Low muscle strength is associated with metabolic risk factors in Colombian children: the ACFIES study

Negative associations between step-up height and waist circumference in 8-year-old children and their parents

AIM

To study cross-sectional relationships between step-up height and waist circumference (WC), a potential proxy for sarcopenic obesity, in Swedish children and parents.

METHODS

Participants were recruited from Swedish schools in disadvantaged areas in 2017. Height, body weight, WC and maximal step-up height were measured in 67 eight-year-old children and parents: 58 mothers, with a mean age of 38.5 and 32 fathers, with a mean age of 41.3. Sedentary time and physical activity were registered by an accelerometer. Associations between maximal step-up height and WC were analysed using Pearson's correlation and adjusted linear regression.

RESULTS

Abdominal obesity, WC ≥ 66 centimetres (cm) in children, ≥88 cm in women and ≥102 cm in men, was observed in 13% and 35% of girls and boys, and in 53% and 34% among mothers and fathers, respectively. Negative associations between maximal step-up height and WC were found for children (r = -0.37, p = 0.002) and adults (mothers r = -0.58, p < 0.001, fathers r = -0.48, p = 0.006). The associations remained after adjustments for height, body mass index (BMI) and physical activity in adults. Reduced muscle strength clustered within families (r = 0.54, p < 0.001).

CONCLUSION

Associations between reduced muscle strength and abdominal obesity were observed in children and parents. Sarcopenic obesity may need more attention in children. Our findings support family interventions.

The Effects of a Physical Activity Intervention on Adiposity, Physical Fitness and Motor Competence: A School-Based, Non-Randomized Controlled Trial

Evidence suggests that early physical activity interventions are a means of preventing childhood obesity and are more effective when delivered in a school setting and based on the ecological model. Therefore, the present study aims to determine the effect of a multicomponent intervention based on the ecological model on adiposity, physical fitness and motor competence in children aged 4 to 5 years.

METHODS

This study is a non-randomized controlled trial involving 173 children from Chile. The intervention was based on an ecological model and consisted of a physical activity program with three simultaneous parts, affecting intra- and interpersonal dimensions. The adiposity index, body mass index and waist circumference were measured. For physical fitness, muscle strength in the lower part, speed/agility and cardiorespiratory fitness were measured. Motor competence was assessed using catching, aiming and dynamic and static balance tests.

RESULTS

After the intervention, there was no reduction in adiposity indices; in the intervention group, body mass index increased significantly with a high effect size. The intervention group showed significant differences in physical fitness in the components of muscle strength in the lower part (p = 0.000) and speed/agility (p = 0.002). For motor competence, the intervention group showed significant improvements in most components.

CONCLUSIONS

The multicomponent intervention did not reduce adiposity indices; however, it caused significant improvements in the physical fitness and motor competence components, so it seems prudent to continue implementing it, given the benefits that adequate levels of motor competence and physical fitness bring to children's health, both in the short and long term.

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.

Cardiometabolic risk factors in South American children: A systematic review and meta-analysis

BACKGROUND

Cardiometabolic risk factors (impaired fasting glucose, abdominal obesity, high blood pressure, dyslipidemia) cluster in children, may predict adult disease burden, and are inadequately characterized in South American children.

OBJECTIVES

To quantify the burden of cardiometabolic risk factors in South American children (0-21 years) and identify knowledge gaps.

METHODS

We systematically searched PubMed, Google Scholar, and the Latin American and Caribbean Health Sciences Literature via Virtual Health Library from 2000-2021 in any language. Two independent reviewers screened and extracted all data.

RESULTS

179 studies of 2,181 screened were included representing 10 countries (n = 2,975,261). 12.2% of South American children experienced obesity, 21.9% elevated waist circumference, 3.0% elevated fasting glucose, 18.1% high triglycerides, 29.6% low HDL cholesterol, and 8.6% high blood pressure. Cardiometabolic risk factor definitions varied widely. Chile exhibited the highest prevalence of obesity/overweight, low HDL, and impaired fasting glucose. Ecuador exhibited the highest prevalence of elevated blood pressure. Rural setting (vs. urban or mixed) and indigenous origin protected against most cardiometabolic risk factors.

CONCLUSIONS

South American children experience high rates of obesity, overweight, and dyslipidemia. International consensus on cardiometabolic risk factor definitions for children will lead to improved diagnosis of cardiometabolic risk factors in this population, and future research should ensure inclusion of unreported countries and increased representation of indigenous populations.

