Cardiorespiratory Fitness in Childhood and Adolescence Affects Future Cardiovascular Risk Factors: A Systematic Review of Longitudinal Studies

Lifestyle as a Modulator of the Effects on Fitness of an Integrated Neuromuscular Training in Primary Education

The objective was to evaluate changes in fitness after an integrated neuromuscular training (INT) intervention in primary school children and to evaluate how lifestyle behaviors and parental education modulate these changes. One hundred and seventy children (7.45 ± 0.34 years; 52% girls) were included. Cardiorespiratory fitness (half-mile run test), a 10 × 5 m shuttle run test, standing broad jump (SBJ), handgrip dynamometer, body mass index (BMI) and fat mass percentage (FM%) were assessed before and after the 3-month intervention (20 min of INT in the physical education class, twice per week). The Mediterranean diet (MD), sleep time and parental education level (PEL) were evaluated by questionnaires, and adherence to physical activity (PA) recommendations was measured with a triaxial accelerometer before the intervention. After the intervention, there were improvements in the 10 × 5 test and the SBJ. Only girls had improvements in the handgrip test, BMI SDS and FM%. After correcting for confounding variables, only BMI was significantly improved whereas strength improved in the participants non-compliant with the PA recommendations or pertaining to families of high PEL. The INT produced improvements in fitness in a brief period and in different subgroups of pupils (inactive and with diverse sociocultural environments).

Prepuberty is a window period for curcumin to prevent obesity in postnatal overfed rats

BACKGROUND

Overnutrition in early life increases the risk of obesity and metabolic diseases. We investigated the effects and the window period of a curcumin (CUR) diet on postnatal overfed rats.

METHODS

Male rats aged 3 days were randomly divided into normal litters (NL, 10 pups/litter) and small litters (SL, 3 pups/litter). After weaning (Week 3, W3), NL rats were fed a normal diet (NL) and SL rats were fed a normal diet (SL) or 2% CUR diet from weaning (W3) (SL-CURW13), beginning of puberty (W6) (SL-CURW16), or end of puberty (W8) (SL-CURW18) for 10 weeks.

RESULTS

Body weight, glucose intolerance and hyperlipidemia in the SL rats were higher than in the NL rats, especially after puberty. After the CUR intervention, SL-CURW13 and SL-CURW16 rats showed lower body weight gain, adipose tissue weight and mRNA level of C/EBPα in SAT, along with higher mRNA levels of β-catenin. There was no difference between SL and SL-CURW18 rats. Glucose tolerance, serum lipids and hepatic lipids recovered to normal in the SL-CURW13 rats, but only partially in the SL-CURW16 and SL-CURW18 rats.

CONCLUSION

Prepuberty is a window period for CUR intervention to improve programmed outcomes in postnatal overfed rats.

IMPACT

Overnutrition during the first 1000 days of life has persistent negative effects on metabolism. Strategies should be taken to prevent overnutrition in early life to reduce the risk of obesity and metabolic disease in later life. A small-litter rat model was utilized to simulate early-life overnutrition in humans. We investigated the different effects and critical period for curcumin intervention on postnatal overfed rats. Dietary curcumin intervention before puberty could effectively transform nutritional programming to reduce obesity and metabolic disorders caused by early-life overnutrition, and an earlier intervention might predict a better outcome.

Individual and school correlates of body mass index and cardiorespiratory fitness in primary school children from the REACT project: A multivariate multilevel analysis

OBJECTIVE

This paper examines the relationship between body mass index (BMI) and cardiorespiratory fitness (CRF) using a multivariate multilevel approach and investigates the links between individual and school-related correlates with children's BMI and CRF.

METHODS

This cross-sectional sample included 1014 children (6-10 years) from 25 Portuguese primary schools. BMI was calculated, and CRF was assessed with the PACER test. Fundamental movement skills (FMS) included five object control tasks. Moderate-to-vigorous physical activity (MVPA), sleep, and sedentary time were assessed with the ActiGraph wGT3X-BT accelerometer. Socioeconomic status (SES) and school variables were also obtained. A multivariate multilevel model was used, and alpha was set at 5%.

RESULTS

BMI and CRF systematically increased with age. Most of the joint variance (94.4%) was explained at the child level, and BMI and CRF were correlated at this level (ρ = -.37). More active children demonstrated higher CRF levels and had lower BMI levels; sedentary and sleep time were not significantly associated with BMI or CRF. FMS were positively associated with CRF but were not significantly associated with BMI. Children at higher SES were more fit and had lower BMI than their peers of lower SES. Finally, school-level variables were not significantly related to BMI and CRF.

CONCLUSION

BMI and CRF had a low but statistically significant negative correlation in this sample of children. Most of the variation in BMI and CRF was explained by child-level characteristics.

Influence of Preterm Birth and Low Birthweight on Physical Fitness: A Systematic Review, Meta-Analysis, and Meta-Regression

BACKGROUND

Preterm birth and low birthweight (LBW) might be associated with reduced physical fitness, although evidence remains inconclusive.

OBJECTIVE

To examine the influence of preterm birth and LBW on physical fitness, as well as to assess whether variables such as gestational age, birthweight, or age at assessment moderate these effects.

METHODS

PubMed, Scopus, and PsycINFO were systematically searched from inception to 7 December 2023 for case-control and cohort studies analyzing the association between preterm birth or LBW (or gestational age or birthweight as continuous variables) with at least one physical fitness-related outcome (i.e., cardiorespiratory fitness (CRF), muscle strength, flexibility, speed, agility). Random-effects meta-analysis and meta-regression models were used to estimate the pooled effect size, as well as to examine potential associations between the magnitude of the effect and gestational age, birthweight, or age at assessment.

RESULTS

Fifty-two studies (n = 920,603 participants, average age ranging from 4.7 to 34.4 years) were included. Preterm birth was associated with reduced CRF (standardized mean difference (SMD) = -0.38, 95% confidence interval (CI) = -0.51 to -0.25) and muscle strength (SMD = -0.44, 95% CI = -0.79 to -0.08). LBW was associated with reduced CRF (SMD = -0.40, 95% CI = -0.64 to -0.17), muscle strength (SMD = -0.18, 95% CI = -0.24 to -0.13), flexibility (SMD = -0.11, 95% CI = -0.22 to -0.01), and agility (SMD = -0.99, 95% CI = -1.91 to -0.07). Meta-regression analyses showed that a lower gestational age or birthweight were associated with larger reductions in physical fitness, whereas no consistent association was found for the age at assessment.

CONCLUSION

Both preterm birth and LBW seem associated with reduced physical fitness regardless of age, with larger reductions overall observed in individuals with lower gestational age or birthweight. These findings might support the implementation of preventive strategies (e.g., fitness monitoring and physical exercise interventions) in these populations through the life course. PROSPERO registration: CRD42021231845.

Cardiorespiratory fitness and muscular fitness correlates in youth: A hierarchy of behavioral, contextual, and health-related outcomes

OBJECTIVES

Despite the health importance of identifying correlates of physical fitness in youth, no investigation to date has explored the influence of behavioral, health-related, and contextual correlates simultaneously. We investigated the hierarchical relationship of multiple modifiable correlates favoring or diminishing cardiorespiratory and muscular fitness in youth.

DESIGN

Cross-sectional investigation.

METHODS

In a sample of 5174 children and adolescents, 31 correlates were hierarchized according to their impact on cardiorespiratory and muscular fitness assessed using the FITESCOLA® fitness battery. A Chi-squared Automatic Interaction Detection approach was employed and measures of correlation and association were used to investigate the relationship between physical fitness and correlates.

RESULTS

In children, body mass index was the most relevant factor to discriminate between high and low cardiorespiratory and muscular fitness of the upper, middle, and lower body. While body mass index was more important than any other correlate to differentiate levels of upper and lower body muscular fitness during adolescence, specific characteristics of sports participation emerged as key factors to discriminate between high and low cardiorespiratory fitness and middle body muscular fitness. Other correlates, including the self-report of active recess time, active commuting to school, favorable neighborhood conditions, and limited time on screens and cellphones, were demonstrative of favorable physical fitness levels.

CONCLUSIONS

Both body composition and sports-related characteristics emerged as the two most relevant factors of physical fitness in youth. Additional health benefits may be obtained from building supportive environments for sports and healthy exercise habits within the household and at different school education levels.

Cardiovascular and cardiorespiratory effects of high-intensity interval training in body fat responders and non-responders

This study aimed to investigate cardiovascular and cardiorespiratory adaptations to exercise intervention among participants who showed higher (responders-RSBFP) and lower (non-responders-NRSBFP) levels of body fat percentage (BFP) responsiveness. Adolescents (42.5% males) participated in a ten-week school-based high-intensity interval training (HIIT), followed by a comparison of BFP, blood pressure (BP), and cardiorespiratory fitness (CRF). RSBFP age of 16.15 ± 0.36 years, body height 170.82 ± 8.16 cm, weight 61.23 ± 12.80 kg, and BMI 20.86 ± 3.29 kg/m2. Meanwhile, NRSBFP age of 16.04 ± 0.36 years, body height 168.17 ± 8.64 cm, weight 57.94 ± 8.62 kg, and BMI 20.47 ± 2.24 kg/m2. HIIT intervention impacted BFP, with a higher decrease in the RSBFP than the NRSBFP (ΔBFPRs = - 2.30 ± 3.51(10.34%) vs. ΔBFPNRs = 1.51 ± 1.54(6.96%) p < 0.001). The primary comparison showed a statistically significant interaction effect in relation to CRF (F(1,71) = 14.12; p < 0.001). Detailed comparisons showed large and significant CRF changes in RSBFP (7.52%; d = 0.86; p < 0.001) but not in NRSBFP (2.01%; d = 0.11; p = 0.576). In addition, RSBFP and NRSBFP benefited equally in SBP (5.49%, d = 0.75; p < 0.001; 4.95%, d = 0.74; p < 0.001, respectively). These findings highlight that exercise benefits on body fat may be mainly related to gains in CRF. Due to substantial intra-individual variability in adaptation, there is a need for personalized intervention tailored for those with different reaction thresholds in body mass components.

