Active and strong: physical activity, muscular strength, and metabolic risk in children

Are accelerometer-measured sitting and physical activity times associated with muscle mass and strength in healthy young adults in the UAE?

Background

A high prevalence of obesity, sedentary behavior, and physical inactivity could affect muscle mass and strength in young adults in the United Arab Emirates (UAE). Therefore, we investigated the association of sex, body mass index (BMI), and accelerometer-measured sitting and physical activity (PA) times with skeletal muscle mass index (SMI), hand grip, and thigh muscle strength in healthy young adults in the UAE.

Methods

In this cross-sectional study, 156 healthy young adults (age 21.68 ± 3.01 years, BMI 25.40 ± 4.79 kg/m2, 52.6 % women) were included. BMI and muscle mass were recorded using a bioelectrical impedance analyzer. Maximum hand grip strength and thigh muscle torque were assessed using the Jamar-smart hand-dynamometer and Biodex System-4-Pro, respectively. Participants wore a triaxial Fibion accelerometer on their anterior thigh for >10 h per day for 4-7 days to measure their sitting and PA times. Multiple linear regression analyses were used.

Results

Participants spent most of their time sitting (11.37 ± 1.10 h), followed by standing (2.92 ± 0.86 h), walking (1.58 ± 0.55 h), and vigorous intensity PA (4.79 ± 5.85 min) per 16-h day. Sex (p < 0.001) and BMI (p < 0.001) were negatively associated with all muscle mass and strength variables. Men had more muscle mass and strength than women. As BMI increased, muscle mass and muscle strength decreased. Accelerometer-measured sitting and walking times were negatively associated with concentric hamstrings (p = 0.044) and quadriceps torques (p = 0.031), respectively.

Conclusion

Sex, BMI, and accelerometer-measured sitting and walking times were associated with muscle mass and/or muscle strength in healthy young adults. Women and those with a high BMI need interventions to improve their muscle mass and strength. The paradox regarding the association of PA with muscle mass and strength in younger adults may be due to possible influences from other factors (e.g., resistance training, dietary intakes, etc.) superseding that of accelerometer-measured PA.

Association between Gross Motor Competence and Physical Fitness in Chilean Children Aged 4 to 6 Years

The preschool period is considered critical for the development of motor competence, but as far as we know, no studies have investigated the association between motor competence and physical fitness in Chilean children. The aim of this study was to analyse the association between gross motor competence and physical fitness, controlling for possible confounding factors. A cross-sectional study was conducted with a sample of 144 preschool children (56.25% girls) with an average age of 5.3 years (4 to 6 years) from the Araucanía region, Chile. Motor competence was measured using the Children's Movement Assessment Battery, 2nd Edition (MABC-2). Regarding physical fitness, the components of cardiorespiratory fitness, lower body muscle strength and speed/agility were evaluated using the Battery to Assess FITness in PREschool (PREFIT). Partial correlation models and analysis of variance (ANCOVA) were used to assess differences in physical fitness between motor competence categories, controlling for age and body mass index. The mean fitness scores for cardiorespiratory fitness, lower body muscle strength and speed/agility components were significantly higher in children with higher gross motor competence. In terms of effect size, large values were found for the lower body strength component in model 1 for boys and in model 2 for the total samples of girls and boys. The results of this study suggest that good levels of gross motor competence are associated with better physical fitness levels.

Physical Activity Is Associated with Physical Fitness and Executive Function among School Children in the Jiangxi Region of China

Previous studies have suggested that a positive relationship exists between physical activity (PA), physical fitness, and cognitive function in children and adolescents. However, research remains limited on the relationship among these three variables in Chinese individuals not living in big cities or specific regions. Therefore, this study investigated the association of PA with physical fitness and cognitive function (specifically, executive function) among 1100 children aged 9-12 years living in the Jiangxi region of China. Participants' PA levels were measured using the PA questionnaire for older children. Physical fitness was assessed based on cardiorespiratory endurance, muscle strength, muscular endurance, flexibility, and body mass index (BMI). Executive function was assessed using the Behavior Rating in Inventory of Executive Function questionnaire. Data were analyzed using one-way analyses of variance, Scheffé tests, one-way analyses of covariance, and Pearson's correlation coefficients. The results showed that PA is significantly associated (p < 0.01) with cardiorespiratory endurance (r = 0.460), muscular endurance (r = 0.270), muscle strength (r = 0.190), BMI (r = -0.114), and executive function (r = -0.140). Moreover, all components of physical fitness and executive function differed significantly based on PA level, with and without age and sex as covariates (p < 0.05). Overall, our results highlight the importance of higher PA levels during childhood to improve physical fitness and cognitive function. Including the goal of improving health-related fitness factors, such as cardiorespiratory endurance and muscle strength, is particularly important in PA programs for children.

