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

Cardiorespiratory fitness, fatness, and the acute blood pressure response to exercise in adolescence

OBJECTIVE

Exaggerated exercise blood pressure (BP) is associated with cardiovascular risk factors in adolescence. Cardiorespiratory fitness and adiposity (fatness) are independent contributors to cardiovascular risk, but their interrelated associations with exercise BP are unknown. This study aimed to determine the relationships between fitness, fatness, and the acute BP response to exercise in a large birth cohort of adolescents.

METHODS

2292 adolescents from the Avon Longitudinal Study of Parents and Children (aged 17.8 ± 0.4 years, 38.5% male) completed a sub-maximal exercise step test that allowed fitness (VO2 max ) to be determined from workload and heart rate using a validated equation. Exercise BP was measured immediately on test cessation and fatness calculated as the ratio of total fat mass to total body mass measured by DXA.

RESULTS

Post-exercise systolic BP decreased stepwise with tertile of fitness (146 (18); 142 (17); 141 (16) mmHg) but increased with tertile of fatness (138 (15); 142 (16); 149 (18) mmHg). In separate models, fitness and fatness were associated with post-exercise systolic BP adjusted for sex, age, height, smoking, and socioeconomic status (standardized β: -1.80, 95%CI: -2.64, -0.95 mmHg/SD and 4.31, 95%CI: 3.49, 5.13 mmHg/SD). However, when fitness and fatness were included in the same model, only fatness remained associated with exercise BP (4.65, 95%CI: 3.69, 5.61 mmHg/SD).

CONCLUSION

Both fitness and fatness are associated with the acute BP response to exercise in adolescence. The fitness-exercise BP association was not independent of fatness, implying the cardiovascular protective effects of cardiorespiratory fitness may only be realized with more favorable body composition.

Differential Age-Related Declines in Cardiorespiratory Fitness Between People With and Without Type 2 Diabetes Mellitus

Objective

To assess the extent to which the established age-related decline in cardiorespiratory fitness (CRF) is augmented in adult men with type 2 diabetes mellitus (T2DM).

Participants and Methods

This study used data from the Aerobics Center Longitudinal Study, conducted between September 18, 1974, and August 3, 2006, in primarily non-Hispanic white, middle-to-upper class adults. The analyses were restricted to adult men with complete data on age, CRF, and T2DM (35,307 participants). Quantile regression models were used to estimate age-related differences in CRF, estimated using a maximal treadmill test, between persons with and without T2DM. Smoking status and birth cohort served as covariates.

Results

Age-related declines in CRF were observed in men with and without T2DM. For men younger than 60 years, at low-mid percentiles of the CRF distribution the magnitude of the age-related decline in CRF was significantly higher (P-values=.00, .02) in men with T2DM than in those without T2DM. At upper percentiles, the decline with age between the 2 groups was virtually identical. Significant declines in CRF in men 45 years or younger were observed only at high levels of CRF for those without T2DM and at low levels of CRF for those with T2DM (P-values .00, .04).

Conclusion

This study reported that men younger than 60 years with T2DM at the low-mid CRF percentiles experience an accelerated age-related decline in CRF. Men younger than 60 years with T2DM exhibiting high levels of CRF experienced a decline in CRF comparable to men without T2DM. This study highlights the importance of incorporating sufficient levels of exercise or activity to maintain high CRF in men with T2DM.

The epidemiology of muscle-strengthening activity among adolescents from 28 European countries

AIMS

This study aimed to describe the prevalence and socio-demographic and lifestyle-related correlates of muscle-strengthening activity (MSA; strength/resistance training, sit-ups/push-ups, etc.) among a large sample of European adolescents.

METHODS

Data were drawn from the European Health Interview Survey Wave 2 (2013-2014), including 8818 adolescents (15-17 years) from 28 European countries. Self-reported MSA was assessed using a previously validated survey item. Population-weighted prevalence ratios were calculated for (a) 'none' (0 days/week), (b) 'insufficient MSA' (1-2 days/week) or (c) 'sufficient MSA' (⩾3 days/week). Generalised linear models using Poisson regression with robust error variance were used to calculate the prevalence ratios for adolescents reporting sufficient MSA by socio-demographic/lifestyle characteristics and by European region.

RESULTS

Overall, 19.4% (95% confidence interval (CI) 18.3-20.7) reported sufficient (⩾3 days/week) MSA and 57.9% (95% CI 56.4-59.6) reported none. Females, adolescents from Southern and Eastern European regions, those not meeting the aerobic guideline and adolescents classified as overweight were significantly associated with a lower likelihood of reporting sufficient MSA, independent of other characteristics.

CONCLUSIONS

The majority of European adolescents do not meet the MSA guidelines. Future large-scale MSA public-health interventions should target female and currently inactive adolescents, as well as those from Southern and Eastern European regions.

Associations between physical activity motives and trends in moderate-to-Vigorous physical activity among adolescents over five years

This study examined the longitudinal associations between five physical activity (PA) motives and moderate-to-vigorous PA (MVPA) across a 5-year period spanning late childhood to middle adolescence.METHODS: Data (n = 937; 55% girls; mean age = 10.33 years) were drawn from the Monitoring Activities for Teenagers to Comprehend their Habits study. PA motives and MVPA were assessed 15 times over the course of 5 years. Measurement invariance for the Motives for Physical Activity Measure-Revised (MPAM-R) questionnaire was established, and sex-stratified mixed-effects regression models were analysed.MVPA increased until a mean age of 12.18 years for girls and 12.89 years for boys before decreasing through the final assessment. From late childhood to middle adolescence, for boys, enjoyment motives were positively (β(95% CI) = 6.14(3.86-8.43)), while fitness motives were negatively (β(95% CI) = -4.80(-8.0, -1.59)) associated with MVPA. Whereas, for girls, competence motives were positively β(95% CI) = 3.44(1.59-5.28)) associated with MVPABoys may benefit from PA interventions, if these were primarily aimed at increasing ones' enjoyment, whereas developing a girl's competence may provide greater contributions to a girl's future PA behaviours. PA interventions should avoid promoting the desire to be active to improve fitness, particularly among boys.

Identifying childhood movement profiles and comparing differences in mathematical skills between clusters: A latent profile analysis

The aims of this study were; 1) to identify different movement profiles in sixth graders, and 2) to investigate if there are differences in their mathematical basic (BasicMath) and problem solving (ProbSol) skills between existing movement profiles. The sample included 461 (223 girls, 238 boys) students with a mean age of 11.27 ± .32 years from southern and middle Finland. A latent profile analysis (LPA) revealed four movement profiles: "poor movers", "average movers", "skilled movers" and "expert movers". These profiles differed substantially in their motor competence (MC) and health-related fitness (HRF). A multivariate analysis of variance (MANOVA) also revealed that "poor movers" and "average movers" obtained lower results in BasicMath comparing with "skilled movers". The results of this study suggest that cardiorespiratory and muscular fitness, MC and BasicMath are interrelated.

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 ± standard deviation) 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 behavior (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.

Association between Health-Related Physical Fitness and Respiratory Diseases in Adolescents: An Age- and Gender-Matched Study

The current study examined the differences in health-related physical fitness (HRPF), physical activity (PA), and sedentary behavior (SB) between adolescents with and without ongoing respiratory diseases (RD). This study's participants were from 12 to 15 years old (7th-10th grade) in South Korea. Adolescents with RD were selected through RD-related questions (i.e., asthma, rhinitis, sinusitis, and bronchitis) (n = 139); in contrast, adolescents without RD, randomly selected from the general group, responded to any health problem-related questions as "No" (n = 139). HRPF was measured based on the FITNESSGRAM and EURO FIT test batteries and the measurements of HRPF included cardiovascular endurance, muscular strength, muscular endurance, flexibility, and body composition. All statistical analyses were conducted by SPSS 25.0, and the independent t-test was used to compare the HRPF and PA between the two groups. Moreover, the measured HRPF was compared with a series of analyses of three-way ANOVAs (age × gender × group). Adolescents with RD had a positive association with less participation in PA (p < 0.05; RD: 3081.81 ± 4793.37; general: 2073.64 ± 3123.47) and with more time spent on SB (above 12 h per week: RD group (38.85%) and general group (33.09%)). Furthermore, adolescents in the RD group showed significant effects on all components of HRPF (p < 0.05). Our study confirmed that HRPF is an essential predictor of adolescents' health outcomes, especially for those with RD. We suggest that increased HRPF can be an effective treatment for respiratory diseases in adolescents, and health practitioners should pay more attention to helping adolescents with RD to gain or maintain high HRPF.

Association between physical fitness components and fluid intelligence according to body mass index in schoolchildren

Physical fitness is considered a protective factor for children's general health and has been related to enhanced cognitive functioning. However, it appears that cognition could be affected in children with overweight or obesity. The present study aimed to determine the relationship between physical fitness components and fluid intelligence in normal-weight and overweight/obese children. In this cross-sectional study, a total of 317 schoolchildren participated (165 boys, 52.05%), aged between six and 11 years old (1st to 5th grade), belonging to a public school in the south of Brazil. Psychologists evaluated fluid intelligence through the Raven's Colored Progressive Matrix Test. The physical fitness evaluation followed the procedures of the "Brazil Sports Project". Weight and height were measured to determine body mass index and generalized linear regression analyses were used with a 95% confidence interval. Our results showed that agility was inversely associated with fluid intelligence only in the overweight/obese group (β = -1.506; p = 0.01). Cardiorespiratory and muscular fitness were not associated with fluid intelligence. In conclusion, agility was the only physical fitness component related to fluid intelligence, and this relationship was found exclusively in overweight/obese schoolchildren.