Exercise blood pressure, cardiorespiratory fitness, fatness and cardiovascular risk in children and adolescents

Cardiovascular disease remains the leading cause of mortality on a global scale. Individuals who possess risk factors for cardiovascular disease, such as high blood pressure (BP) and obesity, face an elevated risk of experiencing organ-specific pathophysiological changes. This damage includes pathophysiological changes in the heart and peripheral vascular systems, such as ventricular hypertrophy, arterial stiffening, and vascular narrowing and stenosis. Consequently, these damages are associated with an increased risk of developing severe cardiovascular outcomes including stroke, myocardial infarction, heart failure, and coronary heart disease. Among all the risk factors associated with cardiovascular disease, high blood pressure emerges as the most prominent. However, conventional resting BP measurement methods such as auscultatory or oscillometric methods may fail to identify many individuals with asymptomatic high BP. Recently, exercise BP has emerged as a valuable diagnostic tool for identifying real (high) blood pressure levels and assessing underlying cardiovascular risk, in addition to resting BP measurements in adults. Furthermore, numerous established factors, such as low cardiorespiratory fitness and high body fatness, have been confirmed to contribute to exercise BP and the associated cardiovascular risk. Modifying these factors may help reduce high exercise BP and, consequently, alleviate the burden of cardiovascular disease. A significant body of evidence has demonstrated cardiovascular disease in later life have their origins in early life. Children and adolescents with these cardiovascular risk factors also possess a greater propensity to develop cardiovascular diseases later in life. Nevertheless, the majority of previous studies on the clinical utility of exercise BP have been conducted in middle-to-older aged populations, often with pre-existing clinical conditions. Therefore, there is a need to investigate further of the factors influencing exercise BP in adolescence and its association with cardiovascular risk in early life. Our previously published work showed that exercise BP is a potential useful method to detect adolescents with increased cardiovascular risk. Children and adolescents with cardiovascular risk factors are more likely to develop cardiovascular diseases later in life. However, previous studies on the clinical utility of exercise BP have largely focused on middle-to-older aged populations with pre-existing clinical conditions. Therefore, there is a need to investigate further the factors influencing exercise BP in adolescence and its association with future cardiovascular risk. Our previous studies, which focused on exercise BP measured at submaximal intensity, have shown that exercise BP is a potentially useful method for identifying adolescents at increased cardiovascular risk. Our previous findings suggest that improving cardio-respiratory fitness and reducing body fatness may help to reduce the risk of developing cardiovascular disease and improve overall cardiovascular health. These findings have important implications for the development of effective prevention and early detection strategies, which can contribute to improved public health outcomes.

Longitudinal Associations Between Enjoyment of Physical Education, Cardiorespiratory Fitness, and Muscular Fitness Among Finnish Adolescents

INTRODUCTION

Students' experiences in physical education (PE) can shape future physical activity (PA) behaviors. PE enjoyment is associated with PA; however, the relationship between PE enjoyment and fitness has not been extensively investigated. The aim of this study was to examine if changes in PE enjoyment were associated with changes in cardiorespiratory fitness (CRF) and muscular fitness (MF) among Finnish adolescents.

METHODS

Study participants were students (n = 1147; 11.27 [±0.32] years at baseline) attending public schools in Finland. Data were collected yearly (2017-2021). The 20 m shuttle run assessed CRF, curl-up/push-up tests assessed MF, and the enjoyment subscale of the Sport Commitment Questionnaire-2 measured PE enjoyment. The random intercept cross-lagged panel model, including repeated measures (within-level) and latent levels (between-level) of PE enjoyment, CRF and MF, was tested. Sex, body mass index, moderate to vigorous PA, and peak height velocity were included as covariates in the analysis.

RESULTS

Over 5 years, PE enjoyment decreased, CRF increased until Timepoint 3, and MF remained stable. Positive associations between PE enjoyment and fitness were observed, indicating the greater the PE enjoyment, the higher the fitness. For PE enjoyment, CRF and MF repeated measures were positively associated with measurement of the next year. PE enjoyment was positively related to CRF and MF the years thereafter.

CONCLUSION

Our findings highlight the importance of quality PE experiences for enjoyment and fitness gains during the transition from primary to secondary school. These findings are important given youth fitness levels are associated with future health status.

Temporal trends and distributional changes in cardiorespiratory fitness among Chinese children and adolescents from 1985 to 2019

OBJECTIVES

The aim of this study was to analyze the temporal trends in cardiorespiratory fitness (CRF) and body mass index (BMI) among children and adolescents from 1985 to 2019.

METHODS

A total of 1 840 212 children and adolescents aged 7-18 years (921 223 boys) were tested for CRF from 1985 to 2019. CRF was tested by 50-m × 8 shuttle run for boys and girls aged 7-12 years, 1000-m run for boys aged 13-18 years, and 800-m run for girls aged 13-18 years. Trends in BMI from 2000 to 2019 were also investigated.

RESULTS

Cardiorespiratory fitness decreased during the entire 34 years among children and adolescents in all sex and age categories, and the most rapid decline occurred from 1995 to 2005. Some positive trends in CRF were observed among adolescents aged 13-15 years from 2005 to 2019 and among girls aged 16-18 years from 2014 to 2019. The variation in the CRF distribution was not uniform, with Z-scores for participants with high CRF levels changing little or increasing (CRF stabilized or improved) and Z-scores for participants with low CRF levels continuing to decrease (CRF decreased). BMI increased over time for boys and girls in all age categories, with an acceleration of the increase for adolescents in recent years.

CONCLUSIONS

This study revealed that the overall CRF levels of Chinese children and adolescents decreased over three decades but stabilized or improved in recent years. BMI continued to increase. Our findings are important for the focus on future domestic physical fitness and public health.

Association between time of assessment within a school year and physical fitness of primary school children

The dissociation of effects of age, time of assessment and cohort is a well-known challenge in developmental science. We examined effects of time of assessment in the school year on children's physical fitness using data from 75,362 German third-graders from seven cohorts. Children were tested once either in the first or second school term of third grade. Tests examined cardiorespiratory endurance (6-min run), coordination (star-run), speed (20-m sprint), lower (standing long jump) and upper (ball-push test) limbs muscle power, and flexibility (stand-and-reach test). We estimated the effect of time of assessment using a regression discontinuity design specified in a linear mixed model with random factors child and school and adjusted for age, sex, and cohort effects. Coordination, speed, and upper limbs muscle power were better in second compared to first school term, with boys exhibiting a larger increase of upper limbs muscle power than girls. There was no evidence for changes in cardiorespiratory endurance, lower limbs muscle power, and flexibility between assessments. Previously reported age and sex effects as well as secular fitness trends were replicated. There is thus evidence for improvement of some physical fitness components beyond age and cohort effects that presumably reflects the benefit of physical activity in physical education and other settings. Effects of assessment time should be taken into consideration in performance-based grading or norm-based selection of children.

Trajectories of osteogenic physical activity in children and adolescents: A 3-year cohort study

OBJECTIVES

We explored the latent profiles based on locomotor skills and cardiorespiratory fitness in Finnish schoolchildren and examined their associations with latent growth curves of osteogenic physical activity (PA) over three years.

DESIGN

Prospective cohort study.

METHODS

Altogether 1147 Finnish adolescents aged 11-13 years participated in the study. Osteogenic PA in terms of osteogenic index (OI) was calculated based on acceleration peak histograms using all of the peaks with acceleration >1.3 g. Locomotor skills were assessed using the five-leap and side-to-side jumping tests and cardiorespiratory fitness (CRF) using 20-metre shuttle run test. The latent growth curve models for the locomotor skills and cardiorespiratory fitness profiles were tested to examine the longitudinal development of OI scores over time three years (from T0 to T3).

RESULTS

OI scores were lower amongst children in the "Low locomotor profile" compared with "Moderate" and "High locomotor" profiles. The OI scores linearly decreased from T0 to T3 in each locomotor profile and the decrease was similar in all the profiles. Moreover, OI scores were lower in the "Low CRF profile" compared with "Moderate" and "High CRF" profiles. The OI scores decreased in each profile over time, but the decrease was steepest in the "Low CRF profile", whereas "Moderate" and "High CRF profiles" had similar developmental trajectories.

CONCLUSIONS

Children with the highest locomotor skills and higher CRF accumulate more osteogenic PA than their least skilful and fit peers, which can have important implications on bone health in this critical period for bone growth.

The Longitudinal Association of Cardiorespiratory Fitness and Adiposity With Clustered Cardiometabolic Risk: A Mediation Analysis

PURPOSE

Previous literature has demonstrated the mediating role of adiposity in the association between cardiorespiratory fitness (CRF) and cardiometabolic risk as well as the potential role of CRF in attenuating the adverse consequences associated with excess weight. This study aimed to evaluate the mediating role of CRF and adiposity in the possible association with cardiometabolic risk.

METHOD

Observational 3-year longitudinal study that included 420 children and adolescents (10.50 [2.05] y of age at baseline; 56.2% girls). Body mass index (BMI) was calculated, and CRF was evaluated using field assessments. A clustered cardiometabolic risk score (cMetS) was calculated from glucose, systolic blood pressure, total cholesterol/high-density lipoprotein cholesterol ratio, and triglycerides z scores. Analyses evaluated the mediating role of BMI in the association between CRF and cMetS as well as whether CRF mediated the association between BMI and cMetS.

RESULTS

BMI at baseline was directly associated with the cMetS at follow-up (0.102; 95% confidence interval, 0.020 to 0.181), independently of CRF, whereas CRF was only indirectly associated with cMetS at follow-up through BMI (-0.036; 95% confidence interval, -0.070 to -0.009), meaning that the association between CRF and cMetS was explained via the mediation role of BMI.

