Physical fitness normative values for 6–18-year-old Greek boys and girls, using the empirical distribution and the lambda, mu, and sigma statistical method

Normative-referenced values for health-related fitness among Czech youth: Physical fitness data from the study IPEN Adolescent Czech Republic

OBJECTIVES

The aim of this study was to developed sex- and age-specific normative-referenced percentile values for health-related fitness among 12 to 18 years old Czech youth.

METHODS

This study included cross-sectional data from 1,173 participants (50.7% boys) collected between 2013 and 2016. Participants were recruited from 32 elementary or secondary schools across eight cities located in the Czech Republic. Health-related fitness was objectively measured using both anthropometric (height, body mass, and sum of skinfolds) and performance (20-m shuttle run for cardiorespiratory endurance, modified push-ups for muscular strength/endurance, and V sit-and-reach for flexibility) tests. Sex- and age-specific normative values were calculated using the Lambda Mu Sigma method. Sex- and age-related differences in means were expressed as standardized effect sizes.

RESULTS

Normative percentiles were tabulated and displayed as smoothed curves. Among boys, measures of health-related fitness generally increased with age, except for an age-related decline in the sum of skinfolds and a plateau in V sit-and-reach. Among girls, most measures of health-related fitness increased from age 12 to 16 years before stabilizing, except for the sum of skinfolds, which remained stable from age 12 to 18 years. The sex-related differences were large with boys having higher cardiorespiratory endurance and muscular strength/endurance than girls. Girls compared to boys had higher flexibility.

CONCLUSIONS

This study presents the most up-to-date sex- and age-specific normative-referenced percentile values for health-related fitness among Czech youth. Normative values may be useful for fitness and public health screening and surveillance, for example, by helping to identify youth with low fitness who might benefit from a fitness-enhancing intervention.

Effects of a daily physical activity intervention on the health-related fitness status of primary school children: A cluster randomized controlled trial

An important barrier for a nationwide implementation of a daily physical activity (PA) at primary schools is the lack of spatial and human resources. Therefore, we developed a PA intervention that can be implemented without additional spatial resources or changes in school curricula. In the intervention group, children received a daily PA unit consisting of physical education lessons and simultaneous academic content over a 9-month period. The control group received conventional (physical education) classes. Body weight, height, waist circumference and health-related fitness parameters were measured. Of 412 children (9.7 ± 0.5 years) included, 228 participated in the intervention group. In regression analysis adjusted for baseline, gender, school location, sports club membership (total only) with standardized outcome variables, the intervention group showed a reduction in waist-to-height ratio (B = 0.30, p < 0.001) and an increase in several fitness parameters (cardiorespiratory endurance: B = 0.20, p = 0.037; lower body muscle strength: B = 0.11, p = 0.041; lower body muscle endurance: B = 0.12, p = 0.027; flexibility: B = 0.19, p = 0.019) compared to the control group. Intervention effects for cardiorespiratory endurance and flexibility were more pronounced in the group of children without sports club membership. Thus, especially children with no sport club membership seem to benefit from daily PA in school (Trial registration: DRKS00025515).

European fitness landscape for children and adolescents: updated reference values, fitness maps and country rankings based on nearly 8 million test results from 34 countries gathered by the FitBack network

OBJECTIVES

(1) To develop reference values for health-related fitness in European children and adolescents aged 6-18 years that are the foundation for the web-based, open-access and multilanguage fitness platform (FitBack); (2) to provide comparisons across European countries.

METHODS

This study builds on a previous large fitness reference study in European youth by (1) widening the age demographic, (2) identifying the most recent and representative country-level data and (3) including national data from existing fitness surveillance and monitoring systems. We used the Assessing Levels of PHysical Activity and fitness at population level (ALPHA) test battery as it comprises tests with the highest test-retest reliability, criterion/construct validity and health-related predictive validity: the 20 m shuttle run (cardiorespiratory fitness); handgrip strength and standing long jump (muscular strength); and body height, body mass, body mass index and waist circumference (anthropometry). Percentile values were obtained using the generalised additive models for location, scale and shape method.

