Robert Malina

University of Texas at Austin | UT · Department of Kinesiology and Health Education

Background Lifestyles of contemporary children are largely organised with relatively little time for free play. Aim To compare the growth, maturity status, motor proficiency and physical fitness of non-participants and participants in organised sports 7–10 years. Subjects and methods Height, weight, skeletal age (SA), physical activity, fundament...

Addressing abdominal obesity requires multifaceted strategies, with physical activity and diet playing a pivotal role. The objective of this study was to assess alterations in body composition, adipokine concentrations, insulin resistance parameters, and lipid metabolism in males with abdominal obesity following two distinct interventions: exercise...

Objectives: The aim of this research was to evaluate changes in body composition, adipokine levels, and dyslipidemia parameters in males with abdominal obesity following two distinct interventions: exercise alone and exercise combined with an ad libitum diet. Methods: This study included 44 males with abdominal obesity (mean age 34.7 ± 5.5 years...

Purpose To track body size and proportions, arm dimensions and grip strength in children, adolescents, and adults resident in an indigenous community in Oaxaca who were measured on two or three occasions across surveys in 1968, 1978, and 2000. Methods The three cross‐sectional surveys included measures of height, weight, sitting height, arm circum...

Background Studies addressing age at peak height velocity (PHV) in longitudinal samples of participants in sports are relatively limited. Purpose To compare the growth status and estimated ages at PHV of longitudinal samples girls and boys active in sport with peers not active in sport, and to compare estimated ages at PHV among longitudinal sampl...

Age at peak height velocity (APHV) is an indicator of maturity timing which is applicable to both sexes, and which is influenced by environmental factors. The objective of this study was to assess variation in APHV associated with several indicators of socioeconomic status (SES) in a longitudinal sample of Polish adolescents. The sample included 73...

Secular change in the heights of adult men and women resident in ten rural communities in west-central Poland in four decennial surveys between 1986 and 2016 is considered. The adults were J o u r n a l P r e-p r o o f 2 parents of children attending schools in rural communities in the province of Poznań. During each survey, parents of school child...

Background Three indicators of early childhood undernutrition and associated factors are evaluated among under-5 children in five National Family Health Surveys in India spanning 1992 to 2021. Methods Data for 533,495 children under 5 years of age (U–5) were analysed in the context of three commonly used indicators of early childhood undernutritio...

Objective To estimate the associations between height, weight, and three estimates of skeletal age (SA) and the strength and motor performance of male soccer players in two chronological age (CA) groups, 9–12 ( n = 60) and 13–16 ( n = 52) years. Methods Height, weight, strength (grip), speed (5 m, 20 m sprints), acceleration (time at crossing 10 m...

The contributions of height, weight and skeletal age (SA) to strength and motor performances of male soccer players 9–12 (n = 60) and 13–16 (n = 52) years were estimated. SA was assessed with the Fels method, and was expressed as the standardized residual of the regression of SA on chronological age CA (SAsr). Static strength (right + left grip), s...

Hindus and Muslims represent the two largest religions in India, and also differ in nutritional status, health-related habits and standard of living associated with economic disparities. In this context, the present study considered estimated secular changes in body size, proportions, and weight status among Hindu and Muslim Indian men. The data ar...

Purpose To evaluate the concordance of predicted maturity status classifications (pre-, circa- or post-peak height velocity) relative to observed age at PHV in youth soccer players. Methods Longitudinal height records for 124 male soccer players were extracted from academy records spanning the 2000-2022 seasons. Age at PHV for each player was esti...

Background Motor performances of youth are related to growth and maturity status, among other factors. Aim To estimate the contribution of skeletal maturity status per se to the motor performances of female athletes aged 10–15 years and the mediation effects of growth status on the relationships. Subjects and methods Skeletal age (TW3 RUS SA), bo...

Regional variation in the body size of Indian men 18–84 years of age (birth years1891–1957) was considered. Heights, weights, and BMIs of Indian males from four regions of the country – North, East-Northeast, Central, and West were compared. Heights of men 35+ years of age were adjusted for estimated height loss with age; the estimate was added to...