Neck circumference and cardiometabolic risk in children and adolescents: the moderator role of cardiorespiratory fitness

BACKGROUND

The increased incidence of cardiometabolic risk factors has become a public health issue, especially in childhood and adolescence. Thus, early identification is essential to avoid or reduce future complications in adulthood. In this sense, the present study aimed to verify the influence of cardiorespiratory fitness (CRF) as a moderator in the association between neck circumference (NC) and cardiometabolic risk in children and adolescents.

METHODS

Cross-sectional study that included 2418 randomly selected children and adolescents (52.5% girls), aged 6 to 17 years old. Anthropometric measurements, such as NC and body mass index (BMI), and CRF was measured by the six-minute running/walking test, as well as cardiometabolic risk (systolic blood pressure, glucose, HDL-C, and triglycerides), were assessed.

RESULTS

For all age groups, NC showed a negative relationship with CRF. A significant interaction term was found for CRF x NC with cardiometabolic risk for children (6 to 9 years old), early adolescents (10 to 12 years old), and middle adolescents (13 to 17 years old). It was found that children who accomplished more than 1092.49 m in CRF test were protected against cardiometabolic risk when considering NC. In adolescents, protection against cardiometabolic risk was found when the CRF test was completed above 1424.14 m and 1471.87 m (early and middle stage, respectively).

CONCLUSIONS

CRF is inversely associated with NC and acts as a moderator in the relationship between NC and cardiometabolic risk in children and adolescents. Therefore, this detrimental health impact linked to fatness might be attenuated by improving CRF levels.

Cardio-Metabolic Risk Factors in Scottish South Asian and Caucasian Youth

(1) Background: Scotland has one of the highest rates of obesity in the Western World, it is well established that poor weight profiles, and particularly abdominal obesity, is strongly associated with Type II diabetes and cardiovascular diseases. Whether these associations are apparent in ethnic population groups in Scotland is unclear. The purpose of this study was to examine the associations between different measures of fatness with clustered cardio metabolic risk factors between Scottish South Asian adolescents and Scottish Caucasian adolescents; (2) Methods: A sample of 208 Caucasian adolescents and 52 South Asian adolescents participated in this study. Stature, waist circumference, body mass index, blood pressure, physical activity, and cardiovascular disease (CVD) risk were measured; (3) Results: Significant, partial correlations in the South Asian cohort between body mass index (BMI) and individual risk factors were generally moderate. However, correlations between Waist circumference (WC) and individual risk factors were significant and strong. In the Caucasian cohort, a significant yet weak correlation between WC and total cholesterol (TG) was noted although no other associations were evident for either WC or BMI. Multiple regression analysis revealed that both BMI and WC were positively associated with CCR (p < 0.01) in the South Asian group and with the additional adjustment of either WC or BMI, the independent associations with clustered cardio-metabolic risk (CCR) remained significant (p < 0.005); (4) Conclusions: No positive relationships were found between BMI, WC, and CCR in the Caucasian group. Strong and significant associations between measures of fatness and metabolic risk were evident in Scottish South Asian adolescents.

Traditional and New Perspectives on Youth Cardiorespiratory Fitness

PURPOSE

This study aimed to review traditional and new perspectives in the interpretation of the development of youth cardiorespiratory fitness (CRF).

METHODS

We analyzed data from (i) the literature which for 80 yr has been traditionally based on interpretations of peak oxygen uptake (V˙O2) in ratio with body mass (BM) and (ii) recent multilevel allometric models founded on 994 (475 from girls) determinations of 10- to 16-yr-olds' peak V˙O2 with measures of age, maturity status, and morphological covariates (BM and fat-free mass), and from 10 to 13 yr, 110 peak V˙O2 determinations of maximum cardiovascular covariates (stroke volume, cardiac output, and arteriovenous oxygen difference).

RESULTS

The application of ratio scaling of physiological variables requires satisfying specific statistical assumptions that are seldom met. In direct conflict with the ratio-scaled data interpretation of CRF, multilevel allometric modeling shows that with BM controlled, peak V˙O2 increases with age but the effect is smaller in girls than boys. Maturity status exerts a positive effect on peak V˙O2, in addition to those of age and BM. Changes in maximum cardiovascular covariates contribute to explaining the development of CRF, but fat-free mass (as a surrogate for active muscle mass) is the most powerful single influence. With age, maturity status, morphological covariates, and maximum cardiovascular covariates controlled, there remains an unexplained ~4% to ~9% sex difference in peak V˙O2.

CONCLUSIONS

The traditional interpretation of peak V˙O2 in ratio with BM is fallacious and leads to spurious correlations with other health-related variables. Studies of the development of CRF require analyses of sex-specific, concurrent changes in age- and maturation-driven morphological and maximum cardiovascular covariates. Multilevel allometric modeling provides a rigorous, flexible, and sensitive method of data analysis.

Reciprocal Longitudinal Relationship Between Fitness, Fatness, and Metabolic Syndrome in Brazilian Children and Adolescents: A 3-Year Longitudinal Study

PURPOSE

To verify the reciprocal longitudinal relationships between cardiorespiratory fitness (CRF), percentage body fat (%body fat), and metabolic syndrome in Brazilian primary school students.

METHOD

This longitudinal study involved 420 children and adolescents followed for 3 years (2011-2014). The continuous Metabolic Syndrome (cMetSyn) score was calculated by summing adjusted z scores of glucose, systolic blood pressure, total cholesterol/high-density lipoprotein cholesterol ratio, triglycerides, and waist circumference. The CRF was assessed using running/walking tests, and %body fat was assessed through sex-specific 2-site skinfold thickness. Cross-lagged panel models were used to analyze longitudinal reciprocal relationships between CRF and %body fat with cMetSyn.

RESULTS

Results indicated that 2011 %body fat significantly predicted both 2014 CRF scores and 2014 cMetSyn scores (P < .001); however, 2011 CRF only predicted 2014 %body fat (P < .001) but not 2014 cMetSyn (P = .103). Furthermore, 2011 cMetSyn predicted 2014 %body fat (P = .002). The model explained 36%, 48%, and 37% of the variance in 2014 CRF, %body fat, and cMetSyn, respectively.

CONCLUSION

The results suggest a reciprocal inverse relationship between %body fat and metabolic syndrome risk and that %body fat may play a more important role in the risk of developing metabolic syndrome compared with CRF.

Aerobic fitness and the sleeping brain of adolescents-a pilot study

STUDY OBJECTIVES

Aerobic fitness (AF) and sleep are major determinants of health in adolescents and impact neurocognitive and psychological development. However, little is known about the interactions between AF and sleep during the developmental transition experienced across adolescence. This study aimed to consider the relationships between AF and habitual sleep patterns and sleep neurophysiology in healthy adolescents.

METHODS

Subjects (mean age = 14.6 ± 2.3 years old, range 11-17, 11 females) were evaluated for AF (peak VO2 assessed by ramp-type progressive cycle ergometry in the laboratory), habitual sleep duration and efficiency (7-14 days actigraphy), and topographic patterns of spectral power in slow wave, theta, and sleep spindle frequencies in non-rapid eye movement (NREM) sleep using overnight polysomnography (PSG) with high-density electroencephalography (hdEEG, 128 channels).

RESULTS

Significant relationships were observed between peak VO2 and habitual bedtime (r = -0.650, p = .009) and wake-up time (r = -0.603, p = .017), with greater fitness associated with going to bed and waking up earlier. Peak VO2 significantly predicted slow oscillations (0.5-1 Hz, p = .018) and theta activity (4.5-7.5 Hz, p = .002) over anterior frontal and central derivations (p < .001 and p = .001, respectively) after adjusting for sex and pubertal development stage. Similar associations were detected for fast sleep spindle activity (13-16 Hz, p = .006), which was greater over temporo-parietal derivations.

CONCLUSIONS

Greater AF was associated with a more mature pattern of topographically-specific features of sleep EEG known to support neuroplasticity and cognitive processes and which are dependent on prefrontal cortex and hippocampal function in adolescents and adults. AF was also correlated with a smaller behavioral sleep phase delay commonly seen during adolescence.

The mediating role of adiposity in the longitudinal association between cardiorespiratory fitness and blood pressure in adolescents: LabMed cohort study

BACKGROUND

The aim of this prospective cohort study was to examine whether the association between the cardiorespiratory fitness (CRF) at baseline and blood pressure (BP) at follow-up is mediated by adiposity in adolescents.

MATERIALS AND METHODS

The sample comprised 734 adolescents (349 girls) aged 12-18 years from the LabMed Physical Activity Cohort Study. The variables of interest were measured in 2011 (baseline) and in 2013 (2-year follow-up). CRF was assessed by the 20-m shuttle run test. Body mass index, waist circumference, body fat percentage, pubertal status and resting BP were assessed according to standard procedures. Boot-strapped mediation procedures were performed, and indirect effects (IE) with confidence intervals (CI) not including zero were considered statistically significant.