RESULTS

A total of 7 966 693 test results from 34 countries (106 datasets) were used to develop sex-specific and age-specific percentile values. In addition, country-level rankings based on mean percentiles are provided for each fitness test, as well as an overall fitness ranking. Finally, an interactive fitness platform, including individual and group reporting and European fitness maps, is provided and freely available online (www.fitbackeurope.eu).

CONCLUSION

This study discusses the major implications of fitness assessment in youth from health, educational and sport perspectives, and how the FitBack reference values and interactive web-based platform contribute to it. Fitness testing can be conducted in school and/or sport settings, and the interpreted results be integrated in the healthcare systems across Europe.

Centile Reference Curves of the SLOfit Physical Fitness Tests for School-Aged Children and Adolescents

ABSTRACT

Blagus, R, Jurak, G, Starc, G, and Leskošek, B. Centile reference curves of the SLOfit physical fitness tests for school-aged children and adolescents. J Strength Cond Res 37(2): 328-336, 2023-The study provides sex- and age-specific centile norms of Slovenian children and youth. Physical fitness was assessed using the SLOfit test battery on population data, including 185,222 children, aged 6-19 years, measured in April and May 2018. Centile curves for both sexes and 12 test items were constructed using the generalized additive models for location, scale, and shape (GAMLSS). Boys generally achieved higher scores in most of the physical fitness tests, except in stand and reach, but this was not consistent throughout childhood and adolescence, nor did it pertain to the entire range of performance. Girls outperformed boys in the arm-plate tapping test throughout childhood; the poorest performing girls outperformed the poorest performing boys in the 600-m run, 60-m dash, backward obstacle course, and standing broad jump. The shapes and trends of physical fitness curves adequately reflect the effects of growth and development on boys' and girls' physical performance. Comparing the existing reference fitness curves showed that Slovenian children and adolescents display higher fitness levels than their peers from other countries. This study provides the most up-to-date sex- and age-specific reference fitness centile curves of Slovenian children, which can be used as benchmark values for health and fitness monitoring and surveillance systems.

Association between physical fitness and anthropometric, cardiovascular and socioeconomic risk factors in primary schoolchildren in KwaZulu‑Natal Province, South Africa

Background. Physical fitness (PF) status in children has been identified as a predictor of chronic disease risk factors, and has also been linked to various non-communicable diseases and an increased risk of premature death in adulthood. Studies have shown that PF has been declining. In South Africa (SA), a similar trend is noted and attributed to urbanisation and shifts from traditional active practices to sedentary lifestyles.  Objectives. To examine possible associations between PF levels and socioeconomic status (SES) and anthropometric and cardiovascular risk factors among 407 primary schoolchildren aged 6 - 13 years in KwaZulu-Natal Province, SA.  Methods. In a cross-sectional study, children’s PF scores were assessed using the Eurofit test battery: sit and reach, standing long jump (SLJ), sit-ups (SUs), 5 m shuttle run (5m-SRT) and cricket ball throw (CBT). SES was assessed using a structured questionnaire. Standardised procedures were used for anthropometric and cardiovascular measures.  Results. Girls weighed significantly more than boys (p=0.001) and had a significantly higher body mass index (BMI) (p<0.001), waist circumference (WC) (p<0.001) and hip circumference (HC) (p<0.001), while boys performed significantly better in SLJ (p=0.030), SUs (p=0.022), CBT (p<0.001) and 5m-SRT (p<0.001). A significant low negative correlation was found between PF and BMI (r=–0.151; p=0.002), WC (r=–0.107; p=0.031) and HC (r=0.123; p=0.013). Multinomial logistic regression analysis identified BMI as the main predictor of low PF (odds ratio 1.16; 95% confidence interval 1.01 - 1.33) in this cohort of primary schoolchildren. The occurrence of low PF status in children of primary school age may be influenced by gender and adiposity.  Conclusion. Assessment of PF at policy levels as part of the health screening process may help create a more explicit depiction of the health status of children and assist in early identification of risk factors. 

