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Secular Trends in the Performance of Children and Adolescents (1980–2000)
Abstract and Figures
It is widely believed that the performance of children and adolescents on aerobic fitness tests is declining. To test this hypothesis, this meta-analysis compared the results of 55 reports of the performance of children and adolescents aged 6–19 years who have used the 20m shuttle run test (20mSRT). All data were collected in the period 1981–2000.
Following corrections for methodological variation, the results of all studies were expressed using the common metric of running speed (km/h) at the last completed stage. Raw data were combined with pseudodata generated from reported means and standard deviations using Monte Carlo simulation. Where data were available on children and adolescents from the same country of the same age and sex, but tested at different times, linear regression was used to calculate rates of change. This was possible for 11 (mainly developed) countries, representing a total of 129 882 children and adolescents in 151 age × sex × country slices.
There has been a significant decline in performance in the 11 countries where data were available, and in most age × sex groups, with a sample-weighted mean decline of 0.43% of mean values per year. The decline was most marked in older age groups and the rate of decline was similar for boys and girls.
There has been a very rapid secular decline in the 20mSRT performance of children and adolescents over the last 20 years, at least in developed countries. The rate of decline is not related to the change in the country’s relative wealth, as quantified by per capita gross domestic product (GDP).
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... Primary trial outcome: children's CRF Children's CRF will be assessed using the validated 20 m multistage fitness test (shuttle run test). [34][35][36] This is an accepted pragmatic field-based measure of CRF, for use in public health, 37 with demonstrated validity 38 39 and reliablity. 40 41 Further, shuttle run scores are associated with a range of indicators of cardiometabolic health. ...
IntroductionMulticomponent school-based physical activity (PA) interventions can improve students' cardiorespiratory fitness (CRF) and PA. Due to the complex nature of such interventions when delivered at scale their effect sizes markedly reduce. Modifying student school uniforms, so that they are more PA enabling, may be a simple intervention that could enhance student health. The primary aim of this trial is to assess the effectiveness of an activity enabling uniform intervention (shorts, polo shirt and sports shoes) in improving children's CRF.
Methods and analysis:
A cluster randomised controlled trial will be conducted in 24 primary schools in New South Wales (NSW), Australia. Schools will be randomly allocated to either intervention or usual practice following baseline data collection. Active WeAR Everyday intervention schools will allow students in grades 4-6 (aged approx. 9-12 years) to wear their existing sports uniform (shorts, polo shirt and sports shoes) every day. To avoid any financial cost to students they will be provided with two additional sports shirts and one pair of shorts. Study outcomes will be assessed at baseline and 9 months postbaseline. The primary outcome is students' CRF measured using the 20 m multistage fitness test. Secondary outcomes include students': mean daily steps and steps/minute measured via accelerometer, quality of life, mental well-being and perceived PA self-efficacy. The acceptability, feasibility and cost of the intervention will be assessed. Analyses will be performed using an intention-to-treat framework. Linear mixed effects regression models will be used to assess intervention effects on the primary outcome at follow-up. Planned exploratory analyses will examine effects by subgroups (eg, gender).
Ethics and dissemination:
This study has received approval from Hunter New England Local Health District Human Ethics Committee (2020/ETHO2602) the University of Newcastle, Human Research Ethics Committee (H-2021-0013), NSW Department of Education (SERAP: 2020387) and Catholic School Offices.
Trial registration number:
ACTRN12621000201875.
... It was also calculated that children's fitness has declined by 0.4 percent every year over the last two decades (or 2.4 percent over a 6-year period). 12 According to this study, physically active youngsters had a substantially higher level of cardio respiratory fitness than inactive children. The similar conclusion was reached after observing a group of Spanish children. ...
... A recent systematic review analyzed the evolution of motor skills in children aged 6-18 years from 1972 to 2015, highlighted a progressive decline in aerobic fitness and muscle power between 1986 and 2010-2012, and a moderate development of muscle strength and speed in the same period [18]. Other studies associated the increasing BMI (Body Mass Index) to decline in physical fitness related to 20 m shuttle run test [19], standing long jump test, sit-and-reach test, 50 m sprint and aerobic fitness [20]. Low physical activity and higher levels of BMI were also associated with reduced motor performance more significant in boys than girls [21][22][23] and especially in the 13-14 years group [24]. ...