RESULTS

After adjusting for potential confounders, body mass index acted as a mediator of the relationship between CRF and systolic BP (IE = -0. 023; CI = -0.039; -0.009), pulse pressure (IE = -0.023; CI = -0.034; -0.012) and rate product pressure (IE = -2.839; CI = -5.329; -0.340). Similar results were obtained for waist circumference as mediator for systolic BP (IE = -0.019; CI = -0.033; -0.005), pulse pressure (IE = -0.017; CI = -0.028; -0.007) and rate product pressure (IE = -3.793; CI = -6.097; -1.689). Likewise, body fat percentage mediated the association for: systolic BP (IE = -0.029; CI = -0.048; -0.010), pulse pressure (IE = -0.027; CI = -0.041; -0.013) and rate product pressure (IE = -4.280; CI = -7.488; -1.264).

CONCLUSIONS

Adiposity mediated the association between CRF and BP in adolescents. Therefore, both optimal CRF and adiposity levels are important to maintain normal BP ranges throughout adolescence.

Is physical fitness associated with the type of attended school? A cross-sectional analysis among 20.000 adolescents

BACKGROUND

While academic achievement has been associated with physical activity, the present work questions the potential association between the physical fitness level of adolescents and the type of school they attend, ranging from academic to technical schools.

METHODS

20,228 young French students from 76 schools (9,196 females), mean age 15.8±1.8 years, performed the Diagnoform© test. This dataset includes two higher education institutions (n=870), 37 general high schools (n=13,125), 18 professional-oriented high schools (n=3,569), 5 agricultural high schools (n=132), 2 vocational training centers (n=202) and 12 rural vocational training centers (n=1,137).

RESULTS

In higher education institutions and general high schools, girls showed better performances for all physical tests. A decreasing Quotient of overall Physical fitness Condition (QPC) was observed for both genders from urban higher education schools to rural and technical institutions (p<0.001). The proportion of total variance accounting for within institution variation is strong (intra-class correlation coefficients (ICC) 0.20 [0.15; 0.27] for QPC).

CONCLUSIONS

The lower physical fitness level observed here among students from technical or training schools places them at higher risks for the development of future chronic diseases. These results suggest that specific interventions are needed depending on the educational setting.

Tracking of cardiometabolic risk in a Brazilian schoolchildren cohort: a 3-year longitudinal study

BACKGROUND

Clustering of cardiometabolic risk factors is a sign of detrimental health. Tracking is a term used to describe a variable longitudinal stability across time. High tracking provides the chance to determine which cardiometabolic risk factors should be the target of early treatment and prevention efforts. The present study aims to analyze the tracking of cardiometabolic risk factors and clustered cardiometabolic risk score in children across a 3-year time span, and to verify the odds of staying at risk (measured by the clustered score) from baseline to follow-up.

METHODS

Longitudinal study that included 354 (155 boys) children, aged 7-12 years at baseline. A clustered score was calculated by summing the systolic blood pressure, waist circumference, triglycerides, glucose, and the TC/HDL-C ratio Z-scores divided by five. A second clustered score was calculated including cardiorespiratory fitness (CRF).

RESULTS

CRF and anthropometric parameters presented high tracking (r≥0.662), whereas the cardiometabolic parameters exhibited low-to-moderate tracking (0.100≤r≤0.571). The clustered scores' tracking was moderate (r≥0.508; r≥0.588 [CRF]). Participants in the higher risk groups at baseline presented 3.81 (95% CI: 2.40; 6.05) and 4.64 (95% CI: 2.85; 7.56), including CRF, times higher chance of remaining at risk three years later. Moreover, participants in the worst profile regarding CRF or anthropometrics at baseline presented at least 4.00 times higher chance of being at risk three years later.

CONCLUSIONS

Participants with worst CRF and adiposity had an increased risk of presenting higher clustered risk after three years.

Physical Fitness and Motor Competence in Upper Austrian Elementary School Children-Study Protocol and Preliminary Findings of a State-Wide Fitness Testing Program

Motor competence and physical fitness are key components for the promotion of an active and healthy lifestyle. Poor motor competence and low physical fitness in children, therefore, are a major threat to future public health. Even though the assessment of physical fitness and motor competence per se does not enhance these entities, fitness tests can provide important information for intervention strategies. Fitness tests may also motivate children to become more active in order to increase their physical abilities. In the school-year 2016/17 the Upper Austrian government initiated the state-wide testing program "wie fit bist du" (how fit are you) in elementary schools, that examined cardiorespiratory fitness, muscular power, speed, agility, flexibility and object control skills along with the assessment of height and weight. Since the beginning of the program more than 18,000 children between 6 and 11 years of age participated in the school-based tests. The results show a significant increase in the prevalence of overweight/obesity with increasing age (p > 0.01). Overweight/obese children displayed lower motor competence and physical fitness, except for upper body strength. Further, the improvement in test performance with increasing age was less pronounced in overweight/obese children compared to their normal weight peers. In fact, distance covered during the 6-min run did not improve throughout the elementary school years in overweight/obese children. Given the importance of motor competence and physical fitness for general development and well-being, physical education should be considered a viable setting for the promotion of these entities as a majority of children can be reached independent of their socio-economic background. In order to provide adequate movement experiences that enhance motor competence and physical fitness while ensuring a motivating environment, objective information on current ability levels are required. The implementation of fitness monitoring at young ages, therefore, can be an important contributor for the promotion of an active and healthy lifestyle.

Cardiorespiratory Fitness Predicted by Fibrinogen and Leptin Concentrations in Children with Obesity and Risk for Diabetes: A Cross-Sectional Study and a ROC Curve Analysis

Obesity is defined as abnormal or excessive fat accumulation that presents a risk to health. The ability to exercise is affected by adiposity, and this mechanism involves low-grade chronic inflammation and homeostatic stress produced mainly in adipocytes, which can result in abnormal adipokine secretion. To date, the gold standard for cardiorespiratory fitness assessment is considered to be the maximum oxygen uptake (VO_2max). The aim of the present study was to assess the prognostic value of hematological parameters of childhood obesity, as potential predictors of cardiorespiratory fitness (VO_2max), using a sample of children and adolescents with obesity and risk for diabetes. A total of 84 clinically healthy children and adolescents were recruited, of which 21 were considered lean, 22 overweight and 41 obese, with a mean age of 12.0 ± 1.9, 11.4 ± 2.0, and 11.2 ± 2.1 years old, in each weight status category, respectively. Age and sex did not differ between groups. Hematologic testing was performed after 12 h of fasting including glucose, serum lipids, insulin, hc-CRP, adiponectin, leptin and fibrinogen levels. Cardiorespiratory capacity for exercise was assessed to determine VO_2max, using a cycle ergometer. The VO_2max was negatively correlated with progressive strength to the BMIz (-0.656, p ≤ 0.001), hs-CRP (r = -0.341, p ≤ 0.002), glucose (r = -0.404, p ≤ 0.001) and insulin levels (r = -0.348, p ≤ 0.001), the homeostasis model assessment of insulin resistance (HOMA-IR) (r = -0.345, p ≤ 0.002), as well as to the leptin (r = -0.639, p ≤ 0.001) and fibrinogen concentrations (r = -0.520, p ≤ 0.001). The multivariate analysis revealed that only leptin and fibrinogen concentrations could predict the VO_2max adjusted for the BMIz of participants. The receiver operating characteristic (ROC) curve for the diagnostic accuracy of leptin, hs-CRP and fibrinogen concentrations for the prediction of VO_2max revealed a good diagnostic ability for all parameters, with leptin being the most promising one (area under the curve (AUC): 99%). The results verify that in children with obesity, VO_2max may be predicted from hematological parameters (leptin and fibrinogen), possibly bypassing more invasive methods.

Fitness, waist circumference and their association with future blood pressure in youth: The UP&DOWN Longitudinal Study

OBJECTIVES

The aim was to determine the independent associations of muscular fitness (MF), cardiorespiratory fitness (CRF) and waist circumference (WC) with blood pressure (BP) levels over 2 years in children and adolescents.

METHODS

1089 children (517 females) and 787 adolescents (378 females) with complete data on fitness, WC and BP (systolic [SBP] and diastolic [DBP]) were included. Upper MF was assessed through the handgrip strength test, and lower MF using the standing long jump test. The 20-m shuttle run test was used to assess CRF. WC was obtained following standardized methods. Different regression models were fitted by introducing fitness and WC at baseline and their changes as exposures and BP at follow-up and their changes as outcomes.

RESULTS

WC at baseline was positively and independently associated with each BP variable at follow-up in children and adolescents (β=0.094-0.260; p≤0.05), and CRF was negatively associated with DBP in adolescents (β=-0.096; p=0.034). WC changes were associated with BP variables 2 years later in children (β=0.121-0.142; p<0.01). In adolescents, changes in upper MF (β=-0.116; p=0.001) and WC (β=0.080-0.098; p<0.05) were associated with SBP at follow-up. WC changes were independently associated with changes in each BP variable in children (β=0.111-0.145; all p<0.05) and SBP changes in adolescents (β=0.103 to 0.117; all p<0.01).

CONCLUSIONS

WC, but neither MF nor CRF, is independently associated with BP and its changes over 2 years. The attainment or maintenance of optimal fatness levels in the pediatric population should be highly encouraged for the prevention of future hypertension.

An Update on Secular Trends in Physical Fitness of Children and Adolescents from 1972 to 2015: A Systematic Review

BACKGROUND

There is evidence that physical fitness of children and adolescents (particularly cardiorespiratory endurance) has declined globally over the past decades. Ever since the first reports on negative trends in physical fitness, efforts have been undertaken by for instance the World Health Organization (WHO) to promote physical activity and fitness in children and adolescents. Therefore, it is timely to re-analyze the literature to examine whether previous reports on secular declines in physical fitness are still detectable or whether they need to be updated.