The Level and Factors Differentiating the Physical Fitness of Adolescents Passively and Actively Resting in South-Eastern Poland-A Pilot Study

Physical activity (PA) is defined as any bodily movement produced by skeletal muscles that requires energy expenditure. Due to civilization's development, we can observe a global decline in physical activity which negatively affects the state of physical and mental health. The physical activity of children and adolescents is a counterpart to their physical fitness. There is also more frequent spending of free time in a passive way rather than actively. The aim of the study was to determine whether there are differences in the physical fitness of young people who rest passively in relation to those who rest actively. In addition, it was checked whether factors, such as age, weight, body height and BMI differentiate the level of fitness in adolescents. Study group: 25 boys and 25 girls declaring active leisure activities. Control group: 25 boys and 25 girls declaring passive leisure activities. Age of the respondents ranged from 11 to 15 years (Me = 13; SD = 1.23). The research used: the author's questionnaire and the Index of Physical Fitness of K. Zuchora. The results were statistically developed. The youth who spend their free time actively were characterised by a higher level of physical fitness than their peers who choose passive recreation. The students with a higher BMI obtained worse results than the children with a lower body mass index. In both groups, slightly better results were obtained by girls. A significant relationship between age and results has been observed in the control group-the results increased with increasing age. The level of physical fitness is higher in active forms of recreation than in passive rest. Physical fitness tends to increase with age but decreases with increasing BMI. Girls are characterised by a higher level of physical fitness than boys.

Relationships Between Sports Club Participation and Health Determinants in Adolescents and Young Adults

Physical fitness is a powerful marker of health in adolescents and young adults. The purpose of this study was to measure the relationships between age, sex, body mass index, and sports club participation on physical fitness. The population included 49,988 participants (23,721 girls and 26,267 boys) who were divided into five age groups (11–12, 13–14, 15–16, 17–18, and 19–21 years). Body mass index was calculated. Physical fitness was assessed with the Diagnoform^® Tonic battery. Sports club participation was also documented. The practiced sport was collected. The effects of age, sex, body mass index class, and sports club participation were tested. Boys' PF increased with age at a faster rate and was better than that of girls, except for flexibility (p < 0.001). For girls, a decrease was observed in endurance, speed and flexibility at 17-18 years. Sports club participation was greater for boys at every age. Obese participants had the lowest physical fitness and sports club participation. Sports club participation increased physical fitness. Team sports seemed best for improving physical fitness, except flexibility. The study shows that sports club participation may be a key element for building health in adolescents. Preventive healthcare projects that promote sports club are needed to target sports club dropouts (obese adolescents and girls). Bridges should be built between physical education classes and sports clubs in adolescence to improve the health status of young people.

Effect of timing of school enrollment on physical fitness in third graders

Timing of initial school enrollment may vary considerably for various reasons such as early or delayed enrollment, skipped or repeated school classes. Accordingly, the age range within school grades includes older-(OTK) and younger-than-keyage (YTK) children. Hardly any information is available on the impact of timing of school enrollment on physical fitness. There is evidence from a related research topic showing large differences in academic performance between OTK and YTK children versus keyage children. Thus, the aim of this study was to compare physical fitness of OTK (N = 26,540) and YTK (N = 2586) children versus keyage children (N = 108,295) in a representative sample of German third graders. Physical fitness tests comprised cardiorespiratory endurance, coordination, speed, lower, and upper limbs muscle power. Predictions of physical fitness performance for YTK and OTK children were estimated using data from keyage children by taking age, sex, school, and assessment year into account. Data were annually recorded between 2011 and 2019. The difference between observed and predicted z-scores yielded a delta z-score that was used as a dependent variable in the linear mixed models. Findings indicate that OTK children showed poorer performance compared to keyage children, especially in coordination, and that YTK children outperformed keyage children, especially in coordination. Teachers should be aware that OTK children show poorer physical fitness performance compared to keyage children.

Percentile Curves for Multiple Physical Fitness Components Among Chinese Han Children and Adolescents Aged 7-18 Years From a National Survey Based on the Total and the Normal Weight Population

Introduction: To develop sex- and age-specific percentile curves for seven physical fitness components for Chinese Han children and adolescents aged 7–18 years based on the total and the normal weight population using a nationally representative sample.