CONCLUSIONS

BMI presented direct association with cMetS, whereas CRF exhibited indirect association with cMetS mediated via BMI.

The concurrent validity and test-retest reliability of a submaximal exercise test in adolescents with autism

PURPOSE

There is a need for valid and reliable clinical assessment tools to assess cardiorespiratory fitness (CRF) levels in adolescents with autism. Therefore, this study aimed to examine the concurrent validity and test-retest reliability of the Astrand-Rhyming Test (ART) in this population.

MATERIALS AND METHODS

45 adolescents with autism aged 12-18 years (n = 32 males, 14.47 ± 1.79 years) performed the ART twice (test-retest reliability) and completed a maximal cardiopulmonary exercise test (CPET) (concurrent validity). Reliability parameters included Pearson correlations, intraclass correlation coefficients (ICCs), standard error of measurements (SEM), minimal detectable changes (MDC), coefficients of variation, paired sample t-tests, linear regressions and Bland-Altman plots. The concurrent validity was evaluated with Pearson correlations, ICCs, paired sample t-tests, linear regressions and Bland-Altman plots.

RESULTS

Strong test-retest reliability (r = 0.84-0.85, ICC = 0.84-0.85) was found for the ART, but the wide limits of agreement intervals suggest the presence of substantial variability. The large SEM (4.73-5.08 mL/kg/min) and MDC (13.20-14.07 mL/kg/min) values suggest lower absolute reliability. Moderate to strong levels of association (r = 0.74-0.75) and agreement (ICC = 0.59-0.66) were found between estimated (ART1) and measured (CPET) VO2 max levels, but significant systematic differences (5.71-8.82 mL/kg/min) were observed.

CONCLUSION

The ART is an accessible and promising method to monitor submaximal CRF levels over time but is less appropriate to estimate maximal CRF levels in this population.

A Coordinated School Health Program Effect on Cardiorespiratory Fitness of South Texas Preschool Children: A Cluster Randomized Trial

BACKGROUND

The purpose of this study was to assess the effects of the Bienestar/NEEMA Coordinated School Health Program (BN CSHP) on cardiorespiratory fitness (CRF) of preschool children.

METHODS

A cluster randomized trial was conducted of preschools in South Texas. Of 48 eligible schools, 28 were randomly assigned (14 intervention, 14 control). Family demographics and household health characteristics were collected from parents and CRF from children. Generalized linear mixed model (GLMM) was used to analyze the data.

RESULTS

Family demographics, household health characteristics, and children's weight, obesity prevalence, and sedentary activity of the control group were similar to the intervention group at baseline. After adjusting for covariates, the number of laps ran by children in the control group increased by 23% (CI: -5% to 60%) per each data collection period compared with 53% (CI: 7% to 119%) in the intervention group.

IMPLICATIONS FOR SCHOOL HEALTH POLICY, PRACTICE, AND EQUITY

State mandates, parent engagement, and funding are key for designing effective health and Physical Education (PE) programs.

CONCLUSION

Children in the BN CSHP, compared to those in the control group, had a significantly higher increase in their CRF. This finding is important because of the health benefits of CRF in children.

CLINICALTRIALS

gov Identifier: NCT05501392.

Reliability of field- and laboratory-based assessments of health-related fitness in preschool-aged children

OBJECTIVES

Reliable measurements of health-related fitness-cardiorespiratory endurance, muscular endurance, muscular strength, body composition, and flexibility-are imperative for understanding and tracking health-related fitness from the preschool age. This study aimed to examine the test-retest reliability of field-based (i.e., sit and reach [standard and back-saver], standing long jump, grip strength); and laboratory-based (i.e., Bruce Protocol Treadmill Test, Wingate Anaerobic Test) assessments of health-related fitness in preschool aged children (4-5 years).

METHODS

Forty-two typically developing children participated in both assessment time points separated by 2-3 weeks. All fitness assessments were administered individually and repeated in the same order by the same assessor. Heteroscedasticity was examined for each parameter. Intraclass correlation coefficients were calculated to assess test-retest reliability.

RESULTS

All parameters were homoscedastic. Test-retest reliability for the field-based tests and Bruce Protocol Treadmill Test parameters were moderate to good. Test-retest reliability for the Wingate Test parameters were good to excellent for maximum pedal rate, peak power, and peak power/kg; mean power and fatigue measured at 10 and 30 s demonstrated moderate to excellent test-retest reliability.

CONCLUSION

The standard sit and reach, grip strength, and short-term muscle power from the Wingate test are reliable assessments of health-related fitness in preschool-aged children.

A Reference Equation for Peak Oxygen Uptake for Pediatric Patients Who Undergo Treadmill Cardiopulmonary Exercise Testing

Pediatric patients are often referred to cardiopulmonary exercise testing (CPET) laboratories for assessment of exercise-related symptoms. For clinicians to understand results in the context of performance relative to peers, adequate fitness-based prediction equations must be available. However, reference equations for prediction of peak oxygen uptake (VO2peak) in pediatrics are largely developed from field-based testing, and equations derived from CPET are primarily developed using adult data. Our objective was to develop a pediatric reference equation for VO2peak. Clinical CPET data from a validation cohort of 1,383 pediatric patients aged 6 to 18 years who achieved a peak respiratory exchange ratio ≥1.00 were analyzed to identify clinical and exercise testing factors that contributed to the prediction of VO2peak from tests performed using the Bruce protocol. The resultant prediction equation was applied to a cross-validation cohort of 1,367 pediatric patients. Exercise duration, gender, weight, and age contributed to the prediction of VO2peak, generating the following prediction equation: (R2 = 0.645, p <0.001, standard error of the estimate = 6.19 ml/kg/min): VO2peak (ml/kg/min) =16.411+ 3.423 (exercise duration [minutes]) - 5.145 (gender [0 = male, 1 = female]) - 0.121 (weight [kg]) + 0.179 (age [years]). This equation was stable across the age range included in the present study, with differences ≤0.5 ml/kg/min between mean measured and predicted VO2peak in all age groups. In conclusion, this study represents what we believe is the largest pediatric CPET-derived VO2peak prediction effort to date, and this VO2peak prediction equation provides clinicians who perform and interpret exercise tests in pediatric patients with a resource with which to better quantify fitness when CPET is not available.

Sleep duration and cardiorespiratory fitness in adolescents: Longitudinal analysis from the LabMed study

PURPOSE

We aimed to investigate longitudinal associations between sleep duration and cardiorespiratory fitness, in adolescents.

METHODS

Sleep duration was self-reported and cardiorespiratory fitness was assessed by the 20 m shuttle run test, both at baseline and follow-up (2-year follow-up). Participants were 734 Northern Portuguese adolescents (349 girls), aged 14.6 ± 1.8 years, from the LabMed study.

RESULTS

Significant decreases were found between baseline and follow-up for sleep duration, whereas for cardiorespiratory fitness there was an increase. Adolescents with short sleep duration at baseline had lower cardiorespiratory fitness at follow-up, comparing to those meeting the sleep guidelines (odds ratio [OR] = 0.506, 95% confidence interval [CI]: 0.326-0.785; p = .002 for whole week; OR = 0.597, 95% CI: 0.407-0.875; p = .008 for weekdays). Girls who were short sleepers at baseline had lower odds of having a healthy cardiorespiratory fitness at follow-up, comparing to those meeting the sleep guidelines (OR = 0.311, 95% CI: 0.158-0.613; p < .001 for whole week; OR = 0.469, 95% CI: 0.262-0.838; p = .011 for weekdays). No significant associations between sleep duration and cardiorespiratory fitness were found for boys.

DISCUSSION

There was a significant longitudinal association between short sleep duration and lower cardiorespiratory fitness levels, particularly in girls. Future interventions targeting adolescents' sleep duration should acknowledge behavioral differences between genders, as well as different behaviors adopted by boys ang girls, specifically on weekends.

Effects of a physical education intervention on children's physical activity and fitness: the PROFIT pilot study

BACKGROUND

Physical education classes are widely accepted as one of the most effective settings for promoting physical activity and health and have often been used to implement physical activity interventions. The aim of this pilot study was to test a physical education intervention program on physical activity levels and physical fitness in a sample of school-age children.

METHODS

Participants were a convenience sample of 50 children (34 experimental group and 16 in the comparative group) aged between 6 and 11 years old (Mean = 8.28 years). A 21-week intervention was implemented, consisting of high-intensity and physical fitness-focused exercises, in addition to a once-a-month extra class nutritional education. The following variables were evaluated before and post-intervention: physical fitness, sedentary behavior (SB), light physical activity (LPA), moderate physical activity (MVA), and vigorous physical activity (VPA). Propensity score analyses calculated the average treatment effect on the treated (ATET) within a quasi-experimental framework.

RESULTS

Physical fitness variables showed improvements after the intervention, specifically for agility (ATET = -0.67 s; p < 0.001), cardiorespiratory fitness (ATET = 89.27 m; p = 0.045), lower limbs power (ATET = 4.47 centimeters; p = 0.025), and speed (ATET = -1.06 s; p < 0.001). For physical activity and SB levels, there were no improvements after intervention implementation.

CONCLUSION

The intervention program showed preliminary effectiveness to improve physical fitness of children, but not SB nor physical activity.