Combined Physical Training Strategies Improve Physical Fitness, Behavior, and Social Skills of Autistic Children

The present study aimed to investigate the effects of combined physical training (CPT) on social skills and physical fitness (PF) in children with ASD. Sixteen children with autism (age 6-10 years) were randomly assigned into two groups: CPT and control. The CPT group participated in a program involving ball game, rhythmic movements, and resistance training for eight weeks (three sessions per week). PF and behavior profile were assessed before and after training. CPT program had a significant effect on indicators of social skills such as stereotypic behavior and communication, as well as PF such as handgrip strength, upper and lower body power, flexibility, balance, and agility (P < 0.05). CPT in autistic children can improve indicators of social skills and PF.

The Association between Sedentary Behavior, Physical Activity, and Physical Fitness with Body Mass Index and Sleep Time in Chilean Girls and Boys: A Cross-Sectional Study

BACKGROUND

In recent decades, the school population has undergone behavioral changes that have affected their health and adult life. The current educational scenario presents high levels of sedentary behavior, physical inactivity, low physical fitness, high levels of obesity, and non-compliance with sleep recommendations. In Chile, the scientific evidence on associations between these behaviors is incipient.

OBJECTIVE

To analyze the association between sedentary behavior, physical activity, and physical fitness with BMI and minutes of sleep in Chilean children aged 10 to 11 years.

METHODS

A non-probabilistic convenience sample of 222 schoolchildren aged 10 to 11 years. The variables measured were body composition (BMI), cardiorespiratory fitness (20 m shuttle run test), lower and upper muscular strength (long jump test and handgrip dynamometry), speed (4 × 10 m running), and flexibility (sit and reach test). Physical activity and sleep were measured by accelerometers.

RESULTS

Of the participants, 60.4% and 90.6% did not comply with sleep and physical activity recommendations, respectively. Physical fitness was higher in boys in all components. The results of the linear regression show that in girls, moderate-vigorous-intensity physical activity, lower- and upper-body muscular strength, and cardiorespiratory endurance were associated with BMI and sleep. In boys, light-intensity physical activity and upper-body muscular strength were associated with both variables.

CONCLUSIONS

Physical activity intensity, strength, and cardiorespiratory fitness were associated with BMI and sleep; however, physical activity intensity and associated physical fitness components differed by gender.

Physical Inactivity Levels of European Adolescents in 2002, 2005, 2013, and 2017

Sport and Physical Activity (PA) Special Eurobarometer surveys may inform of the physical inactivity (PIA) levels in the European Union (EU). This study aimed to analyse the PIA levels of EU adolescents (15-17 years) in four time points, according to gender. The data were from 2002, 2005, 20013, and 2017 Special Eurobarometers. Adolescents were categorised as "Inactive" when performing less than 60 min/day of moderate to vigorous PA on average. A χ2 test was used to compare the levels of PIA between survey years. PIA levels between gender were analysed using a Z-score test for two population proportions. PIA levels ranged from 67.2% for boys (59.4% to 71.5%;) to 76.8% for girls (76.0% to 83.4) across the time points. Adjusted standardised residuals revealed a decrease in the observed levels versus the expected for 2005 (whole sample: -4.2; boys: -3.3) and an increase for 2013 (whole sample: +2.9; boys: +2.5). Boys presented lower PIA levels than girls in all years (p ≤ 0.003), but descriptively, the difference progressively decreased (from 18.4% to 11.8%). No significant reductions in PIA levels were observed between 2002 and 2017, and girls reported consistently higher levels of PIA than boys.