In the last decades, low levels of physical activity and sedentary lifestyles were associated with the progressive decline in physical fitness in children and adolescents. The present cross-sectional study aims to assess the evolution of muscular strength in adolescents in an Apulia province (Italy), comparing motor performance in 1990 and 2020. The sample consists of 107 adolescents attending secondary school in Lecce in 1990, and 118 attending the same school in 2020 (11-12 years old). After dividing the sample according to gender and BMI, muscular strength was assessed with Standing Long Jump (SLJ) and Medicine Ball Throw 2 kg (MBT). Statistical analysis included ANOVA to highlight significant differences in motor performances in 1990 and 2020 according to gender and BMI, and linear regression to investigate the variance explained by BMI on SLJ and MBT. The results showed (a) lower motor performance in 2020 compared to 1990, (b) the increase in the percentage of overweight-obese from 1990 to 2020, and (c) a negative association between BMI and the SLJ in 2020. Findings suggest the need to assess and monitor physical fitness-as a health status indicator-in adolescents, and promote further opportunities to encourage and expand the time spent in physical activity in Apulia.
Aim. The main aim of the research was to evaluate and compare changes in accuracy of throws performed by KS Cracovia 1906 handball players, before and after endurance effort. Basic procedures. The study was carried out among14 players who played in the second women’s handball division in the 2016/2017 season. The study took place during final preparations for the season, at the beginning of September 2016. The level of durability of the tested players was assessed using the Beep Test and the accuracy of throws, both before and after the endurance effort (after the Beep Test), was analysed, considering the training and endurance experience of the tested handball players. Basic methods of descriptive statistics, the Student’s t-test and Spearman’s rank correlation coefficient were used in the preparation of the results, and to assess the size of differences between the individual players, normalised indicators were calculated. Results main findings. Analysis of the research results presented in the study showed that after a long-term effort of endurance nature, the accuracy of throws among the tested handball players decreased. It seems that they suffered from nervous system fatigue leading to less accurate and less precise performance of motor tasks. Conclusions. On the basis of the analysis performed in the study, the following conclusions were drawn: that the accuracy of throws among KS Cracovia 1906 handball players after a long endurance effort, significantly decreased, and the accuracy of throws, both before and after the endurance effort, does not depend on the training period. Furthermore, more time should be devoted to the formation of aerobic strength in training the tested team.
O presente ensaio tem como objetivo discutir as coincidências, convergências e divergências entre a abordagem desenvolvimentista da Educação Física escolar (AD) e os programas de atividade física visando à saúde (PAFVS) no que se refere a trato com as habilidades motoras fundamentais (HMF). A coincidência está no fato de o desenvolvimento de HMF constituir-se um foco importante de intervenção em ambos. Na AD está atrelado a objetivos educacionais de formação do cidadão; no PAFVS aos objetivos de saúde do indivíduo, particularmente à prevenção de doenças crônico-degenerativas. A convergência está em enfatizar a relevância das HMF para o desenvolvimento ulterior e contínuo de habilidades motoras específicas. Sem uma base motora bem desenvolvida na infância relativamente a HMF, o envolvimento com a prática sistemática de habilidades motoras específicas na adolescência e na idade adulta fica prejudicado. Como consequência, a promoção e a manutenção de saúde ficam dificultadas. A divergência está no fato de o desenvolvimento de HMF se constituir, na AD, um objetivo a ser alcançado, enquanto que no PAFVS ele é um meio para a saúde. Para a AD, a aquisição de habilidades motoras, sejam elas fundamentais ou específicas, não se configura um meio para alcance de outros objetivos, por exemplo, a saúde. Isto não quer dizer que ela esteja dissociada dos objetivos de saúde, visto que, como consequência do processo de aquisição de habilidades motoras, os benefícios apontados e ressaltados pelo PAFVS podem também ser obtidos.