Study of the morphology of adult and youth athletes has a long tradition in the sport sciences. Studies of youth ordinarily focus on body size, body proportions, and body composition in the context of growth and maturation. Heights and weights of youth athletes vary within and among sports, but differences among sports are more apparent during adol...

Bio-banding refers to grouping youth athletes within a given chronological age range into specific maturity groups based on predicted maturity status. Percentage of predicted adult height at the time of observation is the commonly used indicator of maturity status. Bio-banding is to some extent a modification of the concept of maturity-matching. Mo...

This book presents an integrated, research-driven, collection of 54 evidence-based chapters. Chapters are founded on the research and practical experience of 104 internationally renowned scientists and clinicians, from 25 countries. Each extensively referenced chapter concludes with a bulleted summary and where appropriate is cross-referenced to co...

Estimated ages at take-off (TO) and at peak height velocity (PHV) based on two models and maturity status based upon age at PHV and skeletal age (SA) were compared in a longitudinal sample of male soccer players. In addition, estimated ages at PHV in 13 longitudinal samples of soccer players were compared. The longitudinal height records of 58 play...

Objectives: To evaluate secular change in body size and weight status of adult Indian males born in 1891-1957 and surveyed in the 1970s. Methods: Data are from Anthropological Surveys. Only men were included in the surveys due to high female illiteracy and lack of female researchers. Indian society was also strongly conservative at the time, esp...

Fetal life and infancy are extremely sensitive to adverse environmental conditions. This study aimed to assess the effect of exposure to a natural disaster (cyclone Aila) in utero or during infancy on fine and gross motor functions in preadolescent Indian children. The study was conducted in West Bengal, India, and included approximately 700 childr...

Background Skeletal age (SA) is an estimate of biological maturity status that is commonly used in sport-related medical examinations. This study considered intra-observer reproducibility and inter-observer agreement of SA assessments among male tennis players. Methods SA was assessed with the Fels method in 97 male tennis players with chronologic...

External workloads associated Hockey 5 s, the new version of youth field hockey, were evaluated in 31 elite U16 male field players (15.4 ± 0.7 years) from three national teams. Mixed-longitudinal observations for the 31 players provided complete data for 33 forwards and 43 defenders. Activities of the players during games were monitored with the GP...

Environmental pollutions, particularly toxic elements such as lead, are among the most significant factors affecting the growth and functional development of children. The aim of this study was to evaluate the effect of blood lead levels on handgrip strength (HGS) in urban children resident in the Copper Basin of Lower Silesia, Poland, controlling...

External workloads associated with a new version of youth field hockey, Hockey5s, were evaluated in a sample of 31 elite male field players (15.4 ± 0.7 years; 174.2 ± 8.24 cm; 63.5 ± 8.03 kg). Players were members of U16 National Youth Field Hockey Teams. The total sample included 76 players with 33 forwards and 43 defenders. Activities of the play...

Objective: To address the relationship between socioeconomic factors and age of menarche among Polish women born and reared in periods that varied considerably in environmental stresses: the Great Depression of the 1930s, the interval of World War II, and the interval of communist rule following World War II through the 1950s. Methods: The data...

The purpose of this study was to determine intra- and inter-observer agreement for the three skeletal ages derived from the TW2 method among male pubertal soccer players. The sample included 142 participants aged 11.0–15.3 years. Films of the left hand-wrist were evaluated twice by each of two observers. Twenty bones were rated and three scoring sy...

Lead negatively affects human growth and development. In this research, we aimed to assess the effect of elevated blood lead level on age at menarche (AM), controlling for body mass index (BMI) and estimated fatness. The sample included 490 girls aged 7–16 examined in Polkowice town (Copper Basin, Poland) in 2008. Measurements included height, weig...

Aim: evaluate physical activity (PA), physical fitness (PF) and motor competence (MC) relative weight status among Cabo Verde youth. Height and weight were measured in 343 boys and girls 12-14 years. PF tests included grip strength, push-ups, curl-ups, sit-and-reach, one-mile-run/walk. KTK tests were the indicator of MC. PA was estimated with pedom...