Effectiveness of a physical activity intervention on the overweight and obesity of Chilean schoolchildren

INTRODUCTION

Physical fitness is considered a measure that integrates most of the functions of the human organism that are involved in physical activity. Motor competence is important due to its observed implications in the physical, mental and social development of children and adolescents. These assessments require the existence of updated reference values that allow the categorization of individuals and groups according to levels of physical fitness and motor competence. This paper describes the study protocol to Effectiveness of a Physical Activity Intervention on the Overweight and Obesity of Chilean Schoolchildren, and in this way determine, through the calculation of a representative sample, reference values for physical fitness and motor competence in children aged 4 to 6 years in the region of La Araucanía, Chile.

METHODS

children in pre-basic education in transition grades I and II (4 and 5 years old), and those in the first year of basic education (6 years old) will be invited to participate. The sample will be probabilistic. The measures of a randomized controlled trial (registered in ClinicalTrial.gov NCT04194580) will be used.

CONCLUSION

the lack of reference values for physical condition and motor competence for children between 6 and 4 years of age in the Araucanía region highlights the need to establish values, which will contribute to improving the health of children of the age group to be worked on.

Physical Activity and Exercise Practice to Reduce the Sedentary Behavior in Children and Adolescents Overweight and with Obesity

Childhood obesity remains a serious public health concern all over the world [...]

The association of stress and physical activity: Mind the ecological fallacy

Psychological stress and physical activity are interrelated, constituting a relevant association to human health, especially in children. However, the association’s nature remains elusive, i.e., why psychological stress predicts both decreased and increased physical activity. To test whether effects vary as a function of the level of analyses, we derived intensive longitudinal data via accelerometers and stress questionnaires from 74 children across 7 days as they went about their daily routines (n = 513 assessments). Multilevel modelling analyses revealed that between children, higher psychological stress predicted decreased physical activity (standardized beta coefficient = −0.14; p = 0.046). Concurrently, within those children, higher psychological stress predicted increased physical activity across days (standardized beta coefficient = 0.09; p = 0.015). Translated to practice, children who experienced more stress than others moved less, but children were more active on days when they experienced heightened stress. This suggests that the analyses level is crucial to the understanding of the association between psychological stress and physical activity and should be considered to receive unequivocal results. If replicated, e.g., including high-frequency sampling and experimental manipulation in everyday life for in-depth insights on underlying mechanisms and causality, our findings may be translated to individually tailored (digital) prevention and intervention strategies which target children’s distress-feelings despite impairing their heightened physical activity in stressful situations and identify tipping points of chronic stress phases. Therefore, we especially call for more intensive longitudinal data approaches to tackle thus far neglected within-subject issues in the field of physical activity, sport and exercise research.

A Better Cardiopulmonary Fitness Is Associated with Improved Concentration Level and Health-Related Quality of Life in Primary School Children

This study aimed to examine the physical fitness (PF) levels of primary school children and to determine the associations among PF, concentration, and health-related quality of life (HRQOL) in a subcohort. PF was assessed in 6533 healthy primary school-age children (aged 6−10 years, 3248 boys and 3285 girls) via standardized test batteries. Concentration was measured with the d2-R test, and KINDL questionnaires were used to determine HRQOL. Analysis of variance showed an increase in PF with age in all PF dimensions (all p < 0.001), except cardiopulmonary fitness (estimated VO2max) in girls (p = 0.129). Boys performed better in nearly all PF dimensions, except curl-ups, in all children aged ≥7 years (p < 0.05). Concentration levels increased in boys and girls aged 7−9 years (p < 0.001), whereas HRQOL did not (p = 0.179). The estimated VO2max had a strong impact on concentration (β = 0.16, p < 0.001) and HRQOL (β = 0.21, p < 0.001) in 9- to 10-year-olds. Cardiopulmonary fitness is important for improved concentration and better HRQOL in primary school-age children. However, longitudinal data are needed to provide further insight into the intraindividual relationships of PF and concentration over the course of child development and set up targeted prevention programs.