Objective:
Cardiorespiratory fitness (CRF) reference data for Tibetan (Zang ethnicity) children and adolescents at high altitudes in Tibet of China are lacking. The present study aimed to develop sex- and age-specific 20mSRT norms for Chinese Tibetan children and adolescents at high altitudes.
Method:
A total of 4667 participants from Lhasa (3650 m), Nagqu (4500 m), and Amdo (4700 m) were selected by a stratified random cluster sampling method in two stages. The 20 m SRT test was used to estimate cardiorespiratory fitness. The 20 m SRT norms were developed by the lambda, mu, and sigma method (LMS).
Results:
The 20 m SRT laps, completed stages/minutes, and the speed at the last complete stage of Chinese Tibetan children and adolescents aged 7-18 years increased with age.
Conclusion:
Given the importance of CRF for children and adolescents' health, the government should strengthen the monitoring of the CRF of Tibetan children and adolescents in high-altitude areas, strengthen physical education curriculum reform, and increase the level of physical activity in order to improve the level of CRF in children and adolescents.
Children cope with high temperatures differently than adults do, largely because of slight alterations in their body proportions and heat loss mechanisms compared to fully mature humans. Paradoxically, all current tools of assessing thermal strain have been developed on adults. As the Earth’s warming continues to accelerate, children are set to bear the health risk brunt of rising global temperatures. Physical fitness has a direct impact on heat tolerance, yet children are less fit and more obese than ever before. Longitudinal research reveals that children have 30% lower aerobic fitness than their parents did at the same age; this deficit is greater than can be recovered by training alone. So, as the planet’s climate and weather patterns become more extreme, children may become less capable of tolerating it. This comprehensive review provides an outline of child thermoregulation and assessment of thermal strain, before moving to summarize how aerobic fitness can modulate hyperthermia, heat tolerance, and behavioral thermoregulation in this under-researched population. The nature of child physical activity, physical fitness, and one’s physical literacy journey as an interconnected paradigm for promoting climate change resilience is explored. Finally, future research foci are suggested to encourage continued exploration of this dynamic field, notable since more extreme, multifactorial environmental stressors are expected to continue challenging the physiological strain of the human population for the foreseeable future. © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
The increase in sedentary behavior in children and adolescents has become a worldwide public health problem. This study aimed to explore the associations between sedentary time (ST) and sedentary patterns (SP) and the cardiorespiratory fitness (CRF) of Chinese children and adolescents. The CRF of 535 participants was determined using a 20-m shuttle run test. ST and SP were measured with accelerometers. Questionnaires were used to investigate the different types of ST. Multiple linear regression models were used to test the associations between ST and SP and CRF. In this study, only some ST and SP indicators were found to be significantly associated with CRF in girls. With each additional 10 min of screen time or passive traffic time, VO2max decreases by 0.06 mL/kg/min (B = −0.006, 95% CI: −0.010~−0.001) and 0.31 mL/kg/min (B = −0.031, 95% CI: −0.061~−0.002), respectively, with MVPA control. With each additional 10 min of breaks in ST or duration of breaks in ST, VO2max increases by 0.41 mL/kg/min (B = 0.041, 95% CI: 0.007~0.076) and 0.21 mL /kg/min (B = 0.021, 95% CI: 0.007~0.035), respectively, with control total ST. Breaks in ST (B = 0.075, 95% CI: 0.027~0.123) and the duration of breaks in ST (B = 0.021, 95% CI: 0.012~0.146) were positively correlated with CRF when controlling for LPA, but these associations were not significant when controlling for MVPA (B = 0.003, 95% CI: −0.042~0.048; B = 0.001, 95% CI: −0.024~0.025). The total ST of children and adolescents was found to not be correlated with CRF, but when ST was divided into different types, the screen time and passive traffic time of girls were negatively correlated with CRF. More breaks in ST and the duration of breaks in ST were positively associated with higher CRF in girls. MVPA performed during breaks in ST may be the key factor affecting CRF. Schools and public health departments should take all feasible means to actively intervene with CRF in children and adolescents.