Associations between physical fitness and cerebellar gray matter volume in adolescents

Despite the importance of the developing cerebellum on cognition, the associations between physical fitness and cerebellar volume in adolescents remain unclear. We explored the associations of physical fitness with gray matter (GM) volume of VI, VIIb and Crus I & II, which are cerebellar lobules related to cognition, in 40 (22 females; 17.9 ± 0.8 year-old) adolescents, and whether the associations were sex-specific. Peak oxygen uptake (V̇O2peak ) and power were assessed by maximal ramp test on a cycle ergometer, muscular strength with standing long jump (SLJ), speed-agility with the shuttle-run test (SRT), coordination with the Box and Block Test (BBT) and neuromuscular performance index (NPI) as the sum of SLJ, BBT and SRT z-scores. Body composition was measured using a dual-energy X-ray absorptiometry. Cerebellar volumes were assessed by magnetic resonance imaging. V̇O2peak relative to lean mass was inversely associated with the GM volume of the cerebellum (standardized regression coefficient (β) = -0.038, 95% confidence interval (CI) -0.075 to 0.001, p = 0.044). Cumulative NPI was positively associated with the GM volume of Crus I (β = 0.362, 95% CI 0.045 to 0.679, p = 0.027). In females, better performance in SRT was associated with a larger GM volume of Crus I (β = -0.373, 95% CI -0.760 to -0.028, p = 0.036). In males, cumulative NPI was inversely associated with the GM volume of Crus II (β = -0.793, 95% CI -1.579 to -0.008 p = 0.048). Other associations were nonsignificant. In conclusion, cardiorespiratory fitness, neuromuscular performance and speed-agility were associated with cerebellar GM volume, and the strength and direction of associations were sex-specific.

Reference Values for Cardiorespiratory Fitness in Patients Aged 6 to 18 Years

OBJECTIVE

To develop reference values for cardiorespiratory fitness, as quantified by peak oxygen uptake (VO2peak) and treadmill time, in patients aged 6 through 18 years referred for cardiopulmonary exercise testing (CPET).

STUDY DESIGN

We reviewed a clinical pediatric CPET database for fitness data in children aged 6-18 years with no underlying heart disease. CPET was obtained via the Bruce protocol utilizing objectively confirmed maximal effort via respiratory exchange ratio. Fitness data (VO2peak and treadmill test duration) were analyzed to determine age- and sex-specific reference values for this pediatric cohort.

RESULTS

Data from 2025 pediatric CPETs (53.2% female) were included in the analyses. VO2peak increased with age in males, but not females. Treadmill test duration increased with age in both males and females. Fitness was generally higher in males when compared with females in the same age groups.

CONCLUSIONS

Our study provides extensive reference values for both VO2peak and total treadmill test time via the Bruce protocol for a pediatric population without known cardiac disease. Furthermore, the inclusion of objectively confirmed maximal exercise effort increases confidence in these findings compared with prior studies in this area. Clinicians performing CPET in pediatric populations can utilize these reference values to characterize test results according to representative peer data.

Effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness: A multi-country cluster randomized controlled trial

PURPOSE

To examine the effects of a school-based karate intervention on academic achievement, psychosocial functioning, and physical fitness in children aged 7-8 years.

METHODS

Twenty schools in 5 different European countries (2 second-grade classrooms per school) participated in a cluster randomized controlled trial (Sport at School trial). Participants were assigned to either a control group, which continued with their habitual physical education lessons, or to an intervention group, which replaced these lessons with a 1-year karate intervention (Karate Mind and Movement program). A total of 721 children (344 girls and 377 boys, 7.4 ± 0.5 years old, mean ± SD) completed the study, of which 333 and 388 were assigned to the control group and intervention group, respectively. Outcomes included academic performance (average grade), psychosocial functioning (Strengths and Difficulties Questionnaire for parents), and different markers of physical fitness (cardiorespiratory fitness, balance, and flexibility).

RESULTS

The intervention provided small but significant benefits compared to the control group for academic achievement (d = 0.16; p = 0.003), conduct problems (d = -0.28; p = 0.003), cardiorespiratory fitness (d = 0.36; p < 0.001), and balance (d = 0.24; p = 0.015). There was a trend towards significant benefits for flexibility (d = 0.24; p = 0.056). No significant benefits were observed for other variables, including psychosocial difficulties, emotional symptoms, hyperactivity/inattention, peer problems, or prosocial behaviour (all p > 0.05).

CONCLUSION

A 1-year school-based karate intervention was effective in improving academic achievement, conduct problems, and physical fitness in primary school children. The results support the inclusion of karate during physical education lessons.

The association of adolescent fitness with cardiometabolic diseases in late adulthood: A 45-year longitudinal study

OBJECTIVES

The aim of this study was to examine the associations of adolescent cardiorespiratory fitness (CRF), muscular fitness (MF), and speed-agility fitness (SA) with middle-aged cardiometabolic disease risk and explore sex differences.

METHODS

This 45-year prospective cohort study examined the associations between objectively measured fitness at adolescence (12-19 years) and physician-ascertained diabetes mellitus, elevated blood pressure (BP), and coronary heart disease reported either in early (37-44 years) or late (57-64 years) middle age, and self-measurement of waist circumference (WC) in late middle age. Fitness measurements for healthy adolescents in baseline included CRF (1.5 km [girls] and 2 km [boys] run), MF (standing broad jump, sit-ups, pull-ups [boys], and flexed-arm hang [girls]), and SA (50 m dash and 4 × 10 m shuttle run). Logistic regression and general linear models were adjusted for baseline age, sex, and body mass index (BMI), involving data from baseline and at least one follow-up measurement (N up to 1358, 47% males).

RESULTS

Adolescent CRF was inversely, and regardless of adiposity, associated with middle age accumulated burden of cardiometabolic conditions in the whole sample (N = 562, ß = -0.10, 95% confidence intervals [CI] [-0.18, -0.03], p = 0.006), and elevated BP in females (N = 256, OR = 0.71, 95% CI [0.51, 0.91]). Overall, we observed stronger associations in females than in males. An inverse association of adolescent MF and SA with middle-aged WC was observed, but it did not show as consistent associations as with CRF.

CONCLUSIONS

In this study, adolescent fitness, particularly CRF, was inversely associated with the burden of cardiometabolic conditions up to 45 years. Promotion of fitness in youth may be beneficial in preventing adulthood cardiometabolic diseases.

The Effects of Using a Cycling Desk at School on Executive Function, Physical Fitness, and Body Composition in Primary School Children: Impact of Socioeconomic Status

CONTEXT

Physical inactivity and sedentary behaviors are associated with adverse health outcomes in both adults and children. The purpose of this study was to investigate the effects of a 9-week program using a Cycle Desk during school time in French primary school children from high or low socioeconomic status (SES) on body composition, physical fitness (PF), and executive function.

METHODS

Seventy-five (n = 75) children completed a test battery before and after 9 weeks of use of Cycle Desk to evaluate anthropometric characteristics, body composition, PF, and executive function.

RESULTS

Body mass index increased significantly (P = .0095), while body fat decreased after the use of Cycle Desks (P < .0001). Specifically, lean mass increased in the high-SES group while it decreased in the low-SES group (P < .0001). After 9 weeks, there was an improvement in motor skills (P < .0001), upper and lower limbs' strength (P < .0001), and executive function performance (P < .0001). More specifically, the low-SES group had a greater improvement in motor skills and maximal aerobic speed between T0 and T1, compared to the high-SES group (P = .001, P = .023, respectively). In contrast, the high-SES group had a greater improvement in executive function at 9 weeks of use of Cycle Desk compared with the low-SES group (P = .0084).

CONCLUSIONS

The promotion of low-intensity physical activity with the use of a Cycle Desk at school may help offset some adverse effects of excess sedentary behavior among children. Moreover, this strategy appears to be particularly effective in children from low-SES backgrounds. What's New: The use of a Cycle Desk during school time has no deleterious effects on PF as well as cognitive executive functions in primary children. Modifications are more beneficial in children from low SES.

Primary school children's health and its association with physical fitness development and health-related factors

The health status (HS) of children is influenced by a variety of factors, including physical fitness (PF) or social and environmental characteristics. We present a 4-year longitudinal study carried out with 263 primary school children. PF was assessed yearly using the German Motor Performance Test 6-18. Demographic data, leisure time behavior and socioeconomic factors were collected using questionnaires for children and parents. Based on parents' ratings in year 4, children were categorized as either "very good health status" (VGHS) or "good health status or below" (GHSB). Children with VGHS (73%) showed a larger improvement of global PF (p < 0.001), a significantly higher proportion of being/playing outside (p < 0.001), significantly lower proportions of overweight (p < 0.001), of media availability in the bedroom (p = 0.011) and of daily media consumption > 2 h (p = 0.033) compared to children with GHSB. Regarding socio-economic factors, children with VGHS revealed significantly fewer parents with lower education (p = 0.002), lower physical activity levels (p = 0.030) and lower migration background (p < 0.001). Physical fitness (p = 0.019) and outdoors exercising (p = 0.050) were the only variables to provide significantly higher chances of perceiving one's own health as very good when tested within a complex model including all the variables studied in this work. Considering the little focus on PF in the current Austrian physical education curriculum and the favorable environmental features of the Tyrolean region, more emphasis should be given to promoting didactical and pedagogical approaches that allow schoolers to be active in the nature.

Assessment of Cardiorespiratory Fitness in 8-to-15-Year-Old Children with Overweight/Obesity by Three-Minute Step Test: Association with Degree of Obesity, Blood Pressure, and Insulin Resistance

OBJECTIVE

To assess cardiorespiratory fitness in children and adolescents with overweight/obesity using the Kasch pulse recovery (KPR) test, and its correlation with severity of obesity, insulin resistance, and blood pressure (BP).

METHODS

This is a retrospective analysis of baseline data from a study evaluating the efficacy of yoga for reduction of body mass index (BMI) in children aged 8-15 y with overweight/obesity. KPR three-minute step test was done. Children were classified into cardiorespiratory fitness categories based on the post-KPR heart rate (HR); the maximal oxygen consumption (VO2 max) was calculated, and the correlation analysis was done.