Muscular Fitness and Cardiometabolic Variables in Children and Adolescents: A Systematic Review

BACKGROUND

The importance of muscular fitness (MF) in the performance of activities of daily living is unequivocal. Additionally, emerging evidence has shown MF can reduce cardiometabolic risk in children and adolescents.

OBJECTIVES

The purpose of this study was to examine and summarize the evidence regarding the relationship between MF phenotypes (i.e., maximum muscular strength/power, muscular endurance, and maximum muscular strength/power/endurance) and cardiometabolic variables (obesity, blood pressure, lipids, glucose homeostasis, inflammatory markers, and clustered cardiometabolic variables) in children and adolescents.

DESIGN

This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and was registered with PROSPERO, number CRD42020179273.

DATA SOURCES

A systematic review was performed on five databases (PubMed, EMBASE, SciELO, Scopus, and Web of Knowledge) from database inception to May 2020, with complementary searches in reference lists.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Eligibility criteria included (1) a study sample of youth aged ≤ 19 years, (2) an assessment of MF with individual or clustered cardiometabolic variables derived from adjusted models (regardless of test/measurement adopted or direction of reported association), and (3) a report of the association between both, using observational studies. Only original articles published in peer-reviewed journals in English, Portuguese, and Spanish languages were considered. The quality of the included studies was assessed by using the National Heart, Lung, and Blood Institute checklist. The percentage of results reporting a statistically significant inverse association between each MF phenotype and cardiometabolic variables was calculated.

RESULTS

Of the 23,686 articles initially identified, 96 were included (77 cross-sectional and 19 longitudinal), with data from children and adolescents from 35 countries. The score for the quality of evidence ranged from 0.33 to 0.92 (1.00 maximum). MF assessed by maximum muscular strength/power was inversely associated with lower obesity (64/113 total results (56.6%)) and reduction in clustered cardiometabolic risk (28/48 total results (58.3%)). When assessed by muscular endurance, an inverse association with obesity (30/44 total results (68.1%)) and cardiometabolic risk (5/8 total results (62.5%)) was identified. Most of the results for the relationship between MF phenotypes with blood pressure, lipids, glucose homeostasis, and inflammatory markers indicated a paucity of evidence for these interrelationships (percentage of results below 50.0%).

CONCLUSION

MF assessed by maximum muscular strength/power or muscular endurance is potentially associated with lower obesity and lower risk related to clustered cardiometabolic variables in children and adolescents. There is limited support for an inverse association between MF with blood pressure, lipids, glucose homeostasis biomarkers, and inflammatory markers in children and adolescents.

Physical fitness of Latin America children and adolescents: a protocol for a systematic review and meta-analysis

INTRODUCTION

Physical fitness (PF) is an important indicator of health in children and adolescents. Internationally, test batteries have been used to assess overall PF. In Latin America, however, while PF has been widely measured, there is no accepted test battery, making it difficult to monitor and/or compare the PF levels of Latin children. The aim of this study, therefore, is to systematically review and potentially meta-analyse the peer-reviewed literature regarding the assessment of PF in Latin American children and adolescents.

METHODS AND ANALYSIS

This systematic review and meta-analysis will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols statement. The systematic literature search will be performed in MEDLINE, Scopus, SciELO, EMBASE, Cochrane Library, Web of Science, SPORTDiscus, LILACS and Latindex (Spanish) to locate articles published up to April 2021. Eligible studies will include both descriptive and analytic study designs. Meta-analyses are planned for sufficiently homogeneous PF outcomes with regard to statistical and methodological characteristics. Narrative syntheses are planned for PF outcomes that are considered to be too heterogeneous. The statistical program STATA V.15 will be used for meta-analyses, with subgroup analyses performed according to the characteristics of included studies.

ETHICS AND DISSEMINATION

This systematic review and meta-analysis protocol is designed to provide updated evidence on the PF of Latin American children and adolescents. Findings from this review may be useful for teachers, researchers and other professionals responsible for paediatric fitness and health promotion/surveillance. The results will be disseminated through peer-reviewed scientific publications, conferences, educational talks and infographics.

PROSPERO REGISTRATION NUMBER

CRD42020189892.