Background: One of the components affecting the level of health is physical fitness and diets, which is also considered the foundation of a healthy lifestyle. Methods: Samples by survey ranged from 871 to 1,417 (boys) and from 843 to 1,326 (girls). Speed (5 m run), agility (figure-8-run), explosive power (vertical jump), flexibility (stand and reac...

Este libro recoge las ponencias del VI Seminario Internacional de Táctica y Técnica Deportiva organizadas por la Cátedra de Deporte y Educación Física - Centro de Estudios Olímpicos de la Universidad de Girona (antiguas Jornadas de la CEEF-CEO) dedicadas a las nuevas tendencias en el desarrollo del talento deportivo. En este libro el lector encont...

Background Concerns for youth sports in the United States often focus on early sport specialization, overemphasis on competition, injuries, and burnout. Little research has addressed relationships among the preceding and other concerns, including time away from organized sport, sleep, and perceptions of physical and psychological well-being. Hypot...

A variety of models are available for the estimation of parameters of the human growth curve. Several have been widely and successfully used with longitudinal data that are reasonably complete. On the other hand, the modeling of data for a limited number of observation points is problematic and requires the interpolation of the interval between poi...

The objective of this study was to evaluate secular changes in the Body Mass Index (BMI) and weight status of rural children and adolescents in west-central Poland across decennial surveys spanning 1986 and 2016. Participants were 8,677 boys and girls 7-15 years attending schools in 10 rural communities in 1986, 1996, 2006, and 2016. Heights and we...

The purpose of the study was to evaluate predicted maturity offset (time before age at PHV) and age at PHV (chronological age [CA] minus maturity offset) in a longitudinal sample of 58 under-13 club level soccer players in central Portugal for whom ages at PHV were estimated with the SITAR model. Two maturity offset prediction equations were applie...

Twenty-three scientists met at Krobielowice, Poland to discuss the role of growth, nutrition and economy on body size. Contrasting prevailing concepts, re-analyses of studies in Indonesian and Guatemalan school children with high prevalence of stunting failed to provide evidence for an association between nutritional status and body height. Direct...

Background: The objective of the study was to evaluate secular changes in the physical fitness of rural school youth, 7-15 years, in west-central Poland between 1986 and 2016. Methods: The fitness of cross-sectional samples of school youth resident in the same 10 communities was evaluated in 4 decennial surveys: 1986-1417 boys/1326 girls; 1996-9...

Objective The purpose of the study was to evaluate the agreement between the Fels and Greulich‐Pyle methods for the assessment of skeletal age (SA) in female youth soccer players. Methods The sample included 441 Portuguese players 10.08–16.73 years of age who regularly participated in organized and competitive soccer. Standardized radiographs of t...

Studies of age at menarche in Poland have a long history and consistently show an urban-rural gradient. The objectives of the study were to to estimate the age at menarche among school girls resident in ten rural communities of the Greater Poland province in 2016 and to compare ages at menarche by weight status and by population growth. The sample...

A maturity-associated gradient among adolescent athletes in many sports tends to favour early maturing participants. This study was aimed to describe inter-individual variance in growth and skeletal maturation among male youth table tennis. The sample included 99 players registered in competitive clubs for at least 2 years. Chronological age (CA) r...

ABSTRACT The purpose was to evaluate the implications of a proficiency barrier (PB) for physical activity (PA), sedentary time (ST) and weight status (WS) in a two-stage study. In Stage 1, motor quotient (MQ) cutoff values, based on the KTK test, for differentiating overweight/obese from normal weight, and sedentary from non-sedentary were identifi...

Reported mean ages, heights and weights of female soccer players aged <19 years in 161 studies spanning the years 1992–2020 were extracted from the literature or calculated from data available to the authors; 35 studies spanning the years 1981–2020 also included an indicator of biological maturation. Heights and weights were plotted relative to U.S...