RESULTS

One hundred fifty-five children with mean age of 11.6 ± 1.8 y and mean BMI of 26.2 ± 4.1 kg/m2 were included. Mean post-KPR-HR and calculated VO2 max were 119 ± 14 per minute and 48.7 ± 5.6 mL/kg/min, respectively. In children < 13 y, cardiorespiratory fitness was excellent or very good in 28%, good or sufficient in 58%, and poor or very poor in 14%. BMI, waist circumference (WC), resting HR, systolic BP, and homeostatic model of insulin resistance (HOMA-IR) were higher among those with poor/very poor fitness, with WC z score being statistically significant (p = 0.015). Post-KPR-HR showed positive correlation with BMI z score (r = 0.16, p = 0.044), WC z score (r = 0.21, p = 0.011), and HOMA-IR (r = 0.22, p = 0.012).

CONCLUSION

In children with overweight/obesity, 14% had poor cardiorespiratory fitness. Post-KPR-HR and calculated VO2 max had good correlation with measures of obesity and HOMA-IR. Further studies evaluating cardiorespiratory fitness and normative data of VO2 max for Indian children are warranted.

Short-Term Impact of Exercise Fitness Testing in a Pediatric Metabolic and Obesity Clinic: Initiative to Improve Health Care Quality

This 2-phase pilot initiative determined whether (1) fitness testing could feasibly be implemented in pediatric practice, and (2) short-term changes in fitness and body mass index occur with Specific, Measurable, Attainable, Relevant, and Time-based (SMART) goals. Phase 1 (N = 580), clinic feasibility: evidence-based prognostic tests were successfully performed to measure cardiorespiratory fitness (CRF; 3-minute bench step), strength (handgrip dynamometry), and flexibility (sit-and-reach distance). Mean CRF percentile was 58.1 (worst >95 percentile, best <5 percentile), strength percentile was 73.5, and flexibility was 42.3 (worst <5 percentile, best >95 percentile). Phase 2, goal setting and follow-up: SMART fitness goals were developed. In phase 2, patients demonstrated 11.9% and 12.4% improvements in CRF and strength percentiles (P < .05) respectively. All patients who were assigned a strength goal improved handgrip strength. Body mass index percentile changes were not different by SMART goal target. Fitness testing was feasible and successfully improved CRF and strength in children at high risk of metabolic complications and future disability.

Current situation and factors influencing physical fitness among adolescents aged 12 ∼ 15 in Shandong Province, China: A cross-sectional study

Adolescent physical fitness serves not merely as a current barometer of well-being but as a significant prognosticator of future health trajectories. Amidst the tumult of socioeconomic metamorphoses and pronounced lifestyle transitions enveloping China-mirroring global trends-the imperative to elucidate the present landscape of adolescent physical fitness intensifies. Moreover, discerning the myriad determinants underpinning it becomes paramount. In this context, our research endeavored to meticulously delineate the physical fitness milieu of adolescents residing in Shandong Province, systematically unpacking the multifarious influencers thereof. The insights garnered herein furnish an empirical foundation, primed to guide the sculpting of calibrated interventions, targeting the enhancement of health in this pivotal population cohort. In an extensive evaluative survey conducted in 2023 concerning the physical fitness of Shandong's student populace, a cohort of 33,211 adolescents aged 12 to 15 years was delineated utilizing a stratified random cluster sampling technique. This exercise meticulously quantified the physical fitness indices across diverse gender, age, and household registration classifications, subsequently computing the concomitant qualified rates. Employing multivariable logistic regression analysis, this investigation delved into the determinants modulating the adolescents' physical fitness qualified rate. For 2023, the aggregate fitness qualified rate stood at 91.94 % for the adolescents aged 12 ∼ 15 in Shandong Province. Gender-wise, female adolescents registered a qualified rate of 92.25 %, marginally eclipsing their male peers at 91.63 % (P < 0.05). An age-related trend in qualified rates was discernible, with marked variations across different age bands (P < 0.05): 91.37 % for 12-year-olds, 91.79 % for 13-year-olds, 91.81 % for 14-year-olds, and a zenith of 92.87 % for 15-year-olds. A geographical dichotomy emerged wherein rural adolescents distinctly outperformed their urban counterparts, notching up a 92.28 % qualified rate versus 91.64 % in urban settings (P < 0.05). The multivariable logistic regression analysis showed that after adjusting for gender, age, and household registration characteristics, adolescents had a lower odds of failing the physical fitness tests whose parents both liked physical exercises, whose parents supported children's participation in physical exercise, who participated in physical exercise sessions 3 ∼ 5 times per week or more than 5 times per week, who exercised for 0.5 ∼ 1 h each time or more than 1 h each time, who engaged in moderate intensity physical exercise, who slept 6 ∼ 8 h per day or more than 8 h per day, who consumed breakfast 3 ∼ 6 times per week or daily. On the other hand, adolescents had a higher odds of failing the physical fitness tests who always exposed to passive smoking, who spent 1 ∼ 3 h on screen per day or more than 3 h on screen per day, who spent more than 3 h doing homework per day, who consumed fast food 2 ∼ 3 times per week or more than 3 times per week. The physical fitness trajectory of adolescents residing within Shandong Province is tethered to a mosaic of determinants. This underscores the imperative for a synergistic strategy, harmonizing parental, scholastic, and societal vectors, to cultivate the salubrious maturation of this pivotal cohort.

A synthesis of pathways linking diet, metabolic risk and cardiovascular disease: a framework to guide further research and approaches to evidence-based practice

Cardiovascular disease (CVD) is the most common non-communicable disease occurring globally. Although previous literature has provided useful insights into the important role that diet plays in CVD prevention and treatment, understanding the causal role of diets is a difficult task considering inherent and introduced weaknesses of observational (e.g. not properly addressing confounders and mediators) and experimental research designs (e.g. not appropriate or well designed). In this narrative review, we organised current evidence linking diet, as well as conventional and emerging physiological risk factors, with CVD risk, incidence and mortality in a series of diagrams. The diagrams presented can aid causal inference studies as they provide a visual representation of the types of studies underlying the associations between potential risk markers/factors for CVD. This may facilitate the selection of variables to be considered and the creation of analytical models. Evidence depicted in the diagrams was systematically collected from studies included in the British Nutrition Task Force report on diet and CVD and database searches, including Medline and Embase. Although several markers and disorders linked to conventional and emerging risk factors for CVD were identified, the causal link between many remains unknown. There is a need to address the multifactorial nature of CVD and the complex interplay between conventional and emerging risk factors with natural and built environments, while bringing the life course into the spotlight.

Physical fitness among children with diverse weight status during and after the COVID-19 pandemic: a population-wide, cohort study based on the Slovenian physical fitness surveillance system (SLOfit)

Background

COVID-19 public health crisis has exerted immediate negative impacts on children's physical fitness, but the longer-term effects are not clear, and the impact on children with excess weight is yet unknown. We examined changes in multiple components of physical fitness in response to COVID-19 imposed restrictions, but also a year after the restrictions were terminated, and compared these trends in groups of boys and girls with normal weight, overweight, or obesity before the pandemic.

Methods

Information was gathered through Slovenia's national fitness surveillance system, and included 41,330 children (19,890 girls), aged 5-17, who had their fitness levels measured yearly from 2019 to 2022. Multilevel linear mixed models, fitted separately for boys and girls, were used to model the individual-level trends over time in centile score for each fitness test across 3 weight groups.

Findings

Overall fitness levels decreased markedly across all weight categories between 2019 and 2020, with the largest decreases in Total Fitness Index observed in children with normal weight and overweight (-8.4 and -7.7 centiles for boys and -8.3 and -8.8 for girls, respectively, p < 0.001). While there was some recovery in the overall fitness level between 2020 and 2022, it remained much lower in 2022 compared to 2019 across most groups, apart from boys with obesity. Fitness components that had the largest impact on general fitness trends were cardiorespiratory fitness, lower body power, body core, and upper body strength.

Interpretation

A severe decline in fitness that has not come close to returning to pre-pandemic levels in most population groups of youth begs for urgent population-wide initiatives that will provide additional opportunities for physical activity to youth. Among vulnerable groups, girls with overweight and obesity deserve a special focus of these policies.

Funding

Horizon 2020 (Grant no. 774548), Slovenian National Research Agency (Grant no. P5-0142), Croatian Science Foundation (Grant no. DOK-2020-01-3728).

Association between physical fitness and normal weight obesity in children and adolescents from Poland

OBJECTIVES

Normal weight obesity (NWO) is defined as elevated adiposity, despite normal body mass index (BMI). The aim of this study was to compare the results of selected fitness parameters in Polish children and adolescents from Poland with and without normal weight obesity.

METHODS

The study was cross-sectional and school-based. Body height, weight and adiposity, as well as the results of selected fitness tests, were obtained. BMI was calculated, and only normal-weight individuals were included. NWO was defined as normal BMI with adiposity ≥85 percentile for age and sex.

RESULTS

Children with NWO tended to have better results of absolute dynamometric strength and overhead medicine ball throw. On the other hand, when the dynamometric strength was normalized for the body mass nonNWO group achieved better results. Furthermore, NWO group had lower explosive muscle strength of the lower limbs, agility, as well as abdominal muscle strength, and endurance.

CONCLUSIONS

Obtained results suggest that NWO is associated with a decrease in at least some fitness parameters in children and adolescents. Therefore, it can be hypothesized, that normal weight obesity can result in poorer fundamental motor skills. Moreover, as parameters such as muscle strength have been shown to be associated with cardiometabolic risks, described results can also be important in the context of the present and future health of the children. The results also highlight the importance of monitoring physical fitness and body composition in children, as individuals with NWO are almost indistinguishable from normal weight non-obese counterparts based on current standard surveillance protocols.