The Prevalence of Metabolic Syndrome According to Grip Strength in Teenagers

The prevalence of metabolic syndrome in adolescents is increasing. Recently, the relevance of grip strength as a factor of metabolic syndrome in this population has raised questions. This study investigated the prevalence of metabolic syndrome according to grip strength in children and adolescents using large-scale data from the Korean National Health and Nutrition Survey (KNHNS). From 2014 to 2018, 1527 boys and 1292 girls participated in the KNHNS. The participants were classified into three groups according to age: 10-12 years (early teenager, ET), 13-15 years (middle teenager, MT), and 16-18 years (late teenager, LT). The participants were classified as having metabolic syndrome if they fulfilled three of the adolescent metabolic syndrome criteria. The grip strength was divided into groups with high and low grip strength, respectively, and the cutoff value for the prevalence was calculated using receiver operating characteristic curve analysis. There were significant differences in waist circumference, high-density lipoprotein cholesterol, and triglyceride levels based on grip strength in the ET, MT, and LT groups. Therefore, the prevalence of metabolic syndrome was lower when grip strength was higher. The cut-off values of the relative grip strength (kg/body weight) to predict metabolic syndrome among boys were 0.349, 0.466, and 0.485 for the ET, MT, and LT groups, respectively. The corresponding cut-off values for girls were 0.373, 0.383, and 0.382, respectively. In conclusion, there is a non-linear relationship between grip strength and metabolic syndrome in adolescents.

Association between handgrip strength and cardiovascular risk factors among Korean adolescents

Background It remains unclear whether muscle strength, which reduces cardiovascular (CV) risk in adults, is associated with similar protection in Asian adolescents. This study investigated the association between handgrip strength and CV health in a large Korean sample of school-age adolescents. Methods We performed a cross-sectional analysis of adolescents aged 10-18 years (n=4,018) from the Korean National Health and Nutrition Survey between 2014 and 2017. Handgrip strength was measured using a dynamometer. CV risk factors include waist circumference, blood pressure, fasting glucose or hemoglobin A1c, and lipid levels. Logistic regression models were applied with adjustment for potential confounders. Results The mean age of participants was 14.0 years, and 53.6% were boys. Mean handgrip strength was 30.4 kg for boys and 22.0 kg for girls. Boys more frequently had high systolic blood pressure and impaired fasting glucose, whereas girls more frequently had low high-density lipoprotein cholesterol. Multivariate logistic regression analysis revealed that in boys only, handgrip strength was negatively associated with central obesity and hypertriglyceridemia and positively associated with higher systolic blood pressure. Conclusion Handgrip strength is independently associated with some CV risk factors only in boys.

Growing up strong: The importance of physical, mental, and emotional strength during childhood and adolescence with focus on dietary factors

Childhood and adolescence are critical time periods for growth and development. Given the current physical and psychological health concerns affecting United States youth, an emerging area of interest exists supporting the importance of physical and psychological aspects of strength for health, resilience, and well-being through these life stages. This synopsis highlights the key concepts that were presented within the 2018 Strength Summit conference, entitled The Role of Strength in Optimal Health and Well-being. During the conference, strength was broadly defined as the ability to successfully respond to a challenge. Although much of the current research focuses on strength from a muscle function and performance perspective, mental and emotional strength are also important components of overall health and well-being, especially in children and adolescents. This paper provides a brief overview of the clinical and/or research-based strength outcomes, summarizes the relationship between strength and health, and discusses evidence-based dietary factors that promote strength in children and adolescents. Novelty Building physical, mental, and emotional strength during childhood and adolescence lays the foundation for health and well-being. Emerging evidence indicate positive associations between diet quality and strength in children and adolescents. Promising areas include the promotion of family-based meals, with focus on breakfast, for improved strength in United States youth.