Methods: A total of 214,228 Chinese Han children and adolescents aged 7–18 years old with all nutritional status and 161,999 with normal weight were examined. Seven physical fitness components [forced vital capacity (FVC), standing long jump (SLJ), 50-m dash, sit-and-reach (SR), grip strength (GS), body muscle strength (BMS), and endurance running (ER)] were measured, and percentile curves for each physical fitness component at the 20th, 40th, 60th, and 80th percentiles were calculated using the general additive model for location, scale, and shape (GAMLSS).

Results: Physical fitness presents different characteristics in each subgroup of sex, age, and nutritional status among children and adolescents. Sex- and age-specific percentiles for the seven physical fitness components among the Chinese Han children and adolescents aged 7–18 years based on the total and the normal weight population were provided as curves. Boys performed better than girls in FVC, SLJ, 50-m dash, GS, and ER but worse in SR. The performances of FVC, SLJ, 50-m dash, GS, BMS, and ER increased with age, but the estimates of SR were at the bottom among boys aged 12 years and girls aged 11 years. The annual increments of all components were larger in boys than girls at the peak time, which was earlier in girls than boys. The gap of physical fitness components between sexes increased with age, especially during puberty (since after 11 years old).

Conclusion: The present study described the percentile curves of seven physical fitness components among the Chinese Han children and adolescents based on the total and the normal weight population at the national level, which could help to chart the level of physical fitness across age span and identify the extreme populations with either health concerns or potential talents.

Age and sex effects in physical fitness components of 108,295 third graders including 515 primary schools and 9 cohorts

Children's physical fitness development and related moderating effects of age and sex are well documented, especially boys' and girls' divergence during puberty. The situation might be different during prepuberty. As girls mature approximately two years earlier than boys, we tested a possible convergence of performance with five tests representing four components of physical fitness in a large sample of 108,295 eight-year old third-graders. Within this single prepubertal year of life and irrespective of the test, performance increased linearly with chronological age, and boys outperformed girls to a larger extent in tests requiring muscle mass for successful performance. Tests differed in the magnitude of age effects (gains), but there was no evidence for an interaction between age and sex. Moreover, "physical fitness" of schools correlated at r = 0.48 with their age effect which might imply that "fit schools" promote larger gains; expected secular trends from 2011 to 2019 were replicated.

Students Living in the Islands are Heavier and have Lower Fitness Levels Compared to their Mainland Counterparts; Results from the National Action for Children's Health (EYZHN) Program

Few studies have examined variations in obesity by geographic location in youth and its relation with fitness levels. The present study investigated the association between geographic status (islands versus mainland), excess of body weight and fitness levels among 335.810 schoolchildren (male: 51.3%, 6-18 y, during the school year 2014-2015). Students' anthropometric parameters and fitness levels - accessed via the Euro-fit test - were measured by trained physical education teachers and evaluated according to published norms. Prevalence of overweight (23.0 Vs 21.8%) and obese (10.1 Vs 8.0%) was significantly higher for students living in the islands contrary to their mainland counterparts. A significant difference was also observed for centrally obese children (33.5 Vs 28.2%). Except for speed test .408), in all other four fitness tests, the students from the islands presented significantly lower performance (≤25^th percentile of published age- and sex-specific normative values) versus their mainland counterparts. Boys and girls living in the islands had 48% and 37% increased odds of low physical fitness (as a total), respectively, compared to their mainland counterparts. Likewise, children living in islands presented increased odds of being overweight or obese by 19% and 15% in boys and girls, respectively, as compared to those living in the mainland. Increased general and abdominal adiposity have a direct negative impact on students' performance in Physical Fitness tests. Our data highlight the problem of excessive body weight that children living in rural areas, face.

Regulation data for the horizontal jump of children and adolescents

The Horizontal Jump (HJ) is a daily tool that could be used to categorize the level of muscle fitness performance of the lower limbs. The goal was to compare the muscle fitness with those of international studies and to propose percentiles to assess the HJ performance of children and adolescents. A cross-sectional study was conducted. A total number of 3023 children and adolescents between the ages of 6.0 to 17.9 were studied. Weight, height, waist circumference (WC), and lower limb muscle fitness were evaluated. The student HJ performance values in Chile were inferior when compared to HJ performance in Brazil, Poland and Europe. For the Greek study, differences occurred only from age 6 to 15 years old. In comparison to Colombia, students showed better muscle fitness performance. These differences appeared in childhood and lasted until the beginning of adolescence. Percentiles were created to assess the lower limb fitness being an easy tool to be used and applied to classify lower limb strength.