Using the population-based data we aim to estimate the general population trends of multiple components of physical fitness of children, identify critical structural changes in these trends, and evaluate the potential changes in differences in the test scores between the children. During the entire study period, 1989–2019, median body mass index and triceps skinfold increased in both genders and all age groups. Muscular fitness, in general, showed negative trends, with some exceptions: during the post-2010 period, children were mostly experiencing the improvement of isometric strength of the upper body. The neuromuscular components of physical fitness showed positive trends, especially in girls. Cardiorespiratory fitness has been declining in all age groups until the last decade, with the largest decreases occurring before 2000. In the last decade, the trends reversed. The flexibility indicator revealed the largest differences between boys and girls, with boys mainly experiencing negative and girls mostly positive trends. The variability of the test scores mostly increased during the study period. This increasing variance suggests that—despite generally favourable trends in the last decade—children in Slovenia have been facing increasing inequalities in their development, which can potentially lead to future inequalities in health.
We evaluated the effectiveness of a 15-week intervention that increased from three to five lessons of physical education (PE) a week on 7-year-old boys’ and girls’ physical fitness (PF), physical activity (PA) and sedentary behaviour on week and weekend days. A total of 212 first grade pupils (mean age 6.95 ± 0.43) from two urban schools in Poznań were randomly assigned to the experimental or control groups. The PF was measured with a battery of field tests, while health-related behaviours were assessed with the Healthy Children in Sound Communities questionnaire. There were some interaction effects noticed in the PF scores in the case of a 20-min run for boys (F2,196 = 5.29, p = 0.0058) and for girls (F2,220 = 3.31, p = 0.0382) and the sit-ups test for boys (F2,196 = 1.93, p = 0.1478) and for girls (F2,220 = 3.98, p = 0.0201) and for the sit and reach test in the case of girls (F2,220 = 3.98, p = 0.0201). In terms of outdoor PA levels, there were no major differences between any of the examined groups. Differences were found between girls from the experimental and control groups in the post-test (p = 0.0107) and follow-up (p = 0.0390) during the weekdays, with no differences between the groups of boys. Despite the moderate effects of the extended PE time programme right after the intervention, there were some indications of progress in the follow-up experiments.
The present study examined the relationship between peak V̇O 2 and habitual physical activity in 11- to 16-year-old students. The peak V̇O 2 of 111 girls and 85 boys was determined using treadmill or cycle ergometry. Habitual physical activity was estimated from minute-by-minute heart rate monitoring over three 12-hr periods during normal school days. Over half of the girls and one third of the boys failed to sustain a single 10-min period with their heart rate at or above 140 bpm. Only one boy sustained a daily 20-minute period with a heart rate at or above 160 bpm. During Saturday monitoring over 90% of the girls and 75% of the boys failed to sustain a single 10-min period with their heart rate at or above 140 bpm, and only one girl and four boys sustained a 20-min period with their heart rate at or above 160 bpm. No significant relationship was detected between peak V̇O 2 and heart rate indicators of habitual physical activity. This study suggests that few children have periods of physical activity of sufficient intensity and duration to stress the cardiopulmonary system.
The purpose of this study was to determine the validity of using the 1600-m distance run (DR) and the maximal multistage 20-m shuttle run (SR) as predictors of aerobic capacity in active boys 10 to 12 years of age. The influence of weight and maximal sprint running speed on test performance scores were also investigated. Both the DR and SR were found to have concurrent validity in the group studied, correlated to a directly measured VO2max (ml kg−1·min−1) determined through a progressive bicycle ergometer test. However, predicted VO2max values using SR results differed significantly from measured values. Weight was not found to be significantly correlated with either of the predictive methods, whereas maximal sprint running speed, as measured through a 40-m dash, was found to correlate significantly with the results of both the DR and SR. These results suggest that the combined influence of running efficiency and anaerobic energy production significantly influence the performance of both predictive methods.