Influence of preterm birth on physical fitness in early childhood

Evidence suggests that preterm birth is associated with an impaired physical fitness later in life, but whether these effects are already visible since early childhood remains unknown. We aimed to compare the physical fitness of preterm preschoolers with that of children born at term. Children aged three to six years and born preterm (<35 weeks) were recruited from a Neonatal Intensive Care Unit, and children born at term (>37 weeks) were included as controls. A variety of physical fitness indicators (strength, cardiorespiratory fitness, agility, flexibility and balance) were assessed with the PREFIT battery and the adapted sit and reach test. Physical activity levels were measured through the PrePAQ questionnaire. A total of 98 preterm children (gestational age 32.4 ± 2.3 weeks, age 5.1 ± 0.8 years) and 74 controls (gestational age 39.9 ± 1.0 weeks, age 4.8 ± 0.9 years) were analysed. Despite no significant differences in physical activity levels (p > 0.05), preterm children showed an overall poorer physical fitness compared to controls. Specifically, preterm children had an impaired handgrip strength (-13.95%, p < 0.001), lower-limb muscle strength (-12.67%, p = 0.003), agility (-14.9%, p = 0.001), cardiorespiratory fitness (-12.73% p = 0.005) and flexibility (-17.04%, p = 0.001) compared to controls. An inverse dose-response association was observed between the level of prematurity and physical fitness, with very preterm children (gestational age ≤32 weeks) presenting the poorest fitness levels. In summary, prematurity seems to impair physical fitness since early childhood, which might support the need for promoting preventive strategies (e.g. fitness monitoring and applying exercise interventions).Highlights Preterm children present an impaired physical fitness compared with peers born at term since early childhood (3-6 years), as reflected by lower muscle strength, agility, flexibility and cardiorespiratory fitness.A greater impairment of physical fitness in observed in children born very preterm (≤32 weeks of gestation).These findings might support the implementation of preventive strategies (e.g. fitness monitoring and exercise training) in preterm children since early childhood.

Impact of Motor Competence Profiles on Adolescents' Physical Activity and Cardiorespiratory Fitness across Four Years

INTRODUCTION

Physical activity levels have decreased over past decades with most adolescents neither meeting the current physical activity recommendations nor demonstrating adequate cardiorespiratory fitness (CRF). Motor competence (MC) is foundational for a physically active lifestyle; however, children demonstrate significant differences in their levels of MC in a broad foundation of movement skills. This study investigated developmental patterns of physical activity and CRF in children across 4 yr based on their longitudinal MC profiles.

METHODS

The data included annual measurements of MC, accelerometry-measured moderate-to-vigorous physical activity (MVPA), and CRF over 4 yr from the age 11 to 15 ( n = 1147, girls 582, boys 565). Latent profile analysis was used to identify longitudinal MC profiles and latent growth curve modeling to examine intercepts and slopes (s) of MVPA and CRF in these MC profiles.

RESULTS

Three different longitudinal MC profiles were identified: low, moderate, and high. The MC profiles showed significant differences in intercepts of CRF and MVPA. The high MC profile showed the highest intercepts for both, but also a statistically significant decline in MVPA over time (s = -3.36, P < 0.001). Cardiorespiratory fitness increased similarly in all three profiles over time: low (s = 1.20, P < 0.01), moderate (s = 1.28, P < 0.001), high (s = 2.21, P < 0.001).

CONCLUSIONS

These results highlight the long-term associations between different MC profiles and development of MVPA and CRF. Adolescents with lower MC demonstrated lower levels of MVPA and CRF, indicating decreased participation in physical activities that can optimally enhance CRF. However, significant differences in MVPA levels between MC profiles faded over time in adolescence, whereas significant differences in CRF remained.

Body Mass Index, Physical Activity, Cardiorespiratory Endurance and Quality of Life among Children with Physical Disabilities

BACKGROUND

Children with physical disabilities (PD) have reduced levels of physical activity (PA) compared to typically developing children, which increases their risk of becoming overweight and obese, which leads to numerous adverse health consequences. This study aimed to determine the differences between groups classified by body mass index (BMI) percentile in terms of PA levels, cardiorespiratory endurance and quality of life (QoL), and also to evaluate the relationship between BMI percentile and PA levels, cardiorespiratory endurance and QoL in children and adolescents with physical disabilities.

METHODS

A total of 172 children and adolescents with PD aged between 5 and 17 years from Hospital Tunku Azizah were included in this cross-sectional study. The BMI percentile was calculated to determine the weight status. PA levels were assessed with the Physical Activity Questionnaire for Older Children (PAQ-C), cardiorespiratory endurance was measured by the Six-Minute Walk Test (6MWT) and QoL was measured by the Paediatric Quality of Life Inventory version 2.0 (PedsQL 2.0).

RESULTS

According to the BMI percentile, 70.3% had a healthy BMI percentile (50th to 84th percentile), 11.6% were overweight (50th to 84th percentile), 11% were underweight (0-49th percentile) and 7.0% were obese (95th percentile and above). Most children reported a healthy weight, and the rates of being overweight and obese were higher in children who could ambulate without aids (6.4% and 3.5%, respectively) compared to those who used walking aids (5.2% and 3.5%, respectively). Significant differences were found in the PAQ-C, 6MWT and PedsQL 2.0 scores between different BMI percentile groups (p < 0.05). There were also significant correlations between the BMI percentile and the PAQ-C (r = 0.209, p < 0.001), 6MWT (r = 0.217, p < 0.001) and PedsQL 2.0 (r = 0.189, p < 0.001).

CONCLUSION

The rate of being overweight and obese is greater among children who ambulate without aids than among those with aids. An increase in the BMI percentile can reduce the QoL in different ways. This study suggests that children with PD who can walk without aids are at a greater risk of being overweight and obese. Hence, the engagement of this population in PA is crucial for their weight management.

Cardiorespiratory fitness and development of childhood cardiovascular risk: The EXAMIN YOUTH follow-up study

Background: Obesity- and hypertension-related cardiovascular (CV) risk has been shown to originate in childhood. Higher body mass index (BMI) and blood pressure (BP) have been associated with increased large artery stiffness and a lower microvascular arteriolar-to-venular diameter ratio (AVR) in children. This study aimed to investigate the association of cardiorespiratory fitness (CRF) with development of BMI, BP and vascular health during childhood. Methods: In our prospective cohort study, 1,171 children aged 6-8 years were screened for CRF, BMI, BP, retinal vessel diameters and pulse wave velocity using standardized protocols. Endurance capacity was assessed by 20 m shuttle run test. After 4 years, all parameters were assessed in 664 children using the same protocols. Results: Children with a higher CRF at baseline developed a significantly lower BMI (β [95% CI] -0.09 [-0.11 to -0.06] kg/m2, p < 0.001), a lower systolic BP (β [95% CI] -0.09 [-0.15 to -0.03] mmHg, p = 0.004) and a higher AVR (β [95% CI] 0.0004 [0.00004 to 0.0007] units, p = 0.027) after 4 years. The indirect association of CRF with development of retinal arteriolar diameters was mediated by changes in BMI. Conclusion: Our results identify CRF as a key modulator for the risk trajectories of BMI, BP and microvascular health in children. Obesity-related CV risk has been shown to track into adulthood, and achieving higher CRF levels in children may help counteract the development of CV risk and disease not only in pediatric populations, but may also help reduce the burden of CVD in adulthood. Registration: http://www.clinicaltrials.gov/ (NCT02853747).

Covid Pandemic Effects on the Physical Fitness of Primary School Children: Results of the German EMOTIKON Project

BACKGROUND

In spring of 2020, the Sars-CoV-2 incidence rate increased rapidly in Germany and around the world. Throughout the next 2 years, schools were temporarily closed and social distancing measures were put in place to slow the spread of the Covid-19 virus. Did these social restrictions and temporary school lockdowns affect children's physical fitness? The EMOTIKON project annually tests the physical fitness of all third-graders in the Federal State of Brandenburg, Germany. The tests assess cardiorespiratory endurance (6-min-run test), coordination (star-run test), speed (20-m sprint test), lower (powerLOW, standing long jump test), and upper (powerUP, ball-push test) limbs muscle power, and static balance (one-legged stance test with eyes closed). A total of 125,893 children were tested in the falls from 2016 to 2022. Primary analyses focused on 98,510 keyage third-graders (i.e., school enrollment according to the legal key date, aged 8 to 9 years) from 515 schools. Secondary analyses included 27,383 older-than-keyage third-graders (i.e., OTK, delayed school enrollment or repetition of a grade, aged 9 to 10 years), who have been shown to exhibit lower physical fitness than expected for their age. Linear mixed models fitted pre-pandemic quadratic secular trends, and took into account differences between children and schools.

RESULTS

Third-graders exhibited lower cardiorespiratory endurance, coordination, speed and powerUP in the Covid pandemic cohorts (2020-2022) compared to the pre-pandemic cohorts (2016-2019). Children's powerLOW and static balance were higher in the pandemic cohorts compared to the pre-pandemic cohorts. From 2020 to 2021, coordination, powerLOW and powerUP further declined. Evidence for some post-pandemic physical fitness catch-up was restricted to powerUP. Cohen's |ds| for comparisons of the pandemic cohorts 2020-2022 with pre-pandemic cohorts 2016-2019 ranged from 0.02 for powerLOW to 0.15 for coordination. Within the pandemic cohorts, keyage children exhibited developmental losses ranging from approximately 1 month for speed to 5 months for cardiorespiratory endurance. For powerLOW and static balance, the positive pandemic effects translate to developmental gains of 1 and 7 months, respectively. Pre-pandemic secular trends may account for some of the observed differences between pandemic and pre-pandemic cohorts, especially in powerLOW, powerUP and static balance. The pandemic further increased developmental delays of OTK children in cardiorespiratory endurance, powerUP and balance.

CONCLUSIONS

The Covid-19 pandemic was associated with declines in several physical fitness components in German third-graders. Pandemic effects are still visible in 2022. Health-related interventions should specifically target those physical fitness components that were negatively affected by the pandemic (cardiorespiratory endurance, coordination, speed).