OBJECTIVES

The objective of this systematic review is to provide an 'update' on secular trends in selected components of physical fitness (i.e., cardiorespiratory endurance, relative muscle strength, proxies of muscle power, speed) in children and adolescents aged 6-18 years.

DATA SOURCES

A systematic computerized literature search was conducted in the electronic databases PubMed and Web of Science to locate studies that explicitly reported secular trends in physical fitness of children and adolescents.

STUDY ELIGIBILITY CRITERIA

Studies were included in this systematic review if they examined secular trends between at least two time points across a minimum of 5 years. In addition, they had to document secular trends in any measure of cardiorespiratory endurance, relative muscle strength, proxies of muscle power or speed in apparently healthy children and adolescents aged 6-18 years.

STUDY APPRAISAL AND SYNTHESIS METHODS

The included studies were coded for the following criteria: nation, physical fitness component (cardiorespiratory endurance, relative muscle strength, proxies of muscle power, speed), chronological age, sex (boys vs. girls), and year of assessment. Scores were standardized (i.e., converted to z scores) with sample-weighted means and standard deviations, pooled across sex and year of assessment within cells defined by study, test, and children's age.

RESULTS

The original search identified 524 hits. In the end, 22 studies met the inclusion criteria for review. The observation period was between 1972 and 2015. Fifteen of the 22 studies used tests for cardiorespiratory endurance, eight for relative muscle strength, eleven for proxies of muscle power, and eight for speed. Measures of cardiorespiratory endurance exhibited a large initial increase and an equally large subsequent decrease, but the decrease appears to have reached a floor for all children between 2010 and 2015. Measures of relative muscle strength showed a general trend towards a small increase. Measures of proxies of muscle power indicated an overall small negative quadratic trend. For measures of speed, a small-to-medium increase was observed in recent years.

LIMITATIONS

Biological maturity was not considered in the analysis because biological maturity was not reported in most included studies.

CONCLUSIONS

Negative secular trends were particularly found for cardiorespiratory endurance between 1986 and 2010-12, irrespective of sex. Relative muscle strength and speed showed small increases while proxies of muscle power declined. Although the negative trend in cardiorespiratory endurance appears to have reached a floor in recent years, because of its association with markers of health, we recommend further initiatives in PA and fitness promotion for children and adolescents. More specifically, public health efforts should focus on exercise that increases cardiorespiratory endurance to prevent adverse health effects (i.e., overweight and obesity) and muscle strength to lay a foundation for motor skill learning.

Formative Evaluation of a Home-Based Physical Activity Intervention for Adolescent Girls-The HERizon Project: A Randomised Controlled Trial

BACKGROUND

This is a formative evaluation study of the HERizon Project, a home-based multi-component physical activity (PA) intervention for adolescent girls in the UK and Ireland. Although not intended, this study coincided with the initial COVID-19 lockdown restrictions.

METHODS

A total of 42 female participants, aged 13 to 16 years old (mean = 14.2, SD = 1.1), were randomly allocated to: (i) the HERizon group (n = 22) or (ii) the wait-list control group (n = 20). Participants in the six-week HERizon group were asked to complete three PA sessions each week and engage in weekly behaviour change support video calls. The primary outcome measure was self-reported habitual PA. Secondary outcomes measures included cardiorespiratory fitness (20 m shuttle run), muscular strength (standing long jump), muscular endurance (push up test), and psychosocial outcomes (Perceived Competence Scale, Body Appreciation Scale, Self-Esteem Questionnaire, Behavioural Regulation in Exercise Questionnaire). Quantitative and qualitative process evaluation data were also collected. Outcome measures were assessed at baseline and after the six-week intervention.

RESULTS

There was no significant change in habitual PA between groups (LMM group*time interaction: p = 0.767). The HERizon group had significantly increased cardiorespiratory fitness (p = 0.001), muscular endurance (p = 0.022), intrinsic motivation (p = 0.037), and body appreciation (p < 0.003) in comparison to the wait-list control group. All participants in the intervention group completed the intervention and compliance to the intervention was high (participants completed 18 ± 2 sessions).

CONCLUSIONS

Although no change in PA was observed, HERizon resulted in improved physical fitness and psychosocial outcomes. These preliminary findings, alongside positive findings for feasibility and acceptability, highlight potential benefits from the home-based intervention, thus further investigation is warranted.

Seasonal variability of the vitamin D effect on physical fitness in adolescents

Studies investigating the relationship between vitamin D and physical fitness in youth have provided inconsistent findings. Recent evidence indicates that the expression of receptors and vitamin D-modulated genes in young subjects has a seasonal profile. Therefore, we investigated the role of vitamin D on physical fitness across seasons in a total of 977 male adolescents. Anthropometrics, lifestyle, dietary habits, biochemical profiles and physical fitness were studied. Multiple linear regression models, including pairwise interaction terms involving total 25-OH-vitamin D, were fitted. The interacting effect of season and total 25-OH-vitamin D had a significant influence on physical fitness performance (spring and total 25-OH-vitamin D: ß 0.19, SE 0.07, p = 0.007; summer and total 25-OH-vitamin D: ß 0.10, SE 0.06, p = 0.11; autumn and total 25-OH-vitamin D: ß 0.18, SE 0.07, p = 0.01), whereas the main effect of total 25-OH-vitamin D alone was not significant (p = 0.30). Body fat percentage, recreational physical activity level, time spent per day gaming/TV-watching, smoking, and hemoglobin levels were also related to the physical fitness performance score. Future studies should further explore the role of seasonal-dependent effects of vitamin D on health.

Letter to the Editor on: "Effectiveness of Multi-activity, High-intensity Interval Training in School-aged Children."

Recently, Ketelhut et al. published an article on the effectiveness of a multi-activity high-intensity interval training in school-aged children on aerobic fitness and hemodynamic parameters in the International Journal of Sports Medicine. With this letter to the editor we would like to comment on the methods and clinical relevance of the results found.

Clustering of 24-h movement behaviors associated with cardiorespiratory fitness among adolescents: a latent class analysis

This study aimed to examine the clustering of 24-h movement behaviors (moderate to vigorous physical activity, screen time, and sleep duration) and their association with cardiorespiratory fitness among adolescents. We evaluated 561 adolescents (52.1% girls; mean age, 13.0 ± 1.0 years) from Florianópolis, Brazil. A 20-m shuttle run was used to assess cardiorespiratory fitness, while a questionnaire was used to measure 24-h movement behaviors. A latent class analysis was performed to identify the clustering of 24-h movement behaviors, while linear Bayesian mixed-effect regression models were applied to identify their association with cardiorespiratory fitness. Two classes were identified: unhealthy (10.4%), characterized as a high probability of practicing less than 300 min/week of moderate to vigorous physical activity, spending more than 4 h/day in front of screens, and sleeping less than 8 h/day; and healthy (89.6%), characterized by a high probability of practicing more than 420 min/week of moderate to vigorous physical activity, spending less than 2 h/day in front of screens, and sleeping 8-10 h/day. Adolescents in the healthy class had a higher cardiorespiratory fitness level than those in the unhealthy class. Most adolescents were grouped in the healthy class and had higher cardiorespiratory fitness levels than those in the unhealthy class. These results suggest that families and professionals should work toward creating healthier lifestyles for adolescents by increasing opportunities to practice moderate to vigorous physical activity, reduce screen time, and favor healthy sleep to increase their cardiorespiratory fitness levels. What is Known: • Moderate to vigorous physical activity, screen time, and sleep duration are positively, negatively, and inconsistently associated with cardiorespiratory fitness, respectively, when analyzed separately. • Little is known about the clustering of 24-h movement behaviors and how they are associated with cardiorespiratory fitness levels in adolescents. What is New: • The 24-h movement behaviors clustered into almost opposite classes among adolescents (healthy and unhealthy classes). • Adolescents in the healthy class had greater cardiorespiratory fitness levels than those in the unhealthy class.

Prevalence of Brazilian children and adolescents who met health criteria for aerobic fitness: systematic review update for Report Card Brazil Project

abstract The aim of the study was to update Brazilian evidence on the prevalence of children and adolescents who met health criteria for aerobic fitness. This systematic review is part of the Report Card Brazil Project and the search was restricted to studies published during the period from January 2018 to December 2019 in nine electronic databases. Studies with different designs, which allowed extracting information about the prevalence of children and adolescents who met health criteria for aerobic fitness (age up to 19 years or average age up to 19 years) were included. Studies published from 2020 were not included due to the possible effect of the pandemic on this indicator and because there is no certainty as to when the pandemic will end. Of the 694 studies initially identified, 13 studies with information of 14,673 children and adolescents were included after reading titles, abstracts, full texts and references. The prevalence of children and adolescents who met health criteria for aerobic fitness was 26.9% (29.7% for girls; 44.6% for boys). In this search, eight different cutoff points were used to determine adequate aerobic fitness levels and five tests were used to determine aerobic fitness. Analyzing data from the present review with the previous systematic review of this project, one third of children and adolescents in Brazil meet health criteria for aerobic fitness.