Baseline characteristics of 31 healthy male U15 soccer players who were classified as select or non-select at the end of the season were compared. Players were 14.4 ± 0.54 years (13.6–15.3 years) at baseline; characteristics included body size, proportions and composition, estimated maturity status, several functional capacities, and coach classifi...

Background Predicted maturity offset, defined as time before peak height velocity (PHV) is increasingly used as an indicator of maturity status in studies of physical activity, fitness, and sport. Objective To validate maturity offset prediction equations in longitudinal samples of boys and girls. Methods The original and modified maturity offset...

Background: Equations predicting age at peak height velocity (APHV) are often used to assess somatic maturity and to adjust training load accordingly. However, information on the intra-individual accuracy of APHV in youth athletes is not available. Aim: The purpose of this study is to assess the accuracy of predication equations for the estimation...

Background: Equations predicting age at peak height velocity (APHV) are often used to assess somatic maturity and to adjust training load accordingly. However, information on the intra-individual accuracy of APHV in youth athletes is not available. Aim: The purpose of this study is to assess the accuracy of predication equations for the estimati...

Anthropometric, functional and physical activity characteristics of contemporary adult descendants of Upper Silesian immigrants to Texas in the mid-19th century and current residents in Upper Silesia were compared. The sample included 45 residents in Central Texas, 25 women and 20 men, and 36 residents in rural Upper Silesia, 24 women and 12 men, 5...

Objective To evaluate secular changes in the heights and weights of rural school youth in west‐central Poland across decennial surveys of the same communities spanning 1986 and 2016. Methods Heights and weights of school youth 7 to 15 years in 10 rural communities in the vicinity of the city of Poznań were measured in 1986 (1417 boys, 1326 girls),...

Background: Three commonly used non-invasive protocols are implemented to estimate the timing at which PHV most likely occurs. Accurate estimation of circumpubertal years can aid in managing training load of adolescent athletes. Aim: Three protocols were compared against observed age at PHV: an estimate of 13.8 ± 1.0 years - generic age at PHV (fr...

Background: The influence of maturity-status on athletic performance is reasonably well documented. Methodological and practical issues of assessment and lack of longitudinal data have impacted the success of various models. Aim: To develop age- and sex-specific developmental curves for sprint acceleration in elite youth tennis players and to addre...

The purpose of this study was to evaluate changes in the estimated body composition of elite female and male Polish handball players during a five-week preseason training camp. Height and weight were measured, while body composition was estimated with bioelectrical impedance in 18 male and 17 female handball players before and after the five-week t...

Background: The aim of the study was to examine the contribution of chronological age (CA), skeletal maturation, training experience and concurrent body size descriptors, to inter-individual variance in left ventricular mass (LVM) among female adolescent soccer players. Methods: The sample included 228 female soccer players 11.8-17.1 years. Trai...

Under marginal nutritional conditions, growth in utero is related to subsequent growth and adult height. The aim of this research is to compare the young adult body size of women grouped by estimated duration of pregnancy relative to World War II. Subjects were 620 university students 18-25 years, for whom archival data for date of birth, age, heig...

Objective. To test the hypothesis that assortative mating for physical characteristics differs before and after major secular increases in height in an indigenous community in the Valley of Oaxaca, Mexico. Methods. Spouse pairs were identified in household and anthropometric surveys of a Zapotec-speaking community in 1978 (n = 68-70 pairs) and 2000...

Despite significant positive developments within topics of biological anthropology, archaeology, and related academic areas in Latin America, we noted a lack of coordination and communication among them. Available publications provide syntheses within different areas of biological anthropology, yet few have attempted integration of the distinct sub...

Objective The impact, positive or negative, of youth sport specialisation (YSS) on short-term and long-term performance is not fully understood; however, the desire to maximise performance goals is generally considered the primary reason children and adolescents specialise at a young age. We performed a systematic review of original research to est...

Inter-individual differences in size, maturity status, function, and behavior among youth of the same chronological age (CA) have long been a concern in grouping for sport. Bio-banding is a recent attempt to accommodate maturity-associated variation among youth in sport. The historical basis of the concept of maturity-matching and its relevance to...

