasizes that mean differences between groups are not good indicators of which traits are adaptations in the absence of information about covariation among characteristics.

Biosocial comparison of mid-upper arm circumference in the two Koreas.

Anthropometric differences between the two Koreas are of considerable public and scientific interest given the unique socio-political status of North Korea and the fact that the nations share the same genetic ancestry. This study provides new biosocial evidence on these differences by analysing mid-upper arm circumference (MUAC) as a human welfare indicator. This is the first study to compare the nutritional status of adults surveyed inside North Korea with South Koreans. The MUAC measurements of 2793 North Korean women obtained through a household survey conducted in 2002 were compared with those of 1428 South Korean women surveyed around 2003. Comparative analysis was conducted by plotting centiles and calculating mean differences in MUAC by age. This paper finds that the MUAC of the South Koreans was on average 2.8 cm greater than that of their North Korean peers, with MUAC gaps ranging from 1.6 cm to 3.9 cm and becoming more pronounced with age. This research confirms previous studies on height and weight in the two Germanies and in the two Koreas that have shown that biosocial performance is worse in socialist economies as compared with free-market regimes.

Racial difference in lean mass distribution among reproductive-aged women.

OBJECTIVE: Lean mass is an important determinant of bone mineral density (BMD) accrual, yet data regarding its correlates based on multiethnic premenopausal women are lacking. We examined the influence of age, race/ethnicity, and lifestyle variables on total and regional lean mass distribution in this population. DESIGN: A cross-sectional study was conducted on 708 healthy Black, White, and Hispanic women aged 16-33 years who were seen in an outpatient clinic. In addition, 218 of these women were followed for up to 36 months to observe changes in the relevant variables. We measured body weight, height, and lean mass distribution using a digital scale, wall-mounted stadiometer, and dual-energy absorptiometry (DXA), respectively. Multiple linear regression and mixed-model regression analyses were used to model the relationship of age, race/ethnicity and lifestyle variables to total and regional lean mass. RESULTS: For a given body mass index (BMI), Black women had higher total body lean mass (LM(total)) and leg lean mass (LM(leg)) than White and Hispanic women. Hispanic women had significantly lower LM(total), trunk lean mass (LM(trunk)), and LM(leg) than Black and White women. The difference between Blacks and Whites with regard to LM(total) significantly magnified with increasing BMI. Weight-bearing exercise and age at menarche were positively associated with lean mass variables, while parity was negatively associated with LM(leg). LM(total) and LM(trunk) increased over 36 months. Calcium intake was positively associated with increase in LM(totaI) over time. CONCLUSIONS: Our study shows that racial differences exist in the distribution of lean mass for a given BMI among reproductive-aged women.

A study of anthropometric characteristics between Malaysian and Saudi Arabian males aged 20 to 30 years.

This study presents a comparison of the anthropometric characteristics of 241 Malaysian and 646 Saudi Arabian males aged 20 to 30 years. The mean values, standard deviation (SD), and 5th and 95th percentile values of 26 measurements and 22 proportions of each group were given. The results showed that there were significant differences in a number of body dimensions between these populations, except for eye height and elbow height (standing) and height, eye height, shoulder height, and elbow height (sitting). These results are important for the ergonomic design of workstations, personal protective equipment, tools, interface systems and furniture: The presented data may be useful for providing a safer, more productive and user-friendly workplace for Malaysian and Saudi Arabian populations.

Mammographic density in a multiethnic cohort.

OBJECTIVES: To compare mammographic density among premenopausal and early perimenopausal women from four racial/ethnic groups and to examine density and acculturation among Japanese and Chinese women. DESIGN: The study included 391 white, 60 African American, 171 Japanese, and 179 Chinese participants in the Study of Women's Health Across the Nation, a multisite study of US women transitioning through menopause. Mammograms done when women were premenopausal or early perimenopausal were assessed for area of dense breast tissue and the percent of the breast occupied by dense tissue (percent density). Information on race/ethnicity, acculturation, and other factors was obtained from standardized instruments. Multiple linear regression modeling was used to examine the association between race/ethnicity or acculturation and density measures. RESULTS: Age-adjusted mean percent density was highest for Chinese (52%) and lowest for African American (34%) women. After additional adjustment for body mass index, menopause status, age at first birth, breast-feeding duration, waist circumference, and smoking, African Americans had the highest mean percent density (51%) and Japanese women had the lowest (39%). In contrast, the area of dense tissue was highest for African Americans and similar for white, Japanese, and Chinese women. Less acculturated Chinese and Japanese women tended to have a larger area of density and a higher percent density. CONCLUSIONS: Neither the age-adjusted nor fully adjusted results for percent density or area of dense tissue reflected current differences in breast cancer incidence rates among similarly aged African American, Japanese, Chinese, and white women. In addition, mammographic density was higher in less acculturated Asian women.