Cardiorespiratory fitness in adolescents before and after the COVID-19 confinement: a prospective cohort study

Long periods of free-movement restrictions may negatively affect cardiorespiratory fitness and health. The present study investigated changes after the COVID-19 confinement in maximal oxygen intake (VO₂ max) levels in a sample of 89 Spanish school children aged 12 and 14 years at baseline (49.8% girls). The 20-m shuttle run test served to estimate VO₂ max before and after the COVID-19 confinement. Paired t-tests estimated an overall difference of - 0.5 ml.kg^-1.min^-1 (SD 0.3) (p = 0.12), whereas the highest significant reductions were observed for girls aged 14 years (- 1.5 ml.kg^-1.min^-1 (SD 0.6) (p < 0.05)). Boys aged 14 years showed a slight increase (0.4 ml.kg^-1.min^-1 (SD 0.5) (p = 0.44)), whereas boys aged 12 years presented an important decrease (- 1.2 ml.kg^-1.min^-1 (SD 0.7) (p = 0.14)). Healthy Fitness Zone (HFZ) levels also experienced a decrease of - 3.4% as regards baseline levels over the examined period. All the examined subgroups showed lower levels in relation to a normal VO₂ max rate development, although girls aged 14 and boys aged 12 years accounted for the highest part.Conclusion: The results indicate that COVID-19 confinement might delay the normal development of VO₂ max in adolescents. Strategies to tackle this concerning decline are warranted. What is Known: • First study analyzing cardiorespiratory fitness levels in teenagers after COVID-19 confinement. What is New: • Important delay in maximal oxygen intake identified in a sample of Spanish teenagers. • These results should be considered to develop strategies of a more active lifestyle in teenagers during and after confinements.

Physical fitness attenuates the genetic predisposition to obesity in children and adolescents

Obesity is an important risk factor associated with non-communicable cardiometabolic diseases. Previous studies have indicated that children and adolescents with a predisposed genetic risk for obesity could benefit from an active lifestyle, but there are no studies investigating whether physical fitness moderates the association of genetics and obesity. The aim of this study was to verify the moderating role of physical fitness in the relationship between genetic risk score (GRS) and body mass index (BMI) in children and adolescents. This cross-sectional study was carried out with 1471 children and adolescents, aged between 6 and 17 years from Santa Cruz do Sul, Brazil. Weight and height were assessed to determine BMI. Physical fitness components (cardiorespiratory fitness [CRF], lower limb strength [LLS], upper limb strength, and abdominal strength) were evaluated. The GRS was based on previously associated obesity single-nucleotide polymorphism rs9939609 (FTO), rs6548238 (TMEM18), and rs16835198 (FNDC5). Moderation analyses were tested using linear regression models, and the interactions were represented by physical fitness components X GRS (categorical variable). All analyses were adjusted for skin color/ethnicity, sex, and sexual maturation. Significant interactions for CRF (P = 0.041), LLS (P = 0.041), and abdominal strength (P = 0.046) X 5 and 6 risk alleles with BMI were found only in adolescents. In addition, there was evidence that fitness components attenuated the high genetic predisposition to high BMI. Physical fitness components are moderators in the relationship between GRS and BMI in adolescents. These findings highlight the need for interventions targeting to improve this aspect, which is an important health indicator in all ages.

Health-Related Factors in Rural and Urban Mexican Adolescents from the State of Jalisco: The HELENA-MEX Study

Mexico shows a high prevalence of obesity in children and adolescents. Geographical location and cultural environment could play a role in the promotion of healthy lifestyles in terms of physical activity (PA), sedentary behavior (SB) and nutrition. The purpose of this study was to assess rural and urban differences in body composition (BC), physical fitness (PF), PA and nutritional status of adolescents from the state of Jalisco (Mexico). The study involved 469 students aged 13–17 years (55.0% girls) from eight high schools. BC was analyzed by bioimpedance and PF by standardized field tests. Objective measurements of PA and SB were taken in a subsample (n = 240). Energy intake (EI) was calculated from two 24h recalls. Rural residents presented a higher prevalence of overweight, waist circumference, trunk fat mass, regional fat free mass and muscle handgrip strength (all p < 0.05, η2p < 0.06). Cardiorespiratory fitness was similar among participants, whereas urban adolescents showed higher muscle power, speed-agility and flexibility scores (all p < 0.05, η2p < 0.07). Overall lifestyle behavior in urban adolescents was more sedentary (p < 0.05, η2p = 0.11). EI was similar in both locations. In conclusion, rural Mexican adolescents presented a generally lower sedentary behavior and a lower fitness and fatness profile than their urban peers.

Adiposity Mediates the Association of Objectively Measured Physical Activity with Cardiorespiratory Fitness in Children

Background: The relationship of physical activity (PA) to cardiorespiratory fitness (CRF) is well established in children. However, the extent to which adiposity affects this association remains unclear. Objective: The study aimed to explore whether the relationships of different PA intensities to CRF are explained by adiposity. Methods: Cross-sectional data were collected from 374 children (51.87% boys) aged 7-12 years. The time spent (min/day) in vigorous PA (VPA), moderate PA (MPA), light PA (LPA), and sedentary behavior was objectively measured using triaxial accelerometry. Height, weight, and waist circumference (WC) were objectively measured, from which the BMI was derived. The 20-meter shuttle run test was conducted to estimate maximal oxygen consumption [VO_2max, mL/(kg·min)]. Linear mixed models and mediation analysis with bootstrapping were used to analyze data. Results: VO_2max was positively associated with VPA [β = 0.143, 95% confidence interval (95% CI): 0.091 to 0.194], MPA (β = 0.051, 95% CI: 0.016 to 0.086), and moderate-to-vigorous PA (MVPA) (β = 0.052, 95% CI: 0.029 to 0.075), but not LPA or sedentary time. Both BMI and WC partially mediated the relationships of VPA and MVPA to VO_2max, with the percentage of the total effect mediated by adiposity ranging from 18.0% to 19.6%. Similar results were also observed among boys but not among girls. Conclusions: Only moderate or vigorous intensity of PA is favorably correlated with CRF in children. BMI and WC play a pivotal mediating role in these associations, especially in boys, suggesting that promoting higher intensity of PA might benefit children's CRF through reducing adiposity.

Obesity, the new childhood disability? An umbrella review on the association between adiposity and physical function

The adverse physical impacts of childhood obesity are increasingly being recognized. The objective of this study is to examine relationships between physical function and adiposity in youth. An umbrella review searched seven databases from inception to May 2019 for systematic reviews examining associations between adiposity and physical function in 0-20-year-olds. Findings were synthesized using the International Classification of Functioning, Disability and Health Framework and NHMRC FORM. Seventeen of 21 systematic reviews reported impairments to body function, including cardiorespiratory fitness (CRF), muscle function, balance/coordination, gait biomechanics, pain and injury. Six reviews reported activity restrictions in motor skills, running speed/agility and functional mobility, and two found inverse associations between adiposity and physical health-related quality of life (p-HRQOL). Some causal relationships indicated that adiposity inversely predicted p-HRQOL/CRF and CRF/muscle function inversely predicted adiposity. Assessments of physical function were heterogeneous and impacts on participation in life situations meaningful to the individual were largely unknown. Substantial evidence associates childhood overweight/obesity with reduced physical function. Associations were mainly cross-sectional, with causative evidence for some outcomes. Comprehensive physical function assessments by qualified health professionals are needed, along with targeted interventions to address deficits. Research should further examine causality of relationships, underlying mechanisms and participation challenges in real-life contexts.

Physical activity and health in Chinese children and adolescents: expert consensus statement (2020)

China is experiencing significant public health challenges related to social and demographic transitions and lifestyle transformations following unprecedented economic reforms four decades ago. Of particular public health concern is the fourfold increase in overweight and obesity rates in the nation's youth population, coupled with the low prevalence of adolescents meeting recommended levels of physical activity. Improving the overall health of China's more than 170 million children and adolescents has become a national priority. However, advancing nationwide health initiatives and physical activity promotion in this population has been hampered by the lack of a population-specific and culturally relevant consensus on recommendations for achieving these ends. To address this deficiency and inform policies to achieve Healthy China 2030 goals, a panel of Chinese experts, complemented by international professionals, developed this consensus statement. The consensus was achieved through an iterative process that began with a literature search from electronic databases; in-depth reviews, conducted by a steering committee, of the resulting articles; and panel group evaluations and discussions in the form of email correspondence, conference calls and written communications. Ultimately, the panel agreed on 10 major themes with strong scientific evidence that, in children and adolescents aged 6-17, participating in moderate to vigorous physical activities led to multiple positive health outcomes. Our consensus statement also (1) highlights major challenges in promoting physical activity, (2) identifies future research that addresses current knowledge gaps, and (3) provides recommendations for teachers, education experts, parents and policymakers for promoting physical activity among Chinese school-aged children and adolescents. This consensus statement aligns with international efforts to develop global physical activity guidelines to promote physical activity and health and prevent lifestyle-related diseases in children and adolescents. More importantly, it provides a foundation for developing culturally appropriate and effective physical activity interventions, health promotion strategies and policy initiatives to improve the health of Chinese children and adolescents.