Health Outcomes of Judo Training as an Organized Physical Activity for Children and Adolescents: A Literature Review

Judo, an organized physical activity for children and adolescents, has gained popularity worldwide. Physical activity is vital during times of rising obesity and a sedentary lifestyle in this age group. The article aims to review the current knowledge of the health benefits of judo-specific exercises for children and youth. Six international scientific databases (PubMed, Scopus, UpToDate, Web of Science, EBSCOhost, and Google Scholar) were searched from 1 January 2007 to 30 September 2022. The search focused on health-related factors regarding healthy preschool and school-aged judo practitioners. Sixteen original studies met the inclusion criteria. School-aged children aged 7-15 years were included in the analysis. The average training time was between two and six hours a week, with the judo intervention mainly ranging from nine months to three years. Most studies registered positive changes caused by judo training. The outcomes focused on maintaining or reducing body fat, increasing bone mineralization, and improving the function of the cardiorespiratory system compared to the non-practicing control group. However, there were no differences between judo and other sports groups. The main conclusions presented health benefits from judo-specific training in school-aged children and may support the World Health Organization recommendations concerning daily physical activity.

Cardiovascular fitness is associated with child adiposity at 5 years of age: findings from the ROLO longitudinal birth cohort study

BACKGROUND

Cardiovascular fitness is strongly linked with metabolic risk; however, research is limited in preschool children. Although there is currently no simple validated measure of fitness in preschool children, heart rate recovery has been highlighted as an easily accessible and non-invasive predictor of cardiovascular risk in school-aged children and adolescents. We aimed to investigate whether heart rate recovery was associated with adiposity and blood pressure in 5-year-olds.

STUDY DESIGN

This is a secondary analysis of 272 5-year-olds from the ROLO (Randomised cOntrol trial of LOw glycaemic index diet in pregnancy to prevent recurrence of macrosomia) Kids study. Three-minute step tests were completed by 272 participants to determine heart rate recovery duration. Body mass index (BMI), circumferences, skinfold thickness, heart rate, and blood pressure were collected. Independent t-tests, Mann-Whitney U, and Chi-square tests were used to compare participants. Linear regression models examined associations between heart rate recovery and child adiposity. Confounders included child sex, age at study visit, breastfeeding, and perceived effort in the step test.

RESULTS

The median (IQR) age at the study visit was 5.13 (0.16) years. 16.2% (n = 44) had overweight and 4.4% (n = 12) had obesity based on their BMI centile. Boys had a quicker mean (SD) heart rate recovery after the step test than girls (112.5 (47.7) seconds vs. 128.8 (62.5) seconds, p = 0.02). Participants with a slower recovery time (> 105 s) had higher median (IQR) sum of skinfolds (35.5 (11.8) mm vs. 34.0 (10.0) mm, p = 0.02) and median (IQR) sum of subscapular and triceps skinfold (15.6 (4.4) mm vs. 14.4 (4.0) mm, p = 0.02) compared to participants with a quicker recovery time. After adjusting for confounders (child sex, age at study visit, breastfeeding, effort in the step test), linear regression analyses revealed heart rate recovery time after stepping was positively associated with sum of skinfolds (B = 0.034, 95% CI: 0.01, 0.06, p = 0.007).

CONCLUSION

Child adiposity was positively associated with heart rate recovery time after the step test. A simple stepping test could be used as a non-invasive and inexpensive fitness tool in 5-year-olds. Additional research is needed to validate the ROLO Kids step test in preschool children.

Sex-Specific Differences in Left Ventricular Mass and Volumes with Body Mass Index among Children Aged 6 to 8: A Cross-Sectional Study in China

Few studies have examined the sex differences in left ventricle (LV) structure and physiology from early life stages. We aimed to assess the role of sex and overweight/obesity on left ventricular mass (LVM) and LV volume in Chinese children without preexisting cardiovascular risk factors. We selected 934 healthy children aged 6-8 years from an existing cohort in Beijing, China. Linear regression models were used to regress body mass index (BMI), fat mass, systolic blood pressure, diastolic blood pressure, waist circumference, and visceral fat area (VFA) with LVM, left ventricle end-diastolic volume (LVEDV) and end-systolic volume (LVESV). Higher BMI, fat mass, waist circumference, VFA, and stroke volume (SV) predicted higher LVM, LVEDV, and LVESV in both sexes. Multivariable analysis showed that boys with an elevated BMI had greater LV hypertrophy. LVEDV and LVESV were higher among boys than among girls and increased with higher BMI in both boys and girls. LVEDV and LVESV were associated with VFA in boys. We observed sex differences in LVM, LVESV, and LVEDV among prepubertal children, independent of obesity, with higher values observed in boys. Sex differences in cardiac structure in children may help explain the higher incidence of cardiovascular disease in male adults. Whether interventions to reduce childhood obesity can improve the trajectory of cardiac dynamics is worth investigating.

The stability of cardiometabolic risk factors clustering in children and adolescents: a 2-year longitudinal study

Objective

The present study aims to verify the odds of remaining with the clustering of 3 or more, 4 or more, and 5 or more risk factors across a 2-year time span.

Methods

Observational longitudinal study that included 358 children and adolescents (10.96 ± 2.28 years of age at baseline). Cardiorespiratory fitness, glucose, systolic blood pressure, total cholesterol/high-density lipoprotein cholesterol ratio, triglycerides, and waist circumference were assessed. The number of children in whom the risk factors were not independently distributed was analyzed. Odds ratios of presenting n risk factors clustered at follow-up according to the number of risk factors observed at baseline were calculated.

Results

More participants than expected were found presenting clustering of 4 or more and 5 or more risk factors at both baseline (11.7% and 5.6%, respectively) and follow-up (9.5% and 5.6%, respectively). The odds ratios calculated demonstrated that the odds of presenting the same number of risk factors clustered or more at follow-up increased according to the number of risk factors clustered at baseline.

Conclusion

The higher the number of risk factors a child had at baseline, the higher the odds of presenting the same number of risk factors or more after two years of follow-up.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01174-1.

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).

School-Based TGfU Volleyball Intervention Improves Physical Fitness and Body Composition in Primary School Students: A Cluster-Randomized Trial

This study aimed to explore whether a 16-week Teaching Games for Understanding (TGfU) volleyball intervention could improve primary school students' physical fitness and body composition. Eighty-eight primary school students (age 13.3 ± 0.3 years) were randomized to a TGfU volleyball intervention group (VG) or a control group (CG). The CG attended three regular physical education (PE) classes per week, while the VG attended two regular PE classes and a TGfU volleyball intervention that was implemented in the third PE class. Body composition components (body weight, body mass index, skinfold thickness, body fat percentage, and muscle mass percentage) and physical fitness (flexibility, vertical jumps (squat and countermovement jump-SJ/CMJ), 30 m sprint, agility, and cardiorespiratory fitness) assessments were performed pre-and post-intervention period. Significant interaction effects between VG and CG and pre- and post-test were found for the sum of five skinfolds (p < 0.0005, ŋp² = 0.168), body fat % (p < 0.0005, ŋp² = 0.200), muscle mass % (p < 0.0005, ŋp² = 0.247), SJ (p = 0.002, ŋp² = 0.103), CMJ (p = 0.001, ŋp² = 0.120), 30 m sprint (p = 0.019, ŋp² = 0.062), agility T-test (p < 0.0005, ŋp² = 0.238), and VO_2max (p < 0.0005, ŋp² = 0.253). Further examination revealed a greater improvement among VG students compared to CG students in certain body composition and physical fitness outcomes. Implementing a TGfU volleyball intervention in the physical education curriculum appears to have effective stimuli for reducing adiposity and promoting physical fitness levels in seventh-grade primary school students.

Secular Trends in Physical Fitness of Peruvian Children Living at High-Altitude

The physical fitness of children is an important marker of health, and monitoring its temporal changes provides important information for developing interventions. We aimed to: (1) describe secular trends in physical fitness across age, within each sex, in Peruvian schoolchildren; and (2) verify if these trends are also present when adjusted for changes in height and weight. We sampled 1590 children (707 in 2009; 883 in 2019), aged 6-11 years. Physical fitness was assessed with four tests from the EUROFIT battery. ANOVA and ANCOVA statistical models were used. Results showed that with increasing age, girls and boys were significantly stronger in all PF tests, except for the case of flexibility in girls. In 2019, girls were stronger (handgrip) and more flexible than in 2009; but lower values were evident in standing long jumps in both sexes. Age-by-year interactions were statistically significant for agility in both sexes, with significant differences occurring at different ages. These trends did not change when adjusted for temporal changes in height and weight. Our research provides important data for local governments to implement public policies and practices to improve physical fitness levels in children.

Individual and combined impact of physical fitness on health-related quality of life during adolescence: DADOS Study

The purpose of the present study was to investigate the individual and combined impact of physical fitness components at baseline on health-related quality of life (HRQoL) at 24-month follow-up in adolescents. This longitudinal research included 199 adolescents (13.9±0.3 years at baseline) from the DADOS study. Cardiorespiratory fitness was assessed using the 20-m shuttle run test. Muscular strength was assessed using the standing broad jump test. Motor competence was assessed using the 4 × 10-m shuttle run test. A physical fitness z-score was calculated as the mean of the z-scores values of each fitness test. A fitness index ranging from 0 to 3 was created according to the number of physical fitness components in which participants achieved high levels according to normative values. HRQoL was evaluated by the KIDSCREEN-10 questionnaire. Linear regression analyses showed that cardiorespiratory fitness, muscular strength, and the physical fitness z-score at baseline were individually associated with HRQoL at follow-up (β ranging from 0.123 to 0.183; all p < 0.05). Moreover, logistic regression analysis revealed that adolescents with a fitness index ≥1 at baseline were more likely to achieve high HRQoL at 24-month follow-up, compared with their peers with an index of 0 (OR ranging from 3.554 to 9.087; all p < 0.05). Our results revealed an individual and cumulative positive impact of physical fitness at baseline on HRQoL at 24-month follow-up. These findings underline the key role of promoting the enhancement of overall physical fitness components in order to improve adolescents' health and well-being.Highlights Adolescents with high levels of cardiorespiratory fitness, muscular strength and motor competence will benefit from a greater physical and mental well-being over the time.The more physical fitness components with optimal levels, the greater likelihood of reaching better HRQoL over the time.Public health authorities should focus on the promotion of multiple physical fitness components to increase adolescent's likelihood of achieving greater HRQoL over the time.