Patrones antropométricos de los recién nacidos a término de grupos étnicos de raza no caucásica procedentes de África subsahariana, Marruecos y Sudamérica nacidos en Cataluña / Anthropometric patterns in non-Caucasian full-term neonates of African, Moroccan and South American origin born in Catalonia (Spain)

Introducción El incremento de la inmigración en las últimas décadas en España ha determinado un aumento del número de recién nacidos de raza no caucásica en nuestro medio. El objetivo fue establecer los valores de normalidad de desarrollo intrauterino del peso, la longitud y el perímetro craneal de una población de recién nacidos a término (RNAT) de raza no caucásica. Pacientes y métodos Se han incluido un total de 2.444 recién nacidos de 37-42 semanas de gestación (1.230 varones, 1.214 mujeres), producto de gestaciones únicas, sin malformaciones congénitas y de curso normal de los siguientes grupos étnicos de raza no caucásica y procedentes de África subsahariana (raza negra) (n 5 1.257; 622 niños, 635 niñas), de origen marroquí (n 5 520; 297 niños, 223 niñas) y de Sudamérica (n 5 667; 356 niños, 311 niñas). Se han calculado los valores de la media y las desviaciones típicas para cada semana de gestación de cada sexo y raza. Los resultados obtenidos se han comparado con relación a los de la población autóctona. Resultados Los valores antropométricos de los RNAT de raza negra son similares a los valores de la población catalana. Sin embargo estos valores son superiores en los recién nacidos de origen marroquí y sudamericanos con respecto a la población de referencia. Las diferencias son estadísticamente significativas en todos los parámetros evaluados a partir de las 38 semanas de gestación en la población de origen marroquí con relación a la población catalana. En la población sudamericana se han observado diferencias estadísticamente significativas a partir de la 38 semana de gestación en las niñas y a partir de la 40 semana de gestación en los niños. La existencia de dimorfismo sexual en los parámetros antropométricos evaluados no es constante en todas las edades gestacionales consideradas. Conclusiones Los patrones antropométricos de la población de RNAT de raza caucásica y nacionalidad española no son extrapolables a la hora de evaluar un RNAT de otro grupo étnico

Introduction The rise in immigration to Spain in recent decades has increased the number of non-Caucasian newborns in our environment. The aims of this study were to establish normal intrauterine development values for weight, length and head circumference in a population of non-Caucasian full-term newborns (FTN). Patients and methods We studied 2,444 healthy full-term singleton newborns (37-42 weeks' gestational age; 1,230 boys, 1,214 girls) with the following ethnic origins: black (n 5 1,257; 622 boys, 635 girls), Moroccan (n 5 520; 297 boys, 223 girls) and South-American (n 5 667; 356 boys, 311 girls). Mean values and standard deviations were estimated for each week of gestation for sex and race and these values were compared with those of a Spanish population of the same gestational age and sex. Results Anthropometric values in black FTN were similar to those of the Catalan population. By contrast, these values were higher in Moroccans and South-American FTN than in the native population. Statistically-significant differences were observed in all the parameters evaluated from the 38th week of gestation in full-term Moroccan newborns compared with the reference population. Statistically significant differences were observed in full-term South-American newborns from the 38th week of gestation in girls and from the 40th week in boys. The presence of sexual dimorphism in the anthropometric patterns evaluated was not constant at all the gestational ages evaluated. Conclusions Anthropometric patterns of the Spanish Caucasian FTN population are not extrapolable to FTN of other ethnicities

Japanese men have larger areas of visceral adipose tissue than Caucasian men in the same levels of waist circumference in a population-based study.

Visceral adipose tissue (VAT) is an independent risk factor for metabolic and cardiovascular disorders. There has been no study that demonstrated different abdominal fat distribution between Asian and Caucasian men. As the Japanese are less obese but more susceptible to metabolic disorders than Caucasians, they may have larger VAT than Caucasians at similar levels of obesity. We compared the abdominal fat distribution of the Japanese (n=239) and Caucasian-American (n=177) men aged 40-49 years in groups stratified by waist circumference in a population-based sample. We obtained computed tomography images and determined areas of VAT and subcutaneous adipose tissue (SAT). We calculated VAT to SAT ratio (VSR). The Japanese men had a larger VAT and VSR in each stratum, despite substantially less obesity overall. In multiethnic studies, difference in abdominal fat distribution should be considered in exploring factors related to obesity.

Clinical and genetic associations with hypertriglyceridemic waist in a Canadian aboriginal population.