Background: The prevalence of overweight (OWT) and obesity (OB), defined by the body mass index (BMI, kg/m²) among children and youth has increased worldwide in the last 30–40 years. Aim: To evaluate the weight status, defined by the BMI, of indigenous school children and youth resident in different regions of Mexico Subjects and methods: Students...

This study examined the simultaneous effects of relative age and biological maturity status upon player selection in an English professional soccer academy. A total of 202 players from the U9 to U16 age groups, over an eight-year period (total of 566 observations), had their relative age (birth quarter) and biological maturity (categorised as late,...

Background: Individual differences in biological maturation impact player selection and development in youth football. Aim: To evaluate players perceptions of competing in a football tournament where they were matched by maturity rather than chronological age. Subjects: Participants included male junior footballers from three professional academies...

The influence of long-term disasters, wars and famines on the biological status of human populations is well documented. The purpose of this study was to assess the impact of the conditions of WW II in Poland on the height, body mass, and BMI of young adult female university students who were born before, during and shortly after the war. Subjects...

The objective of the study was to examine the effects of the relative age effect (RAE) and predicted maturity status on body size and repeated sprint ability (RSA: 7 x 34.2 m / 25 s interval) in youth soccer. The sample was composed of 197 male players aged 13-14 years. Body mass, stature, and sitting height were measured, RSA was assessed in the f...

Background: To evaluate the concordance of skeletal age (SA) with two predicted estimates of biological maturity status in elite British youth tennis players. Method: Participants were 71 male and female elite youth tennis players aged 8 to 16 years. Weight, height, and sitting height were measured. SA (Fels method) was the criterion indicator o...

Konarski, JM, Konarska, A, Strzelczyk, R, Skrzypczak, M, and Malina, RM. Internal and external loads during Hockey 5's competitions among U16 players. J Strength Cond Res XX(X): 000-000, 2019-The purpose of the study was to characterize the external and internal loads associated with Hockey 5's, the modified small-sided format of competition for U1...

Objective Evaluate the relationship between body mass index and physical fitness in a cross‐sectional sample of Brazilian youth. Methods Participants were 3849 adolescents (2027 girls) aged 10–17 years. Weight and height were measured; body mass index was calculated. Physical fitness was evaluated with a multistage 20 m shuttle run (cardiovascular...

Adolescent characteristics of young adult soccer players (n = 35) were compared with those of youth teammates (n = 124) no longer involved in soccer. Former U-13 players active in soccer as young adults were slightly later in maturation and performed better in several functional and soccer skills than youth teammates. Former U-15 players active in...

The purpose of the study was to model the longitudinal development of knee extension (KE) and flexion (KF) strength in adolescent soccer players. A mixed-longitudinal sample composed of 67 soccer players aged 11.0–13.9 years at baseline was followed on three-to-five occasions over 5 years. Stature, body mass and several skinfold thicknesses were me...

Interrelationships among skeletal maturity status, body size, ventilator thresholds (VT) and peak oxygen uptake (VO2peak) were considered in 47 adolescent male soccer players aged 12.5–15.4 years. Body mass, stature, and the triceps and subscapular skinfolds were measured. The latter were used to estimate fat mass and fat-free mass. Skeletal age wa...

Background: Comparisons of physical fitness in normal weight and overweight/obese youth generally highlight the negative consequences of an elevated BMI. In contrast, several studies of children and adolescents highlight the importance of variation in indicators of physical fitness across the full spectrum of BMIs from low through high. Aim: The pu...

Objective To analyze variation in the growth status of indigenous children and youth attending bilingual schools, escuelas albergues, for the indigenous population in México. Materials and methods The children and youth attended escuelas albergues in 1,009 localities in 21 Mexican states in 2012. Heights and weights of 31,448 boys and 27,306 girls...

Purpose: To compare characteristics of club level male soccer players 11 and 13 years of age, and to evaluate playing status in soccer two and 10 years after baseline by birth quarter (BQ). Methods: Youth players 11 (n = 62, born 1992, observed December 2003) and 13 (n = 50, born 1990, observed April 2004) years were grouped by BQ. Baseline data in...