Physical fitness reference standards for Chinese children and adolescents

To develop age- and sex-specific physical fitness reference standards and express the age- and sex-related differences using standardized effect sizes for Chinese children and adolescents. A total of 85,535 children and adolescents (48.7% girls) aged 7–18 years were recruited from six geographical divisions of China using a stratified randomized cluster sampling method. Seven physical fitness items including grip strength, standing long jump, 30-s sit-ups, sit and reach, 50-m dash, 20-s repeated straddling, and 20-m SRT were measured following a standardized procedure. Percentile curves for each physical fitness test were calculated using the LMS. Age- and sex-related differences were expressed as standardized effect sizes. We observed that the performance improved with age along with the analyzed percentiles in all tests. Boys had higher values compared to girls in all the physical fitness items except for sit and reach test, where girls showed better performance in all analyzed percentiles. Also, the sex differences increased with ages except sit and reach. There is a need for a differentiated approach in the physical education class in terms of adjustment of physical activity based on sex, level of fitness abilities in China.

Transgender Women in the Female Category of Sport: Perspectives on Testosterone Suppression and Performance Advantage

Males enjoy physical performance advantages over females within competitive sport. The sex-based segregation into male and female sporting categories does not account for transgender persons who experience incongruence between their biological sex and their experienced gender identity. Accordingly, the International Olympic Committee (IOC) determined criteria by which a transgender woman may be eligible to compete in the female category, requiring total serum testosterone levels to be suppressed below 10 nmol/L for at least 12 months prior to and during competition. Whether this regulation removes the male performance advantage has not been scrutinized. Here, we review how differences in biological characteristics between biological males and females affect sporting performance and assess whether evidence exists to support the assumption that testosterone suppression in transgender women removes the male performance advantage and thus delivers fair and safe competition. We report that the performance gap between males and females becomes significant at puberty and often amounts to 10-50% depending on sport. The performance gap is more pronounced in sporting activities relying on muscle mass and explosive strength, particularly in the upper body. Longitudinal studies examining the effects of testosterone suppression on muscle mass and strength in transgender women consistently show very modest changes, where the loss of lean body mass, muscle area and strength typically amounts to approximately 5% after 12 months of treatment. Thus, the muscular advantage enjoyed by transgender women is only minimally reduced when testosterone is suppressed. Sports organizations should consider this evidence when reassessing current policies regarding participation of transgender women in the female category of sport.

Normative health-related fitness values for French children: The Diagnoform Programme

The primary objective of this study was to establish sex- and age-specific physical fitness percentiles for French children. The secondary aim was to assess sex, weight status, and age differences for physical fitness levels in French children. A sample of 31 484 children (16 023 boys, 15 461 girls) aged 6-11 years participated in the Diagnoform programme. Cardiorespiratory fitness, muscular endurance, speed, flexibility, and agility were assessed in this national programme. Percentile values were estimated as a function of age stratified by sex using a parametric method providing smooth centile curves and explicit formulae for the centile estimates. Values from the 10th to the 90th percentile are reported. The influence of body weight according to sex on the physical fitness level was also examined using an analysis of covariance adjusted for age. Physical fitness levels were slightly better in boys, except for agility and flexibility, in which girls performed better (Cohen's coefficient, 0.20-0.45; P < .001). All physical fitness tests were significantly associated with age (P < .0001). In general, overweight and obese children had a significantly poorer physical fitness level compared with their normal-weight counterparts (P < .05). No difference was found between thin and normal-weight boys and girls, except for agility (P < .05). Reference values provide normative data for French children, and these data should be useful for identifying special needs for appropriate intervention programmes.