The assessment and promotion of childrens’ healthful physical activity is important: (i) to combat the international obesity epidemic that extends to childhood; and (ii) to establish an early habit of lifestyle physical activity that can be sustained into adolescence and adulthood. The primary focus of both assessment and promotion efforts has been on in-school physical education classes and, to a lesser extent, out-of-school structured exercise, sport and play. A potential source of continuous moderate activity, active commuting to school by means of walking or by bicycle, has been largely ignored in surveys of physical activity. Suggestive evidence of steep declines in the amount of childrens’ destination walking can be gleaned from national transportation surveys. At the same time, there has been a dramatic increase in the reported use of motorised vehicles, including the use for chauffeuring children. There is very little evidence to support or refute active commuting to school as an important source of childrens’ physical activity; however, this is largely because it has been overlooked in the stampede to assess time in more vigorous activities.
The promotion of active commuting to school must be considered in the context of parents’ real and perceived concerns for their children’s personal and pedestrian safety. We certainly do not have a full understanding at this time of all the factors related to decisions about transportation mode, whether by child, parent, community, or school. Such information is necessary if successful and sustainable interventions can be implemented, important transport policy decisions can be made, and community and school designs can be modified. Practice rarely waits for research, however, and there are numerous examples of innovative programming, policies and environmental designs occurring internationally that can serve as natural experiments for enterprising researchers willing to push the envelope of our understanding of active commuting and childrens’ physical activity. Since we know so little, there is much to learn.
This study examined the reliability and validity of the 20-meter shuttle test as a predictor of peak VO2 in Edinburgh school children. Thirty-three children (15 boys, 18 girls) performed three shuttle tests and three laboratory treadmill tests of peak VO2. Multiple regression analysis revealed that the prediction of peak VO2 (ml·kg−1·min−1) from shuttle run performance was improved by including skinfold thickness measurements in the prediction models, particularly with the female group. Predictive power was greatest for females when using maximal shuttle speed (kmhr−1) best of three repeat tests and triceps skinfold thickness (mm) (R2 = .85, SEE = 2.4), and for males when using maximal shuttle speed (km·hr−1) best of three repeat tests and the sum of the triceps and subscapular skinfolds (R2 = .68, SEE = 3.23). When using shuttle run performance to predict peak VO2 (ml·kg−1·min−1) in children of this age group, body composition measures must be included in the equation.
There is evidence that fitness has been declining and fatness increasing in Australian schoolchildren over the last generation. This study reproduced the methods of a national survey of Australian schoolchildren conducted in 1985. Anthropometric and performance tests were administered to 1,463 10- and Ii-year-old South Australians. Compared to the 1985 sample, the 1997 children were heavier (by 1.4-2.9 kg), showed greater weight for height(by 0.13-0.30 kg.m(-2.85)),and were slower over 1.6 km (by 38-48.5 s). Furthermore, the distribution of values was markedly more skewed in the 1997 data. While there was Little difference between the fittest and leanest quartiles in 1997 and their 1985 counterparts, the least fit and fattest quartiles were markedly worse in 1997. This suggests that the decline in fitness of Australian schoolchildren is not homogeneous and that interventions should target groups where the decline is most marked.
The purpose of the present study was to determine the validity of the 20-meter multistage shuttle run (MSR) for predicting peak VO2 in Hong Kong Chinese students, ages 12–17 years. Fifty-five subjects, 27 boys and 28 girls, performed the MSR in the school environment and had peak VO2 determined in the laboratory. A correlation of 0.72 (p<0.001) was found between peak VO2 and predicted peak VO2 using an equation previously developed with Canadian children (6). However, maximal shuttle run speed alone was a better predictor in this group (r=0.74, SEE=4.6 ml · kg−1·min−1, p<.001). Multiple-regression analysis (best-subsets) was performed and the best predictor variables were maximal speed and sex with either triceps skinfold or weight. For practical application in the school setting, the equation peak VO2 = 24.2 − 5.0(sex) − 0.8(age) + 3.4(maximal speed) (r=0.82, SEE=4.0), where for sex, male = 0 and female = 1, is suggested.