Handgrip Strength Is Associated with Specific Aspects of Vascular Function in Individuals with Metabolic Syndrome

BACKGROUND

Metabolic syndrome (MetS) is a disorder associated with an increased risk for the development of diabetes mellitus and its complications. Lower isometric handgrip strength (HGS) is associated with an increased risk of cardiometabolic diseases. However, the association between HGS and arterial stiffness parameters, which are considered the predictors of morbidity and mortality in individuals with MetS, is not well defined.

OBJECTIVE

To determine the association between HGS and HGS asymmetry on components of vascular function in adults with MetS.

METHODS

We measured handgrip strength normalized to bodyweight (HGS/kg), HGS asymmetry, body composition, blood glucose, lipid profile, blood pressure, pulse wave velocity (PWV), reflection coefficient (RC), augmentation index @75 bpm (AIx@75) and peripheral vascular resistance (PVR) in 55 adults with a diagnosis of MetS between 25 and 54 years old.

RESULTS

Mean age was 43.1 ± 7.0 years, 56.3% were females. HGS/kg was negatively correlated with AIx@75 (r = -0.440), p < 0.05, but these associations were not significant after adjusting for age and sex. However, when interaction effects between sex, HGS/kg and age were examined, we observed an inverse relationship between HGS/kg and AIx@75 in the older adults in the sample, whereas in the younger adults, a weak direct association was found. We also found a significant association between HGS asymmetry and PVR (beta = 30, 95% CI = 7.02; 54.2; p <0.012).

CONCLUSIONS

Our findings suggest that in people with MetS, maintaining muscle strength may have an increasingly important role in older age in the attenuation of age-related increases in AIx@75-a marker of vascular stiffness-and that a higher HGS asymmetry could be associated with a greater vascular resistance.

Obesity Status and Physical Fitness Levels in Male and Female Portuguese Adolescents: A Two-Way Multivariate Analysis

Obesity and decreasing fitness levels among the youth are growing concerns in Portugal, similar to other developed countries, with implications for health and psychomotor development. Understanding the influence of health determinants such as sex and age are crucial for developing effective public health strategies. This study aimed to analyze the association between sex and chronological age with obesity status and physical fitness in Portuguese adolescents. A total of 170 adolescents (85 males and 85 females) were evaluated for body mass index, abdominal adiposity, aerobic fitness, abdominal resistance, upper limb resistance, lower limb power, and maximal running speed in a 40 m sprint using the FITescola^® physical fitness battery, a Portuguese government initiative. The general model, analyzed using Pillai's trace, showed a significant effect of age and sex on body mass index, abdominal circumference, aerobic fitness, abdominal resistance, upper limb resistance, lower limb power, and maximal running speed (V = 0.99, F (7) = 10,916.4, p < 0.001, partial η2, sex = 0.22; age = 0.43, sex and age interaction = 0.10). Boys had higher physical fitness levels than girls in most tests, but both sex groups had a significantly higher proportion of non-fit adolescents, with boys showing the highest number of participants classified as non-fit.

Epidemiological, mechanistic, and practical bases for assessment of cardiorespiratory fitness and muscle status in adults in healthcare settings

Given their importance in predicting clinical outcomes, cardiorespiratory fitness (CRF) and muscle status can be considered new vital signs. However, they are not routinely evaluated in healthcare settings. Here, we present a comprehensive review of the epidemiological, mechanistic, and practical bases of the evaluation of CRF and muscle status in adults in primary healthcare settings. We highlight the importance of CRF and muscle status as predictors of morbidity and mortality, focusing on their association with cardiovascular and metabolic outcomes. Notably, adults in the best quartile of CRF and muscle status have as low as one-fourth the risk of developing some of the most common chronic metabolic and cardiovascular diseases than those in the poorest quartile. The physiological mechanisms that underlie these epidemiological associations are addressed. These mechanisms include the fact that both CRF and muscle status reflect an integrative response to the body function. Indeed, muscle plays an active role in the development of many diseases by regulating the body's metabolic rate and releasing myokines, which modulate metabolic and cardiovascular functions. We also go over the most relevant techniques for assessing peak oxygen uptake as a surrogate of CRF and muscle strength, mass, and quality as surrogates of muscle status in adults. Finally, a clinical case of a middle-aged adult is discussed to integrate and summarize the practical aspects of the information presented throughout. Their clinical importance, the ease with which we can assess CRF and muscle status using affordable techniques, and the availability of reference values, justify their routine evaluation in adults across primary healthcare settings.