Physical Activity Recommendations for Segments of School Days in Adolescents: Support for Health Behavior in Secondary Schools

School physical activity (PA) is an indispensable part of daily PA, the foundation for developing lifelong PA and fitness, and an easy way to gain physical and health literacy. School PA is equally important for understanding the continuity of physical and mental health, even in broader psychosocial aspects. Regarding long-term outcomes, significant attention has been paid to the determination of daily and weekly recommendations for adolescent PA. However, comprehensive approaches suggesting recommendations for PA in segments of the school day are rare. This study aimed to (a) provide a rationale for PA recommendations in segments of school days and incorporate it into generally accepted PA recommendations, and (b) promote radical changes in the educational process toward a healthy school lifestyle through PA recommendations in segments of school days. The results of research conducted in 98 secondary schools in the Czech Republic and 104 secondary schools in Poland from 2009 to 2017 were used in this study. In total, 3,860 boys and 5,237 girls from the Czech Republic and 3,052 boys and 3,329 girls from Poland, all aged 15-19, participated. We recommended at least 2,000 steps (or 10 min of moderate-to-vigorous PA) for the before school segment and at least 6,000 steps (or 30 min of moderate-to-vigorous PA) for the after-school segment. For the time spent at school, we further recommended at least 500 steps/h (alternatively, at least 3,000 steps/school time), 20 min of moderate-to-vigorous PA (≥3METs or 60% HRmax), and at least one HRsubmax/max response to significant stress during PA to mitigate educational stress and high levels of sedentary behavior in schools. PA should account for at least 25% of school time, even on days with no scheduled physical education lessons. We propose using PA recommendations in segments of school days to achieve positive changes in the educational process and school lifestyle. Acceptance of PA recommendations in segments of school days theories on physical education could help refine and concretize demands for changes in PA and lifestyle in secondary schools. In practice, it could support the creation of innovative and comprehensive school PA programs. Future research should focus on obtaining evidence in support for adolescent PA by applying PA recommendations in segments of school days.

Effects of dancing on physical activity levels of children and adolescents: a systematic review

BACKGROUND

Dancing has been suggested to increase the levels of physical activity of the youth. However, it is not clear what are the physiological characteristics of the dance classes for young people, mainly regarding the levels of moderate to vigorous physical activity (MVPA) during classes. It is also unclear if regular engagement in dance practices can contribute with increases in the amounts of daily/weekly MVPA, recommended by health organizations.

OBJECTIVES

To conduct a systematic review verifying the amount of time spent at MVPA (primary outcome), by children and adolescents in the following situations: i) During dance classes, and ii) Before and after dance interventions. Secondary outcomes included: markers of exercise intensity during class, such as oxygen consumption (VO₂) and heart rate (HR); VO₂peak and lipid profile before and after dance interventions.

METHODS

Six data sources were accessed (MEDLINE, EMBASE, Cochrane Wiley, PEDRO and SCOPUS). Study selection included different designs (acute, cohort, randomized controlled trials and others). Participants were from 6 to 19 years old, regularly engaged in dance practices. Methodological quality was assessed using the Downs and Black checklist. Two independent reviewers extracted characteristics and results of each study.

RESULTS

3216 articles were retrieved, and 37 included. Studies indicated that dance classes do not achieve 50% of total class time at MVPA. However, there are peaks of HR and VO₂ during dance classes, which reach moderate and vigorous intensities. MVPA/daily/weekly did not improve before and after dance interventions for most of the studies, also VO₂peak did not. The few results on lipid profile showed improvements only in overweight and obese participants.

LIMITATIONS

Lack of meta-analysis, because there were not enough articles to be analyzed on any given outcome of interest, neither under the same study design.

CONCLUSIONS

Results of individual studies indicated that dance classes did not active 50% of the total time at MVPA levels. This may be related to the absence of improvements in daily/weekly MVPA before and after dance interventions. VO₂ and HR attained peaks of moderateto vigorous intensity during dance classes, suggesting that the structure of the classes may be manipulated to maintain longer periods at MVPA levels. Lack of data on cardiorespiratory fitness and metabolic outcomes limit conclusions on these parameters.

IMPLICATIONS OF KEYS FINDS

Considering there are peaks of HR and VO₂ during dance classes, we suggest that the structure of a dance class can be manipulate in order to induce cardiorespiratory and metabolic adaptations. Thus, dancing is a potential strategy to contribute with a healthy life style since the earliest ages. Prospero registration: CRD42020144609.

Association of Cardiorespiratory Fitness Levels During Youth With Health Risk Later in Life: A Systematic Review and Meta-analysis

IMPORTANCE

Although the associations between cardiorespiratory fitness (CRF) and health in adults are well understood, to date, no systematic review has quantitatively examined the association between CRF during youth and health parameters later in life.

OBJECTIVES

To examine the prospective association between CRF in childhood and adolescence and future health status and to assess whether changes in CRF are associated with future health status at least 1 year later.

DATA SOURCES

For this systematic review and meta-analysis, MEDLINE, Embase, and SPORTDiscus electronic databases were searched for relevant articles published from database inception to January 30, 2020.

STUDY SELECTION

The following inclusion criteria were used: CRF measured using a validated test and assessed at baseline and/or its change from baseline to the end of follow-up, healthy population with a mean age of 3 to 18 years at baseline, and prospective cohort design with a follow-up period of at least 1 year.

DATA EXTRACTION AND SYNTHESIS

Data were processed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Random-effects models were used to estimate the pooled effect size.

MAIN OUTCOMES AND MEASURES

Anthropometric and adiposity measurements and cardiometabolic health parameters.

RESULTS

Fifty-five studies were included with a total of 37 563 youths (46% female). Weak-moderate associations were found between CRF at baseline and body mass index (r = -0.11; 95% CI, -0.18 to -0.04; I2 = 59.03), waist circumference (r = -0.29; 95% CI, -0.42 to -0.14; I2 = 69.42), skinfold thickness (r = -0.34; 95% CI, -0.41 to -0.26; I2 = 83.87), obesity (r = -0.15; 95% CI, -0.23 to -0.06; I2 = 86.75), total cholesterol level (r = -0.12; 95% CI, -0.19 to -0.05; I2 = 75.81), high-density lipoprotein cholesterol (HDL-C) level (r = 0.11; 95% CI, 0.05-0.18; I2 = 69.06), total cholesterol to HDL-C ratio (r = -0.19; 95% CI, -0.26 to -0.13; I2 = 67.07), triglyceride levels (r = -0.10; 95% CI, -0.18 to -0.02; I2 = 73.43), homeostasis model assessment for insulin resistance (r = -0.12; 95% CI, -0.18 to -0.06; I2 = 68.26), fasting insulin level (r = -0.07; 95% CI, -0.11 to -0.03; I2 = 0), and cardiometabolic risk (r = -0.18; 95% CI, -0.29 to -0.07; I2 = 90.61) at follow-up. Meta-regression analyses found that early associations in waist circumference (β = 0.014; 95% CI, 0.002-0.026), skinfold thickness (β = 0.006; 95% CI, 0.002-0.011), HDL-C level (β = -0.006; 95% CI, -0.011 to -0.001), triglyceride levels (β = 0.009; 95% CI, 0.004-0.014), and cardiometabolic risk (β = 0.007; 95% CI, 0.003-0.011) from baseline to follow-up dissipated over time. Weak-moderate associations were found between change in CRF and body mass index (r = -0.17; 95% CI, -0.24 to -0.11; I2 = 39.65), skinfold thickness (r = -0.36; 95% CI, -0.58 to -0.09; I2 = 96.84), obesity (r = -0.21; 95% CI, -0.35 to -0.06; I2 = 91.08), HDL-C level (r = 0.05; 95% CI, 0.02-0.08; I2 = 0), low-density lipoprotein cholesterol level (r = -0.06; 95% CI, -0.11 to -0.01; I2 = 58.94), and cardiometabolic risk (r = -0.08; 95% CI, -0.15 to -0.02; I2 = 69.53) later in life.

CONCLUSIONS AND RELEVANCE

This study suggests that early intervention and prevention strategies that target youth CRF may be associated with maintaining health parameters in later life.

Well-Being, Physical Fitness, and Health Profile of 2,203 Danish Girls Aged 10-12 in Relation to Leisure-time Sports Club Activity-With Special Emphasis on the Five Most Popular Sports

Madsen, M, Larsen, MN, Cyril, R, Møller, TK, Madsen, EE, Ørntoft, C, Lind, RR, Ryom, K, Christiansen, SR, Wikman, J, Elbe, AM, and Krustrup, P. Well-being, physical fitness, and health profile of 2,203 Danish girls aged 10-12 in relation to leisure-time sports club activity-with special emphasis on the five most popular sports. J Strength Cond Res XX(X): 000-000, 2020-This study investigated the relationship between leisure-time sports club activities and well-being as well as physical health parameters in 10-12-year-old Danish girls. Two thousand two hundred three girls took part in the study, which included questionnaires on participation in leisure-time sports clubs, well-being, Yo-Yo intermittent recovery level 1 children's test, long jump, balance tests, body composition, blood pressure (BP), and resting heart rate (RHR). Data were analyzed according to whether the girls participated in leisure-time sport and according to the 5 most frequently reported sports. Girls enrolled in leisure-time sports had higher physical well-being (49.3 ± 8.6 vs. 45.2 ± 8.3), psychological well-being (50.4 ± 9.0 vs. 49.4 ± 9.8), experienced more peer and social support (50.2 ± 10.0 vs. 48.9 ± 10.7), and perceived a more positive school environment (52.5 ± 8.0 vs. 50.5 ± 9.3), as well as showing higher Yo-Yo (+39%), long jump (+10%), and balance performance (+15%) than girls not involved in sport clubs. The girls active in sports clubs had higher relative muscle mass (+5%), lower fat percentage (-11%), body mass index (-5%), RHR (-3.4 b·min), and diastolic BP (-1.4 mm Hg) compared with girls not involved in sport (p < 0.05). Girls who played soccer showed higher aerobic fitness compared with inactive girls (+67%), dancers (+39%), swimmers (+38%), and gymnasts (+16%). Gymnasts had a lower fat percentage than inactive girls (-19%), team handballers (-10%), swimmers (-12%), and soccer players (-4%). Girls participating in club-based leisure-time sports showed higher well-being and better fitness and health profiles than girls not involved in any sports club activities. Girls involved in soccer had better aerobic fitness and gymnasts a lower fat percentage.