Physical Fitness and Anthropometric Values Among Lithuanian Primary School Children: Population-Based Cross-Sectional Study

Emeljanovas, A, Mieziene, B, Cesnaitiene, VJ, Fjortoft, I, and Kjønniksen, L. Physical fitness and anthropometric values among Lithuanian primary school children: population-based cross-sectional study. J Strength Cond Res 34(2): 414-421, 2020-The purpose of the current study was to derive representative reference scores on anthropometric measures and test scores for the musculoskeletal, motor, and cardiorespiratory fitness of Lithuanian primary school children according to age and sex. This cross-sectional design study included 3,456 Lithuanian first- to fourth-grade children from age 6 to 10 years. Physical fitness was measured using a nine-item test battery developed by Fjørtoft et al. The test battery included the following tests: standing broad jump (explosive strength), jumping a distance of 7 m on 2 feet, jumping a distance of 7 m on 1 foot (both tests indicate leg muscle strength), throwing a tennis ball with one hand, and pushing a medicine ball with 2 hands (both tests indicate arm muscle strength). These tests measured musculoskeletal fitness. In addition, there were measures of a 10 × 5-m shuttle run (agility), running 20 m as fast as possible (speed), and climbing wall bars (coordination)-general tests of motor fitness. Reduced 6-minute Cooper test (endurance) measured cardiorespiratory fitness. A Student's t test and analysis of variance were performed to indicate differences between sexes and across age, respectively. The significant differences in mean scores in anthropometric and fitness means indicated that boys had higher scores than girls, and older children scored higher than younger children (p < 0.05). Data on normative sex- and age-specific percentile values (3rd, 10th, 25th, 50th, 75th, 90th, and 97th) for physical fitness tests in Lithuanian primary school children are provided. These data are useful for educational settings, parents, clinicians, sports organizations, and sports clubs in identifying problems or outstanding performance and providing sports programs that develop children's athletic performance.

The 20-m Shuttle Run: Assessment and Interpretation of Data in Relation to Youth Aerobic Fitness and Health

Cardiorespiratory fitness (CRF) is a good summative measure of the body's ability to perform continuous, rhythmic, dynamic, large-muscle group physical activity, and exercise. In children, CRF is meaningfully associated with health, independent of physical activity levels, and it is an important determinant of sports and athletic performance. Although gas-analyzed peak oxygen uptake is the criterion physiological measure of children's CRF, it is not practical for population-based testing. Field testing offers a simple, cheap, practical alternative to gas analysis. The 20-m shuttle run test (20mSRT)-a progressive aerobic exercise test involving continuous running between 2 lines 20 m apart in time to audio signals-is probably the most widely used field test of CRF. This review aims to clarify the international utility of the 20mSRT by synthesizing the evidence describing measurement variability, validity, reliability, feasibility, and the interpretation of results, as well as to provide future directions for international surveillance. The authors show that the 20mSRT is an acceptable, feasible, and scalable measure of CRF and functional/exercise capacity, and that it has moderate criterion validity and high to very high reliability. The assessment is pragmatic, easily interpreted, and results are transferable to meaningful and understandable situations. The authors recommend that CRF, assessed by the 20mSRT, be considered as an international population health surveillance measure to provide additional insight into pediatric population health.

Making a Case for Cardiorespiratory Fitness Surveillance Among Children and Youth

We review the evidence that supports cardiorespiratory fitness (CRF) as an important indicator of current and future health among school-aged children and youth, independent of physical activity levels. We discuss the merit of CRF measurement for population health surveillance and propose the development of CRF guidelines to help support regional, national, and international surveillance efforts.

Association of Anthropometric and Lifestyle Parameters with Fitness Levels in Greek Schoolchildren: Results from the EYZHN Program

Objective

The aim of the study was to evaluate physical fitness (PF) and identify its anthropometric and lifestyle determinants in a sample of Greek schoolchildren.

Methods

The study sample consisted of 335,810 schoolchildren (♂: 51.3%, 6–18 years old). Students’ anthropometric parameters and PF levels—assessed via the Eurofit test battery—were measured by trained physical education teachers and evaluated according to the available norms, while their lifestyle habits were assessed through a questionnaire.