Reference Values for Fitness Level and Gross Motor Skills of 4-6-Year-Old Chilean Children

In childhood, fitness level is considered an important indicator of health, while gross motor skills are the basis of future motor competence. So far, no reference values have been found for the Chilean population. Therefore, this study aims to provide fitness level and gross motor skill reference values by gender and age of Chilean children aged 4–6 years. A cross-sectional analysis was conducted that included 728 children between 4 and 6 years old from the La Araucanía region of Chile. To assess the fitness level, the 20-m shuttle run test, standing long jump, handgrip dynamometry, 4x10m shuttle run, and Sit and Reach tests were used. Gross motor skills were assessed by five tests including aiming and catching and balance motor tasks. For fitness level, boys have better values in the long jump and dynamometry test, while girls have better values in flexibility. For estimated maximum volume of oxygen, at 5 years old there are significant differences in favour of boys, while at 6 years old in favour of girls. No statistically significant differences in speed/agility by gender were found. For gross motor skills, boys obtain higher values for catching and aiming tests, and girls for balance. The reference values for fitness level and gross motor skills shown in this study could aid physical education and health professionals in identifying children with low reference values, as well as in establishing objectives that will help to improve their health.

Sibling Similarity in Metabolic Syndrome: The Portuguese Sibling Study on Growth, Fitness, Lifestyle and Health

This study aims to estimate sibling resemblance in metabolic syndrome (MS) markers, and to investigate the associations of biological and behavioral characteristics with MS. The sample comprises 679 biological siblings (363 females; 316 males) aged 9-20 years. MS markers included waist circumference (WC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TRI), fasting glucose (GLU) and systolic blood pressure (SBP). Body mass index (BMI), biological maturation, muscular, and cardiorespiratory fitness were also assessed. Behavioral characteristics, including dietary intake and physical activity, were self-reported by questionnaire. Multilevel models were used, and sibling resemblance was estimated using the intraclass correlation (ρ). In general, same-sex siblings showed higher resemblance in MS markers than opposite-sex siblings. However, variability in sibling resemblance in MS markers was evident with the inclusion of covariates. Biological characteristics including age, BMI and maturity offset influenced all MS markers except for TRI. Importantly, behavioral characteristics diversely influenced MS markers: fruit and vegetables only influenced SBP, whereas physical activity affected HDL-C. Additionally, muscular fitness impacted significantly on MS Z-score, WC, SBP and GLU, whilst cardiorespiratory fitness only affected WC. In conclusion, biological and behavioral characteristics influenced the expression of MS markers. These results confirmed the importance of considering individual characteristics when designing individualized programs for diminishing the adverse effects of specific MS markers.

Expert's Choice: 2018's Most Exciting Research in the Field of Pediatric Exercise Science

This commentary highlights 23 noteworthy publications from 2018, selected by leading scientists in pediatric exercise science. These publications have been deemed as significant or exciting in the field as they (a) reveal a new mechanism, (b) highlight a new measurement tool, (c) discuss a new concept or interpretation/application of an existing concept, or (d) describe a new therapeutic approach or clinical tool in youth. In some cases, findings in adults are highlighted, as they may have important implications in youth. The selected publications span the field of pediatric exercise science, specifically focusing on: aerobic exercise and training; neuromuscular physiology, exercise, and training; endocrinology and exercise; resistance training; physical activity and bone strength; growth, maturation, and exercise; physical activity and cognition; childhood obesity, physical activity, and exercise; pulmonary physiology or diseases, exercise, and training; immunology and exercise; cardiovascular physiology and disease; and physical activity, inactivity, and health.

Movement behaviors and cardiometabolic risk in schoolchildren

Growing evidence has accumulated in recent years showing that movement behaviors have important implications for health in children, especially for cardiovascular health, whose risk factors could track from childhood to adulthood. However, these findings are mixed and inconsistent in children. The aim of this study was to examine the relationship between different movement behaviors (sedentary behavior, physical activity and sleep duration) and cardiometabolic risk in schoolchildren. The study shows cross-sectional results of baseline measurement from 146 Spanish schoolchildren, aged 8-to-11 years old, participating in the MOVI-2 study. Movement behaviors were determined using accelerometry combined with self-reported sleep time. Cardiometabolic risk was assessed using a validated metabolic syndrome index. Logistic regression analysis showed that higher levels of vigorous physical activity (OR = 0.110, p = 0.004) and sleeping more than 9 hours (OR = 0.269, p = 0.015) could be protective factors against metabolic syndrome risk in children. ANCOVA analysis showed associations between vigorous physical activity and waist circumference (p < 0.001), and sleep time with insulin resistance (p = 0.017) and lipid profile (p = 0.035). No association was observed between light and moderate physical activity, sedentary behavior and metabolic syndrome (index and components). No statistically significant differences were found for blood pressure and any of the movement behaviors. Our data suggest that both the amount of vigorous physical activity accumulated and sleep duration are independently associated with higher cardiometabolic risk in children.