Fitness, body composition, and metabolic risk scores in children and adolescents: the UP&DOWN study

We aimed to analyse the longitudinal association between physical fitness (PF) and body composition (BC) with a metabolic risk score (Met4) in children and adolescents and to elucidate whether the association between PF and Met4 differs when using relativized or absolute fitness variables. A total of 188 children (86 females) and 195 adolescents (97 females) were included. Cardiorespiratory fitness (CRF) was determined by the 20-m shuttle run test, and muscular fitness (MF) was determined by hand grip and standing long jump tests. Height and weight were measured, and the body mass index (Kg/m²) was calculated. Triceps and subscapular skinfolds were assessed to compute body fat percentage. Met4 was computed from systolic blood pressure, triglycerides, high-density lipoprotein cholesterol, and glucose levels. Relative CRF was longitudinally and negatively associated with Met4 in female children (β =  -0.031, p = 0.025), while absolute CRF was positively associated with Met4 in male children and adolescents (β = 0.000, p < 0.05). Relative upper and lower-body MF were longitudinally and negatively associated with Met4 in female adolescents (β =  -1.347, β =  -0.005, p < 0.05), while absolute lower-body MF was positively associated with Met4 in male children (β = 0.000, p = 0.019). BC was longitudinally and positively associated with Met4 in male children (β-ranging from 0.011 to 0.055, all p < 0.05) and male adolescents (β-ranging from 0.011 to 0.046, all p < 0.05).  Conclusion: BC is more strongly associated with Met4 than PF in children and adolescents. An optimal body weight status should be considered the main objective of health-promoting programs at childhood and adolescence. Furthermore, the way of expressing the fitness variables determines the direction of the association with Met4. What is Known: • Physical fitness is an important health indicator in children and adolescents, with great amount of previous evidence supporting the preventive role of maintaining optimal levels of both cardiorespiratory and muscular fitness for future cardiometabolic issues. What is New: • The way of reporting physical fitness variables can affect the associations between physical fitness features and cardiometabolic outcomes. Since body composition variables have a great impact on both physical fitness and cardiometabolic health, relativizing physical fitness performance by body composition could lead to erroneous conclusions.

Fat-free mass and maturity status are determinants of physical fitness performance in schoolchildren and adolescents

OBJECTIVES

The objective of the study was to verify whether (FFM), maturity status (MS) and chronological age (CA) are determinants of physical fitness performance, and to analyze FFM and physical performance aligned by CA and MS in children and adolescents.

METHODS

A descriptive correlational study was carried out in 863 schoolchildren. Weight, height, and waist circumference (WC) were evaluated. Body mass index (BMI), FFM, fat mass (FM), MS (Age at peak height velocity, APHV) were calculated. The physical tests of velocity 20 m, agility 5 m x 10rep, and horizontal jump (HJ) were evaluated.

RESULTS

The APHV was estimated in boys at 14.0 ± 0.36APHV and in girls at 11.96 ± 0.49APHV. The relationships between CA and APHV with FFM was r = 0.80 in boys and r = 0.44 to 0.45 in girls. The relationships between FFM and physical tests in boys were [HJ (r = 0.70), agility 5m x 10rep (r = -0.68), velocity (r = -0.61)] and in girls [HJ (r = 0.42), agility 5m x 10rep (r = -0.52), velocity (r = -0.20)]. The differences in FFM and physical fitness tests were more pronounced when aligned by APHV than by CA.

CONCLUSION

It was verified that both FFM, CA, and APHV are determinants of physical fitness performance. In addition, the APHV should be introduced in physical education as a means of ranking physical performance among schoolchildren.

Handgrip Strength Is Associated with Metabolic Syndrome and Insulin Resistance in Children and Adolescents: Analysis of Korea National Health and Nutrition Examination Survey 2014-2018

Background

Reduced handgrip strength (HGS) is associated with adverse cardiometabolic health outcomes. We examined HGS, metabolic syndrome (MetS), and insulin resistance (IR) in children and adolescents.