Cardiorespiratory fitness, body mass index, cardiovascular disease, and mortality in young men: A cohort study

Objective

We examined the association between cardiorespiratory fitness (CRF), body mass index (BMI), incidence of major acute cardiovascular events (MACE), and all-cause mortality (ACM).

Methods

We conducted a retrospective cohort study involving 212,631 healthy young men aged 16 to 25 years who had undergone medical examination and fitness testing (2.4 km run) from 1995 to 2015. Information on the outcomes of major acute cardiovascular events (MACE) and all-cause mortality (ACM) were obtained from the national registry data.

Results

During 2,043,278 person-years of follow-up, 371 first MACE and 243 ACM events were recorded. Compared against the first run-time quintile, adjusted hazard ratios (HR) for MACE in the second to fifth quintiles were 1.26 (95% CI 0.84-1.91), 1.60 (95% CI 1.09-2.35), 1.60 (95% CI 1.10-2.33), and 1.58 (95% CI 1.09-2.30). Compared against the "acceptable risk" BMI category, the adjusted HRs for MACE in the "underweight," "increased risk," and "high-risk" categories were 0.97 (95% CI 0.69-1.37), 1.71 (95% CI 1.33-2.21), and 3.51 (95% CI 2.61-4.72), respectively. The adjusted HRs for ACM were increased in participants from the fifth run-time quintile in the "underweight" and "high-risk" BMI categories. The combined associations of CRF and BMI with MACE showed elevated hazard in the "BMI≥23-fit" category, which was more pronounced in the "BMI≥23-unfit" category. The hazards for ACM were elevated across the "BMI<23-unfit," "BMI≥23-fit," and "BMI≥23-unfit" categories.

Conclusion

Lower CRF and elevated BMI were associated with increased hazards of MACE and ACM. A higher CRF did not fully compensate for elevated BMI in the combined models. CRF and BMI remain important targets for public health intervention in young men.

Normative values of cardiorespiratory fitness in Croatian children and adolescents

Although defining normative values of cardiorespiratory fitness have been the topic of many Western societies, little evidence has been provided for less developed countries like Croatia. Since cardiorespiratory fitness rapidly declines in Croatian children and adolescents, the newly established normative values would help health-related professionals and physical education teachers to detect 'talented' groups and direct them towards sport and 'risky' groups for planning special interventions. Therefore, the main purpose of the study was to determine normative reference values of cardiorespiratory fitness. A total of 1,612 children and adolescents aged 7-14 years (mean±SD; age 9.7±2.4 years; stature 151.0±17.6 cm; body mass 45.1±19.1 kg; 52.5% girls) participated in this cross-sectional study. Cardiorespiratory fitness was assessed by the Maximal multistage 20-m shuttle run test and the performance was expressed as the number of stages. Maximal oxygen uptake (VO2max) was estimated by equations. Smoothed percentile curves were calculated. Boys outperformed girls in the maximal number of levels achieved after the 20-m shuttle run test and in the VO2max values at each age category. In boys, a gradually higher level of performance between ages 11 and 14 was observed, while in girls the values started to rise after the age of 8. Our study provides one of the first sex- and age-specific normative values for cardiorespiratory fitness assessed by the 20-m shuttle run test in Croatian children and adolescents.

EFFECTS OF A SMALL-SIDED SOCCER PROGRAM ON HEALTH PARAMETERS IN OBESE CHILDREN

ABSTRACT Introduction: Childhood obesity is increasing and, as a consequence, it generates health complications resulting from sedentary behavior and low levels of physical fitness. There are few studies involving children, metabolic and cardiorespiratory profiles, and soccer. Objective: The purpose was to measure the effects of a 12-week recreational small-sided soccer program on cardiometabolic risk and individual responses to cardiometabolic risk factors in overweight or obese boys. Methods: Thirteen boys aged 8-12 years (34.9±11.6% body fat) participated in a 12-week recreational small-sided soccer training program with two 80-minute sessions per week at intensities over 80% of the maximal heart rate. Anthropometric characteristics, cardiorespiratory fitness, metabolic profile, individual responses to peak oxygen uptake (VO2peak), maximal workload (Wmax), fasting blood glucose, insulin, HOMA-IR, LDL-C, HDL-C, TC, and TG were measured both pre- and post-training. Results: Considering the individual responses of the participants, recreational soccer training was effective in improving variations in maximum power and exhaustion time, as well as promoting at least one beneficial change in cardiometabolic risk factors in 84% of the overweight or obese children. There were no differences between pre- and post-program anthropometric characteristics, metabolic profiles, or VO2peak values. Conclusion: Twelve-week recreational small-sided soccer programs were able to improve maximal power and anaerobic capacity and maintain cardiometabolic risk factor levels in overweight and obese boys. Level of evidence I; High-quality prospective study (all patients were enrolled at the same stage of disease, with >80% of patients enrolled) .

Effectiveness of an adapted physical activity intervention on health-related physical fitness in adolescents with intellectual disability: a randomized controlled trial

This study aimed to examine the effects of an adapted physical activity (APA) intervention on health-related physical fitness (HRPF) in adolescents with intellectual disability (ID). With a randomized controlled trial design, adolescents aged 12-18 years, with mild and moderate ID, and being overweight and obese were recruited and randomly assigned to either an intervention or a control group. The APA intervention consisted of overall moderate intensity aerobic and resistance exercise, with a duration of 45 min/session, a frequency of 2 sessions/week, and lasting for 9 months. A negative control was involved, in which participants received no treatment. Changes in four fitness tests, including the 9-min run/walk, handgrip strength, 30-s sit-ups, and sit-and-reach tests, were assessed between the groups using general linear models. A total of 57 participants (39 in the intervention group and 18 in the control group) completed the study. Significant mean differences in changes in the 9-min run/walk test (413.6 m [95% CI 146.72 m, 680.41 m], p = 0.003) and the right-side sit-and-reach test (2.2 cm [95% CI 0.37 cm, 4.09 cm], p = 0.020) respectively were observed in the intervention group, compared to the control group. No significant between-group improvement was observed for the handgrip strength and the 30-s sit-ups tests. The APA intervention induced beneficial effects on cardiorespiratory fitness and potential beneficial effects on flexibility for adolescents with ID. However, no significant effects of this intervention on muscular strength and endurance were observed in this study. Future studies should consider involving effective exercises in interventions to improve muscular strength and endurance.

Effect of adiposity and physical fitness on cardiometabolic risk factors in adolescents: A 2-year longitudinal study

Although risk factors for cardiometabolic diseases begin to present in young people, the association between physical fitness and adiposity with traditional and novel risk factors for cardiometabolic diseases across adolescence remains relatively unknown. Following ethical approval, fifty-two adolescents (age 11.6 ± 0.6 years; 32 girls) were recruited for a 2-years longitudinal study. Adiposity was assessed based on sum of skinfolds, waist circumference and body mass index, and physical fitness as distance run on the multi-stage fitness test (MSFT). Risk factors for cardiometabolic diseases (pro- and anti-inflammatory cytokines, plasma insulin, Homeostatic Model Assessment of Insulin Resistance - HOMA-IR, blood pressure) were measured following an overnight fast. Relationships between independent and response variables were analysed using multi-level modelling (final combined models were created using the stepwise backward elimination method). Plasma insulin concentration and HOMA-IR were positively associated with adiposity and inversely associated with distance run on the MSFT (all p < 0.05). The final combined models for plasma insulin concentration and HOMA-IR contained main effects for age, skinfolds and distance run on the MSFT. Levels of the anti-inflammatory cytokine IL-10 were inversely related to the sum of skinfolds (p = 0.046), whereas there was a trend for levels of the pro-inflammatory cytokine TNF-α to be positively related to the sum of skinfolds (p = 0.056). Adiposity and physical fitness are important, independent, determinants of metabolic health in adolescents. Furthermore, adiposity influences levels of pro- and anti-inflammatory cytokines in adolescence, with greater adiposity associated with a poorer inflammatory profile. The present study demonstrates an independent effect of physical fitness on metabolic health longitudinally across adolescence. It is therefore recommended that future work develops therapeutic interventions that reduce adiposity and enhance physical fitness in adolescents, to promote lifelong health.

Longitudinal Changes of Cardiorespiratory Fitness Performance in High School: Association with Individual and School-Based Variables

This study aimed to model adolescents' cardiorespiratory fitness performance change trajectories longitudinally across high school years and its relation to school- and individual/student-level factors. We employed hierarchical linear modeling to examine longitudinal cardiorespiratory fitness performance changes, as measured by the progressive aerobic capacity endurance run (PACER), over the years, between sexes, and in association with the school-level variables. Participants were 76,227 adolescents from 80 high schools in the mid-Atlantic region of the United States. School-level academic performance (SAP), the percent of students eligible for free and reduced-price meals (FARM), and physical education student-faculty ratio were obtained with permission from the school districts. The number of laps completed in PACER test improved throughout the first three years of high school, however, proportions of those within the healthy fitness zone (HFZ) decreased overall from 9th to 11th grade. Furthermore, the number of laps completed by adolescents appeared to have plateaued at 11th grade, with a significant decline during the final year of high school. Sex-based discrepancies in performance in meeting HFZ were evident, where girls significantly outperformed boys during 9th and 10th grades, and boys significantly outperformed girls during 12th grade. Additionally, SAP and FARM were positively and negatively, respectively, significantly associated with PACER performance at the school level. The odds ratio of adolescents performing in the HFZ declined significantly over the years, even though the number of PACER laps improved in the first three years. Concerted efforts should be targeted at improving cardiorespiratory fitness in high school due to its positive relationship to academic achievement in schools, and negative association with cardiovascular disease, metabolic syndrome, obesity, and all-cause mortality in adulthood.