Longitudinal associations of physical activity and sedentary time with cardiometabolic risk factors in children

BACKGROUND

There are few prospective studies on the associations of changes in objectively measured vigorous physical activity (VPA_∆ ), moderate-to-vigorous physical activity (MVPA_∆ ), light physical activity (LPA_∆ ), and sedentary time (ST_∆ ) with changes in cardiometabolic risk factors (_∆ ) in children. We therefore investigated these relationships among children.

METHODS

The participants were a population sample of 258 children aged 6-8 years followed for 2 years. We assessed PA and ST by a combined heart rate and movement sensor; computed continuous age- and sex-adjusted z-scores for waist circumference, blood pressure, and fasting insulin, glucose, triglycerides, and high-density lipoprotein (HDL) cholesterol; and constructed a cardiometabolic risk score (CRS) of these risk factors. Data were analyzed using linear regression models adjusted for age, sex, the explanatory and outcome variables at baseline, and puberty.

RESULTS

VPA_∆ associated inversely with CRS_∆ (β = -0.209, P = 0.001), body fat percentage (BF%)_∆ (β = -0.244, P = 0.001), insulin_∆ (β = -0.220, P = 0.001), and triglycerides_∆ (β = -0.164, P = 0.012) and directly with HDL cholesterol_∆ (β = 0.159, P = 0.023). MVPA_∆ associated inversely with CRS_∆ (β = -0.178, P = 0.012), BF%_∆ (β = -0.298, P = <0.001), and insulin_∆ (β = -0.213, P = 0.006) and directly with HDL cholesterol_∆ (β = 0.184, P = 0.022). LPA_∆ only associated negatively with CRS_∆ (β = -0.163, P = 0.032). ST_∆ associated directly with CRS_∆ (β = 0.218, P = 0.003), BF%_∆ (β = 0.212, P = 0.016), and insulin_∆ (β = 0.159, P = 0.049).

CONCLUSIONS

Increased VPA and MVPA and decreased ST were associated with reduced overall cardiometabolic risk and major individual risk factors. Change in LPA had weaker associations with changes in these cardiometabolic risk factors. Our findings suggest that increasing at least moderate-intensity PA and decreasing ST decrease cardiometabolic risk in children.

Muscular Fitness and Cardiovascular Risk Factors in Children and Adolescents: A Systematic Review

Rodrigues de Lima, T, Custódio Martins, P, Henrique Guerra, P, and Augusto Santos Silva, D. Muscular fitness and cardiovascular risk factors in children and adolescents: A systematic review. J Strength Cond Res 34(8): 2394-2406, 2020-The purpose of this study was to identify and summarize the relationships between muscular fitness (MF) and individual components of metabolic syndrome (high waist circumference [WC], high blood pressure [BP], high systolic BP [SBP], high diastolic BP [DBP], high triglycerides [TG], fasting blood glucose [FG], and low HDL cholesterol levels [HDL-C]) in children and adolescents. A systematic review was conducted in 5 electronic databases, with complementary searches in reference lists, and the inclusion criteria were children and adolescents (age group up to 19 years of age) with no special clinical conditions. In all articles, risk of bias was analyzed by a standardized instrument. Of the 5,973 articles initially identified, 21 were included, with data on 22,261 children and adolescents. Higher MF values were associated with lower TG (n = 07) and WC values (n = 15). Different results in relation to the relationship between MF and SBP (n = 10) and MF and DBP (n = 07) were verified. In addition, there was no relationship between MF and FG (n = 06). In addition, inconclusive results were verified in the relationship between MF and HDL-C (n = 07). Concluded higher MF values were related to lower WC values and lower TG concentrations.