The association of dietary patterns and cardiorespiratory fitness: A systematic review

AIMS

In comparison to the traditional risk factors of cardiovascular diseases, little is known about the interaction between diet and cardiorespiratory fitness (CRF). The present systematic review aimed to provide comprehensive evidence regarding the relationship between the dietary patterns (DPs) with CRF in both children and adults.

DATA SYNTHESIS

Databases of PubMed, Scopus, and Web of Science were searched from inception up to December 2019. All observational studies that had extracted DPs using a posteriori and/or a priori methods, as well as had assessed CRF as the outcome, were eligible for inclusion in the review. Eleven studies (1 longitudinal and 10 cross-sectional studies) comprising a total of 198,271 subjects were included. There was considerable heterogeneity between studies in terms of the extracted DPs, their food items as well as the statistical reporting outcomes; which all made comparisons between the studies difficult. Despite some inconsistent results, overall there was a positive association between the DPs that were highly loaded with fruits and vegetables, as well as closer adherence to the high-quality diets particularly the Mediterranean diet, with higher values of CRF. While, an inverse association was found for unhealthy DPs that were generally characterized by a high intake of refined grains, sweets, meats, processed foods, and high-fat dairy products.

CONCLUSION

Overall, the evidence indicates the high-quality diets that are highlighted in the national dietary guidelines are associated with an optimal CRF. However, these findings should be confirmed by rigorous prospective and interventional studies.

Effects of Exercise Intervention on Health-Related Physical Fitness and Blood Pressure in Preschool Children: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

No previous systematic review has quantitatively examined the effect of physical exercise interventions on health-related physical fitness and blood pressure in children younger than 6 years old.

OBJECTIVE

To evaluate the effects of exercise interventions on health-related physical fitness (i.e., physical fitness components and body composition) and blood pressure in preschoolers.

METHODS

We searched four databases. Only randomized controlled trials (RCTs), evaluating the effectiveness of exercise intervention on weight-related outcomes, blood pressure, and physical fitness components in preschoolers (1-5.99 years old) were included. The effect sizes were reported as Hedges' g using random-effects models.

RESULTS

A total of 19 RCTs were included. Exercise interventions favored reductions in body mass index (g = - 0.17; 95% confidence interval [CI], - 0.31 to - 0.03), waist circumference (g = - 0.25; 95% CI - 0.47 to - 0.03), and body fat percentage (g = - 0.31; 95% CI - 0.60 to - 0.23); as well as improvement in cardiorespiratory fitness (g = 0.25; 95% CI 0.08-0.42), muscular strength (g = 0.25; 95% CI 0.09-0.40), and speed-agility (g = - 0.51; 95% CI - 0.78 to - 0.24). Blood pressure was not reduced. The subgroup analysis revealed that physical exercise alone favored larger reductions in body mass index and waist circumference compared with physical exercise combined with another intervention. Also, changes in cardiorespiratory fitness, lower-body muscular strength and speed-agility were associated with larger decreases in body composition.

CONCLUSION

Physical exercise whether combined or not with additional intervention has a small effect on both body weight and physical fitness in preschoolers. Also, it seems that interventions to prevent obesity should be directed towards improving physical fitness of preschoolers.

Associations between physical activity, body composition, and physical fitness in the transition from preschool to school

The purpose of the study was to assess the longitudinal associations of physical activity (PA) with body composition and physical fitness (PF) at the 12-month follow-up during the transition from kindergarten to school in Estonian children aged 6 to 8 years (n = 147). PA and sedentary behavior (SB) were assessed using the accelerometer. Body composition was measured from triceps and subscapular skinfold thicknesses and PF using PREFIT test battery. SB at the mean age of 6.6 year had negative relation with upper and lower body strength and motor fitness at the mean age of 7.6 year in adjusted models. Light PA (LPA) and moderate PA(MPA) at 6.6 year were positively and SB was negatively associated with fat-free mass index (FFMI) at 7.6 year after adjustments for confounders [vigorous PA (VPA), total awake wear time, child's sex, age at measurement]. Substituting 5 min/d of SB at 6.6 year with 5 min of VPA was related to higher FFMI at 7.6 year. In adjusted models, VPA at 6.6 year was positively associated with cardiorespiratory fitness at 7.6 year, greater baseline VPA or moderate-to-vigorous PA (MVPA) predicted greater upper body strength a year later and LPA, MPA, VPA, MVPA at 6.6 year were positively related to lower body strength at follow-up. In adjusted analysis greater VPA at 6.6 year was related to better motor fitness at follow-up. Promoting higher-intensity PA and reducing SB at preschool may have long-term effects on body composition and PF in children at the first grade.

Effects of 2 Methods of Combined Training on Cardiometabolic Risk Factors in Adolescents: A Randomized Controlled Trial

PURPOSE

To analyze the effects of 2 combined training methods on the cardiometabolic risk factors in adolescents.

METHODS

A total of 76 adolescents (16.1 [1.1] y, n = 44 female) were randomized into groups of moderate-intensity continuous training combined with resistance training (MICT + RT), high-intensity interval training combined with resistance training (HIIT + RT), or control. The training sessions were performed twice weekly for 12 weeks. The outcomes evaluated included body fat percentage, waist circumference, fasting blood glucose, fasting insulin, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein, glycated hemoglobin, insulin resistance index, blood pressure, peak oxygen consumption (VO2peak), and cardiometabolic risk Z score.

RESULTS

The intervention groups presented a significant reduction in the cardiometabolic risk Z score after 12 weeks of the combined exercise program. In relation to the cardiometabolic risk Z score between groups, the HIIT + RT group presented a significant intervention effect when compared with the control group (Cohen d = 0.23; P < .05). Significant intervention effects were found when comparing the MICT + RT and control groups for body fat percentage, high-density lipoprotein, and VO2peak. Between the HIIT + RT and control groups, significant intervention effects were found for body fat percentage, blood pressure, and VO2peak. There were not significant differences between the HIIT + RT and MICT + RT groups.

CONCLUSION

Twelve weeks of HIIT + RT and MICT + RT were effective in significantly reducing the cardiometabolic risk in these adolescents.

Population-based trends in physical fitness of children and adolescents in Germany, 2003-2017

Physical fitness is an important health resource. From 2003 onwards, the MoMo study, a part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), has investigated physical fitness on the basis of nationally representative data. The objective of this paper was to analyse trends in physical fitness of three cohorts at the ages of 4-17 years. Changes within 10 test items of the MoMo-test profile are reported. The mean values of physical fitness and the relevant influencing factors were directly compared across cohorts (in the total group and in age-and sex-subgroups). Statistical significance of differences was examined by calculating the confidence intervals (95% CI) for complex samples; effect sizes were determined using Cohen's d. The results indicated that physical fitness levels of German children and adolescents initially slightly increased between MoMo baseline (2003-2006) and wave 1 (2009-2012). This could partly be attributed to increased physical activity in sports clubs and in extracurricular sports at school. Then, between MoMo wave 1 and MoMo wave 2 (2014-2017) the physical fitness of children and adolescents in Germany remained the same, as did all influencing factors with the exception of extracurricular sport. From a public health perspective, programmes and measures that can increase the chances for all children and adolescents to strive for greater physical fitness should be of the highest priority.

Genetics of somatotype and physical fitness in children and adolescents

OBJECTIVES

To analyze the influence of genetic and environmental factors on the variation in somatotype, physical fitness, and their mutual associations.

METHODS

Twins from 214 pairs (87 monozygotic) of the Autonomous Region of Madeira, Portugal, from 3 to 18 years of age (51% girls) were assessed in anthropometry and physical fitness tests. We estimated endomorphy, mesomorphy, and ectomorphy based on anthropometric measures and physical fitness using the Eurofit test battery. Two age categories were analyzed: children (3-11 years) and adolescents (12-18 years). Genetic and environmental variations were estimated using quantitative genetic twin modeling.

RESULTS

No genetic sex differences were found, thus boys and girls were pooled in all genetic analyses. Heritability estimates were high for somatotype (a²  = 0.80-0.93), physical fitness traits (a²  = 0.67-0.83), and largely similar in children and adolescents. Positive correlations were found for ectomorphy with motor ability and cardiorespiratory endurance as well as for endomorphy and mesomorphy with muscular strength (r = 0.25-0.37). In contrast, negative associations were found for ectomorphy with muscular strength, as well as for endomorphy and mesomorphy with motor ability and cardiorespiratory endurance (-0.46 to -0.26). Twin modeling indicated that these associations were explained mostly by genetic factors in common to the two associated traits (84% or more).

CONCLUSIONS

Associations between somatotype and physical fitness tests are mainly explained by common genetic background in children and adolescents. Therefore, interventions in youth should consider that a child's performance in physical fitness tests partly reflects their inherited physique.