OBJECTIVES: To determine the prevalence of 'hypertriglyceridemic waist' (HTGW) in Oji-Cree, to examine its interaction with hepatic nuclear factor-1alpha (HNF1A) in association with type 2 diabetes, and to characterize its putative genetic determinants. METHOD: The presence or absence of HTGW was determined in 522 Oji-Cree subjects (223 males, 299 females), >or=18 years of age, in whom physical measurements and fasting plasma analyte concentrations were gathered, and a 75-g oral glucose tolerance test was administered, as part of a cross-sectional study. Subjects were genotyped for HNF1A codon 319, angiotensinogen (AGT) codons 174 and 235, G-protein beta3-subunit (GNB3) nucleotide 825, fatty acid-binding protein (FABP2) codon 54, nucleotides -455 and -482 of the apolipoprotein (apo) C-III (APOC3) promoter, and a 5-bp insertion/deletion polymorphism within the 3'-untranslated region of protein phosphatase 1 regulatory subunit 3 (PPP1R3). RESULTS: The unadjusted prevalence of HTGW in Oji-Cree adults was 20.5%, with more males affected than females (27.8 vs 15.1%, P=0.0004). Logistic regression analysis, adjusted for age and gender, showed type 2 diabetes was associated with both HNF1A G319S (odds ratio (OR) 4.85, 95% CI 2.45, 9.58) and HTGW (OR 4.96, 95% CI 2.49, 9.88). When the HNF1A mutation and HTGW were present in combination, the OR for type 2 diabetes was markedly increased (OR 43.2, 95% CI 12.4, 150). In women only, both GNB3 825C>T and FABP2 A54T genotypes were significantly associated with HTGW (OR 2.02, 95% CI 1.01, 4.05 and OR 1.95, 95% CI 1.01, 3.74, respectively). CONCLUSIONS: HTGW is prevalent in Oji-Cree, especially in men. The ORs for type 2 diabetes were similar ( approximately 5-fold) for subjects with either the presence of HTGW or the private HNF1A G319S mutation. These two independent risk factors acted synergistically to confer an even greater increased risk of type 2 diabetes.

Abdominal fat distribution and functional limitations and disability in a biracial cohort: the Atherosclerosis Risk in Communities Study.

OBJECTIVE: To examine the associations of abdominal fat and obesity with functional limitations and disability in late adulthood. DESIGN: Longitudinal, cohort study. PARTICIPANTS: African American and white men and women aged 45-64 y at baseline with measured waist circumference, waist-to-hip ratio (WHR), and body mass index (BMI) who participated in the Atherosclerosis Risk in Communities (ARIC) Study (n = 9416). OUTCOME MEASURES: Self-reported functional limitations, activities of daily living (ADLs), and instrumental activities of daily living (IADLs) at ages 52-75 y. RESULTS: Waist circumference, WHR, and BMI were positively associated with functional limitations and ADL and IADL impairment approximately 9 y later among African American and white men and women. For example, in African American women the odds ratios (95% CI) associated with a one standard deviation (s.d.) increment in waist circumference (13.3 cm) for severe functional limitations and ADL and IADL impairment were 2.36 (2.00-2.79), 1.41 (1.25-1.58), and 1.49 (1.34-1.66), respectively. In white women, the odds ratios (95% CI) were 2.66 (2.39-2.96), 1.60 (1.47-1.74), and 1.42 (1.31-1.53), respectively. Similar associations were found in men. A 1 s.d. increment in WHR (0.08 U) and BMI (5.06 kg/m2) produced similar results. The associations of waist circumference and WHR with functional limitations and ADL and IADL impairment were attenuated but, in general, remained statistically significant when BMI was added to the models. CONCLUSIONS: Maintaining a healthy body weight and avoiding increases in abdominal fat should be investigated for their potential to reduce the risk of functional limitations and disability in an aging population.

Associations between food variety and body fatness in Hong Kong Chinese adults.

BACKGROUND: Food variety is reported to be closely associated with body fatness in Caucasians. The association has not been examined in a Chinese population. OBJECTIVE: To examine the association between food variety and body fatness in Hong Kong Chinese adults. DESIGN: One hundred and twenty Hong Kong Chinese adults (aged 18-50 y). Usual dietary intake over a one-week period of all subjects was assessed by using a food frequency questionnaire. Anthropometric parameters were measured using standardized methods. RESULTS: Varieties of grain and meat were negatively correlated with obesity indices (grain vs. BMI/body fat/waist/hip circumferences: partial r = -47/-0.43/-0.46/-0.42, p < 0.001; meat vs. BMI/body fat/waist/hip circumferences: partial r = -0.31/-0.24/-0.25/-0.29, p < 0.01). In contrast, there was a positive relationship between variety of snack and obesity indices (snack vs. BMI/body fat/waist/hip circumferences: partial r = 0.35/0.42/0.42/0.36, p < 0.001). A food variety ratio derived from varieties of snack, grain and meat, was a stronger predictor of body fat compared with dietary fat in a regression model. CONCLUSION: Food variety may contribute to the local escalation in the prevalence of obesity. The variety of snack is the promoting factor for obesity while the variety of grains and meats may counteract its development. The findings of this study may have implications for treatment of obesity and the prevention of further weight gain.