Results

In all applied PF tests, students’ performance was negatively associated with the presence of obesity and central obesity, defined through international criteria for body mass index and waist to height ratio, respectively. According to multiple logistic regression analysis, the presence of overweight/obesity [odds ratio (OR): 4.43, 95% confidence interval (CI): 3.98–4.93], low adherence to the MD (KIDMED ≤ 3) (OR: 1.27, 95% CI: 1.09–1.48), and increased time spent in sedentary activities (>2 h per day) (OR: 1.16, 95% CI: 1.03–1.29) were positively associated with poor PF, after adjusting for age and sex. In contrast, for every 1 day increase in the weekly frequency of engagement in athletic activity, the probability of poor PF decreased by 26% (OR: 0.74, 95% CI: 0.72–0.77). In a similar model, the presence of central obesity emerged as an even stronger possible predictor of poor PF (OR: 5.20, 95% CI: 4.66–5.78), compared to the presence of general obesity.

Conclusion

Higher general or abdominal adiposity, as well as the adoption of a low-quality diet and a sedentary lifestyle, is strongly associated with low PF levels during childhood.

European normative values for physical fitness in children and adolescents aged 9-17 years: results from 2 779 165 Eurofit performances representing 30 countries

OBJECTIVE

To develop sex-specific and age-specific normative values for the nine Eurofit tests in European children and adolescents aged 9-17 years.

METHODS

A systematic review was undertaken to identify papers that explicitly reported descriptive results for at least one of nine Eurofit tests (measuring balance, muscular strength, muscular endurance, muscular power, flexibility, speed, speed-agility and cardiorespiratory fitness (CRF)) on children and adolescents. Data were included on apparently healthy (free from known disease/injury) children and adolescents aged 9-17 years. Following harmonisation for methodological variation where appropriate, pseudodata were generated using Monte Carlo simulation, with population-weighted sex-specific and age-specific normative centiles generated using the Lambda Mu Sigma (LMS) method. Sex-specific and age-specific differences were expressed as standardised differences in means, with the percentage of children and adolescents with healthy CRF estimated at the sex-age level.

RESULTS

Norms were displayed as tabulated centiles and as smoothed centile curves for the nine Eurofit tests. The final dataset included 2 779 165 results on children and adolescents from 30 European countries, extracted from 98 studies. On average, 78% of boys (95% CI 72% to 85%) and 83% of girls (95% CI 71% to 96%) met the standards for healthy CRF, with the percentage meeting the standards decreasing with age. Boys performed substantially (standardised differences >0.2) better than girls on muscular strength, muscular power, muscular endurance, speed-agility and CRF tests, but worse on the flexibility test. Physical fitness generally improved at a faster rate in boys than in girls, especially during the teenage years.

CONCLUSION

This study provides the largest and most geographically representative sex-specific and age-specific European normative values for children and adolescents, which have utility for health and fitness screening, profiling, monitoring and surveillance.

Review of criterion-referenced standards for cardiorespiratory fitness: what percentage of 1 142 026 international children and youth are apparently healthy?

PURPOSE

To identify criterion-referenced standards for cardiorespiratory fitness (CRF); to estimate the percentage of children and youth that met each standard; and to discuss strategies to help improve the utility of criterion-referenced standards for population health research.

METHODS

A search of four databases was undertaken to identify papers that reported criterion-referenced CRF standards for children and youth generated using the receiver operating characteristic curve technique. A pseudo-dataset representing the 20-m shuttle run test performance of 1 142 026 children and youth aged 9-17 years from 50 countries was generated using Monte Carlo simulation. Pseudo-data were used to estimate the international percentage of children and youth that met published criterion-referenced standards for CRF.

RESULTS

Ten studies reported criterion-referenced standards for healthy CRF in children and youth. The mean percentage (±95% CI) of children and youth that met the standards varied substantially across age groups from 36%±13% to 95%±4% among girls, and from 51%±7% to 96%±16% among boys. There was an age gradient across all criterion-referenced standards where younger children were more likely to meet the standards compared with older children, regardless of sex. Within age groups, mean percentages were more precise (smaller CI) for younger girls and older boys.

CONCLUSION

There are several CRF criterion-referenced standards for children and youth producing widely varying results. This study encourages using the interim international criterion-referenced standards of 35 and 42 mL/kg/min for girls and boys, respectively, to identify children and youth at risk of poor health-raising a clinical red flag.