Health-related physical fitness indicators and clustered cardiometabolic risk factors in adolescents: A longitudinal study

Background/Objective

This study examined relationships between health-related physical fitness indicators and clustered cardiometabolic risk factors in adolescents between 2014 and 2017.

Methods

The sample consisted of 93 students (60% girls), with complete data sets in both 2014 and 2017. The physical fitness components evaluated were: flexibility (sit and reach), muscular fitness (curl-up and push-up), cardiorespiratory fitness (progressive aerobic cardiovascular endurance run), and body fat (BMI). The cardiometabolic risk factors were: waist circumference, blood pressure, high-density lipoprotein cholesterol (HDL-C), triglycerides and fasting blood glucose. Z-scores were calculated for each risk factor, with the sum of risk factor z-scores values used to represent clustered cardiometabolic risk.

Results

The results of cross-sectional analysis indicated that muscle fitness (curl-up: β = −0.37, p < 0.001; push-up: β = −0.38, p < 0.005) and cardiorespiratory fitness (β = −0.56, p < 0.001) were inversely associated with clustered cardiometabolic risk, with BMI positively associated (β = 0.58, p < 0.001). In the longitudinal analysis, cardiorespiratory fitness (β = −0.33; p < 0.005) and body fat (β = 0.46, p < 0.001) demonstrated a significant association with clustered cardiometabolic risk. However, no significant associations between the health-related physical fitness and clustered cardiometabolic risk were observed after adjustment for baseline values.

Conclusion

Our cross-sectional findings highlight the importance of health-related physical fitness indicators to adolescents. In regarding the longitudinal analysis, further studies are needed in order to clarify the influence of physical fitness in the adolescence and cardiometabolic risk later in life.

Association of Physical Education With Improvement of Health-Related Physical Fitness Outcomes and Fundamental Motor Skills Among Youths: A Systematic Review and Meta-analysis

IMPORTANCE

Whether quality- or quantity-based physical education (PE) interventions are associated with improvement of health-related physical fitness outcomes and fundamental motor skills (FMSs) in children and adolescents is unknown.

OBJECTIVE

To examine the association of interventions aimed at optimizing PE in terms of quality (teaching strategies or fitness infusion) or quantity (lessons per week) with health-related physical fitness and FMSs in children and adolescents.

DATA SOURCES

For this systematic review and meta-analysis, studies were identified through a systematic search of Ovid MEDLINE, Embase, Cochrane Controlled Trials Registry, and SPORTDiscus databases (from inception to October 10, 2019) with the keywords physical education OR PE OR P.E. AND fitness AND motor ability OR skills. Manual examination of references in selected articles was also performed.

STUDY SELECTION

Studies that assessed the association of quality- or quantity-based PE interventions with improvement in physical fitness and/or FMSs in youths (aged 3-18 years) were included.

DATA EXTRACTION AND SYNTHESIS

Data were processed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Random-effects models were used to estimate the pooled effect size (Hedges g).

MAIN OUTCOMES AND MEASURES

Health-related physical fitness outcomes and FMSs.

RESULTS

Fifty-six trials composed of 48 185 youths (48% girls) were included in the meta-analysis. Quality-based PE interventions were associated with small increases in health-related physical fitness (cardiorespiratory fitness [Hedges g = 0.24; 95% CI, 0.16-0.32] and muscular strength [Hedges g = 0.19; 95% CI, 0.09-0.29]) and FMSs (Hedges g = 0.38; 95% CI, 0.27-0.49). Subgroup analyses found stronger associations for quality-based PE interventions on body mass index (Hedges g = -0.18; 95% CI, -0.26 to -0.09), body fat (Hedges g = -0.28; 95% CI, -0.37 to -0.18), cardiorespiratory fitness (Hedges g = 0.31; 95% CI, 0.23-0.39), and muscular strength (Hedges g = 0.29; 95% CI, 0.18-0.39). Quantity-based PE interventions were associated with small increases in only cardiorespiratory fitness (Hedges g = 0.42; 95% CI, 0.30-0.55), muscular strength (Hedges g = 0.20; 95% CI, 0.08-0.31), and speed agility (Hedges g = 0.29; 95% CI, 0.07-0.51).

CONCLUSIONS AND RELEVANCE

The findings suggest that quality-based PE interventions are associated with small increases in both student health-related physical fitness components and FMSs regardless of frequency or duration of PE lessons. Because PE aims to improve more than health, high levels of active learning time may need to be balanced with opportunities for instruction, feedback, and reflection.

Higher Cardiorespiratory Fitness Levels May Attenuate the Detrimental Association between Weight Status, Metabolic Phenotype and C-Reactive Protein in Adolescents-A Multi-Cohort Study

Results from several studies show that only obese, unfit subjects, but not obese, fit subjects, are at higher mortality risk than are normal-weight fit subjects. The aim of the study was two-fold: (1) to examine the differences in C-reactive protein levels across different metabolic phenotypes (healthy and unhealthy) of weight status and (2) ascertain whether high levels of cardiorespiratory fitness (CRF) attenuate the association of C-reactive protein and metabolic phenotypes of weight status. This was a pooled study, which included data from three cross-sectional projects (1706 youth (921 girls) aged 12-18 years). We used a Shuttle run test to assess CRF. Adolescents were classified into six metabolic phenotypes (healthy and unhealthy) of weight status (non-overweight, overweight and obese), based on age- and sex-specific cutoff points for triglycerides, systolic blood pressure, HDL-cholesterol, glucose and body mass index. High-sensitivity assays were used to obtain the C-reactive protein as inflammatory biomarker. After adjustment for potential confounders (age, sex, pubertal stage and country), the analysis of covariance (ANCOVA) shows that C-reactive protein is directly associated with metabolic phenotypes of weight status. Subjects with obesity, regardless of their metabolic profile, had higher levels of C-reactive protein Z-score. In addition, (after adjustments for potential confounders) a two-way ANCOVA showed that high levels of CRF attenuated the associations of C-reactive protein levels in metabolic healthy non-overweight and in adolescents with obesity. In conclusion, higher CRF levels may attenuate the detrimental association between obesity and C-reactive protein independently of metabolic phenotype. Findings from this study are important for prevention, clinical practice on issues associated with adiposity and metabolic disorders.

Testing validity of FitnessGram in two samples of US adolescents (12-15 years)

Background

This study examined the validity of the FitnessGram® criterion-reference cut-points for cardiorespiratory fitness (CRF) based on two samples of US adolescents (aged 12–15 years). This study also established the CRF cut-points for metabolically healthy weight status based on a recent national fitness survey for the purposes of cross-validating with pre-existing cut-points including FitnessGram.

Methods

Two cross-sectional data from the 2003–2004 National Health and Nutrition Examination Survey (NHANES) (n = 378) and 2012 NHANES National Youth Fitness Survey (NNYFS) (n = 451) were used. CRF (estimated V˙O_2max in mL/kg/min) was estimated from a submaximal exercise test. CRF categories based on FitnessGram cut-points, a clustered cardiometabolic risk factors score and weight status were used. A series of Receiver Operating Characteristic (ROC) curve analyses were conducted to identify age- and sex-specific CRF cut-points that were optimal for metabolically healthy weight status.

Results

Based on FitnessGram cut-points, having high risk CRF, but not low risk CRF, was associated with high cardiometabolic risk (OR = 3.17, 95% CI = 1.14–8.79) and unhealthy weight status (OR = 5.81, 95% CI = 3.49–9.68). The optimal CRF cut-points for 12-13-year-olds and 14-15-year-olds were 40 and 43 mL/kg/min in males and 39 and 34 mL/kg/min in females, respectively. Compared to meeting new CRF cut-points, not meeting new CRF cut-points was associated with higher odds of showing high cardiometabolic risk (OR = 2.91, 95% CI = 1.47–5.77) and metabolically unhealthy weight status (OR = 4.47, 95% CI = 2.83–7.05).

Conclusion

FitnessGram CRF cut-point itself has rarely been scrutinized in previous literature. Our findings provide partial support for FitnessGram based on two samples of US adolescents. CRF cut-points established in this study supports international criterion-referenced cut-points as well as FitnessGram cut-points only for males. FitnessGram should be continuously monitored and scrutinized using different samples.

Influencing factors of obesity in school-age children and adolescents - A systematic review of the literature in the context of obesity monitoring

Around 15% of children and adolescents in Germany are overweight or obese. To support the planning, implementation and evaluation of preventive activities, the Robert Koch Institute (RKI) has developed a population-wide monitoring of influencing factors relevant to the development of obesity during childhood (AdiMon). AdiMon is a web-based indicator system providing population-wide meaningful and regularly updated data on factors that influence obesity in kindergarten-age girls and boys (0- to 6-years-old). Towards the end of 2020, the RKI will expand the indicator system to also cover the 7- to 17-year-old age group. To this end, a systematic review of the literature was conducted, a process which served to identify over 80 relevant factors that influence the development of obesity. These factors have been attributed to the categories behaviour, environment, biology, pre- and postnatal, psychosocial factors and context. Compared to a previous literature review for kindergarten-age children, around one tenth of the influencing factors now identified are new, including 'peer group influences' and 'bullying'. As the results highlight, an array of influencing factors must be considered when expanding the monitoring system, ranging from individual health behaviour to the social framework conditions and environmental factors.