Health and sociodemographic factors associated with body weight and weight objectives for women: 2000 behavioral risk factor surveillance system.

BACKGROUND: The increasing body mass index (BMI) of women in the United States gives rise to concerns about associated comorbid conditions and decreases in life expectancy. Also of concern are underweight women, especially as the result of an eating disorder or undernutrition. METHODS: Data from a national sample of women aged > or =18 years (n = 98,387) are used to examine the relationship between health and sociodemographic factors (diabetes, physical activity, self-rated health, smoking status, weight loss attempts, age, and education) and body weight (BMI, desired weight). Models are stratified by race. RESULTS: Roughly 70% of the women in each race/ethnic group (72.0% white women, 68.3% black women, 69.4% Hispanic women) wanted to weigh less, and just under one half of the women were actively trying to lose weight. A notable percentage of women who were classified as obese indicated that they were at their ideal weight and desired no weight change. Most women had not received advice from a health professional in the past year regarding their weight, and most were not engaging in the optimally recommended level of physical activity. CONCLUSIONS: Results document the range of satisfaction with current weight among adult women and capture low levels of health practitioner involvement in issues of weight. Perception of weight, combined with BMI, will need to be assessed to determine how best to proceed toward an ideal weight and satisfaction with that weight.

The association between global self-esteem, physical self-concept and actual vs ideal body size rating in Chinese primary school children.

OBJECTIVE: To investigate whether the discrepancy between actual and ideal body size rating is related to Chinese children's global self-esteem and global physical self-concept. DESIGN: A cross-sectional study of school children who completed questionnaires related to global self-esteem, global physical self-concept, and actual vs ideal body size. SUBJECTS: A total of 386 Chinese children (44% girls and 56% boys) aged 7-13 y from a primary school in Hong Kong, China. MEASUREMENTS: Global self-esteem and physical self-concept were measured using the physical self-descriptive questionnaire. Actual vs ideal body size discrepancy was established using the silhouette matching task. RESULTS: No significant relationship was found between global self-esteem and actual-ideal body size discrepancy of children. Global physical self-concept had a moderate negative correlation (r=-0.12) with the body size discrepancy score and the discrepancy score explained very limited variance (R(2)=0.015; F(1, 296)=4.51; P<0.05) in global physical self-concept. Three body size discrepancy groups (none, positive, and negative) were examined to see if there were any significant differences in global self-esteem, global physical self-concept, and specific dimensions of physical self-concept. A significant overall difference was found between groups for global physical self-concept (F=3.73, P<0.05) and the physical self-concept subscales of physical activity (F=3.25, P<0.05), body fat (F=61.26, P<0.001), and strength (F=5.26, P<0.01). Boys scored significantly higher than girls on global physical self-concept-especially in the sport competence, strength, and endurance subscales. CONCLUSION: This study revealed that the actual-ideal body size discrepancy rating of Chinese children was not predictive of global physical self-concept and global self-esteem. These findings are contrary to those reported in Western children, which may mean that culture plays a role in the formation of body attitude.

Differences in morphology and force/velocity relationship between Senegalese and Italian sprinters.

In order to investigate whether the supremacy of African sprinters is related to the leg extensor force/velocity relationship or to leg morphology, two groups of elite sprinters originating respectively from Senegal (S) and Italy (I) were compared in this respect. The groups included 13 S and 15 I male sprinters. Their mean best performances over 100 m during the preceding track and field season were 10.66 (0.3) and 10.61 (0.3) s (NS), respectively. Age, height and mass were similar in the two groups. The force/velocity relationship of the leg extensors was assessed during maximal half-squats on a guided horizontal barbell with masses of 20-140 kg added on the shoulders. Leg morphology was assessed by relating the sub-ischial length to the standing height (L/H) and by measuring the inertia in the vertical (IZ in kg.cm2), antero-posterior (IY, kg.cm2) and medio-lateral (IX, kg.m2) planes. The two groups developed non-different force and power when lifting the heaviest loads. Inversely, the lighter the load, the lower the force and power developed by S, as compared to I (P<0.001). S demonstrated greater L/H (P<0.001), and 26% lower IZ (P<0.01), 15% lower IY (P=0.09), and 14% lower IX (P=0.10). These results suggest that S and I sprinters were similar as regards the muscle abilities involved in slow maximal contractions. However, S demonstrated lower values in muscle abilities related to high-speed contractions, suggesting that S sprinters had a lower percentage of fast twitch fibres. This is likely to be compensated for by the lower level of internal work due to longer and lighter legs.