International variability in 20 m shuttle run performance in children and youth: who are the fittest from a 50-country comparison? A systematic literature review with pooling of aggregate results

OBJECTIVES

To describe and compare 20 m shuttle run test (20mSRT) performance among children and youth across 50 countries; to explore broad socioeconomic indicators that correlate with 20mSRT performance in children and youth across countries and to evaluate the utility of the 20mSRT as an international population health indicator for children and youth.

METHODS

A systematic review was undertaken to identify papers that explicitly reported descriptive 20mSRT (with 1-min stages) data on apparently healthy 9-17 year-olds. Descriptive data were standardised to running speed (km/h) at the last completed stage. Country-specific 20mSRT performance indices were calculated as population-weighted mean z-scores relative to all children of the same age and sex from all countries. Countries were categorised into developed and developing groups based on the Human Development Index, and a correlational analysis was performed to describe the association between country-specific performance indices and broad socioeconomic indicators using Spearman's rank correlation coefficient.

RESULTS

Performance indices were calculated for 50 countries using collated data on 1 142 026 children and youth aged 9-17 years. The best performing countries were from Africa and Central-Northern Europe. Countries from South America were consistently among the worst performing countries. Country-specific income inequality (Gini index) was a strong negative correlate of the performance index across all 50 countries.

CONCLUSIONS

The pattern of variability in the performance index broadly supports the theory of a physical activity transition and income inequality as the strongest structural determinant of health in children and youth. This simple and cost-effective assessment would be a powerful tool for international population health surveillance.

Physical Fitness Percentiles of German Children Aged 9-12 Years: Findings from a Longitudinal Study

Background

Generating percentile values is helpful for the identification of children with specific fitness characteristics (i.e., low or high fitness level) to set appropriate fitness goals (i.e., fitness/health promotion and/or long-term youth athlete development). Thus, the aim of this longitudinal study was to assess physical fitness development in healthy children aged 9–12 years and to compute sex- and age-specific percentile values.

Methods

Two-hundred and forty children (88 girls, 152 boys) participated in this study and were tested for their physical fitness. Physical fitness was assessed using the 50-m sprint test (i.e., speed), the 1-kg ball push test, the triple hop test (i.e., upper- and lower- extremity muscular power), the stand-and-reach test (i.e., flexibility), the star run test (i.e., agility), and the 9-min run test (i.e., endurance). Age- and sex-specific percentile values (i.e., P₁₀ to P₉₀) were generated using the Lambda, Mu, and Sigma method. Adjusted (for change in body weight, height, and baseline performance) age- and sex-differences as well as the interactions thereof were expressed by calculating effect sizes (Cohen’s d).

Results

Significant main effects of Age were detected for all physical fitness tests (d = 0.40–1.34), whereas significant main effects of Sex were found for upper-extremity muscular power (d = 0.55), flexibility (d = 0.81), agility (d = 0.44), and endurance (d = 0.32) only. Further, significant Sex by Age interactions were observed for upper-extremity muscular power (d = 0.36), flexibility (d = 0.61), and agility (d = 0.27) in favor of girls. Both, linear and curvilinear shaped curves were found for percentile values across the fitness tests. Accelerated (curvilinear) improvements were observed for upper-extremity muscular power (boys: 10–11 yrs; girls: 9–11 yrs), agility (boys: 9–10 yrs; girls: 9–11 yrs), and endurance (boys: 9–10 yrs; girls: 9–10 yrs). Tabulated percentiles for the 9-min run test indicated that running distances between 1,407–1,507 m, 1,479–1,597 m, 1,423–1,654 m, and 1,433–1,666 m in 9- to 12-year-old boys and 1,262–1,362 m, 1,329–1,434 m, 1,392–1,501 m, and 1,415–1,526 m in 9- to 12-year-old girls correspond to a “medium” fitness level (i.e., P₄₀ to P₆₀) in this population.

Conclusions

The observed differences in physical fitness development between boys and girls illustrate that age- and sex-specific maturational processes might have an impact on the fitness status of healthy children. Our statistical analyses revealed linear (e.g., lower-extremity muscular power) and curvilinear (e.g., agility) models of fitness improvement with age which is indicative of timed and capacity-specific fitness development pattern during childhood. Lastly, the provided age- and sex-specific percentile values can be used by coaches for talent identification and by teachers for rating/grading of children’s motor performance.