Methods

The following population-based data from 2,797 participants (aged 10-18 years) of the Korea National Health and Nutrition Examination Survey 2014-2018 were analyzed: complete anthropometric measures, HGS, MetS, and IR (subgroup with fasting insulin, n=555). HGS was analyzed as the combined HGS (CHGS) and the normalized CHGS (nCHGS=CHGS divided by body weight).

Results

At a mean age of 14.4 years, 276 participants (9.9%) had abdominal obesity, 56 (2.0%) had MetS, and 118 (20.9%) had IR. Individual components of MetS and IR were inversely associated with the nCHGS. The odds ratios (ORs) for MetS and IR decreased significantly with higher nCHGS after adjustment for sex, age, physical activity, and sedentary times. The optimal cut-off values that predicted MetS were 0.80 kg/kg (males) and 0.71 kg/kg (females), with significant associations with MetS (OR: 7.4 in males; 5.7 in females) and IR (OR: 3.3 in males; 3.2 in females) observed when nCHGS values were lower than those cut-offs.

Conclusion

HGS is associated with MetS and IR and might be a useful indicator of cardiometabolic risk factors in children and adolescents.

Probabilistic prediction of segmental body composition in Iranian children and adolescents

Background

Adolescents' body composition is considered an important measure to evaluate health status. An examination of any of the segmental compartments by anthropometric indices is a more usable method than direct methods.

Objectives

To propose a method based on the network approach for predicting segmental body composition components in adolescent boys and girls using anthropometric measurements.

Methods

A dual-energy X-ray absorptiometry (DXA) dataset in the south of Iran, including 476 adolescents (235 girls and 241 boys) with a range of 9–18 years, was obtained. Several anthropometric prediction models based on the network approach were fitted to the training dataset (TRD 80%) using bnlearn, an R add-in package. The best fitted models were applied to the validation dataset (VAD 20%) to assess the prediction accuracy.

Results

Present equations consisting of age, weight, height, body mass index (BMI), and hip circumference accounted for 0.85 (P < 0.001) of the variability of DXA values in the corresponding age groups of boys. Similarly, reasonable estimates of DXA values could be obtained from age, weight, height, and BMI in girls over 13 years, and from age, weight, height, BMI, and waist circumference in girls under 13 years, respectively, of 0.77 and 0.83 (P < 0.001). Correlations between robust Gaussian Bayesian network (RGBN) predictions and DXA measurements were highly significant, averaging 0.87 for boys and 0.82 for girls (P < 0.001).

Conclusions

The results revealed that, based on the present study’s predictive models, adolescents' body composition might be estimated by input anthropometric information. Given the flexibility and modeling of the present method to test different motivated hypotheses, its application to body compositional data is highly appealing.

Muscle-strengthening exercise and positive mental health in children and adolescents: An urban survey study

Background

Much evidence has indicated that physical activity is associated with mental health benefits, such as fewer depression symptoms. Psychological resilience captures a broader mental health phenomenon that may be influenced by other factors as well. Yet, there are few studies examining the association between muscle-strengthening exercises (MSEs) with mental health outcomes, especially positive outcomes (e.g., subjective wellbeing). The study aimed to test the association between MSE with subjective wellbeing and resilience among a large sample of Chinese adolescents.

Materials and methods

A cross-sectional study was conducted among primary and middle school students in Shenzhen, China. MSE frequency, subjective wellbeing, and resilience were measured. Data from a total of 67,281 children and adolescents aged 10–17 years (51.9% men and 48.1% women) were included in the analysis. Mixed effect models were performed to assess how weekly MSE frequency (0–7 days) related to the levels of subjective wellbeing and resilience, adjusting for potential confounding variables (e.g., sex and grade). Sensitivity analyses were also conducted.

Results

Compared to participants with no MSE, the levels of subjective wellbeing were higher in those with higher MSE frequencies [range of β: 0.29 (1 day per week) to 1.98 (7 days per week)]. The frequency of MSE was also positively correlated to better resilience [range of β: 0.50 (1 day per week) to 4.40 (7 days per week)]. All associations remained significant in sensitivity analyses.

Conclusion

More frequent MSE was associated with superior subjective wellbeing and resilience of Chinese children and adolescents. Increasing MSE may be beneficial for promoting positive mental health outcomes among children and adolescents.

Normalized sensitivity of multi-dimensional body composition biomarkers for risk change prediction

The limitations of BMI as a measure of adiposity and health risks have prompted the introduction of many alternative biomarkers. However, ranking diverse biomarkers from best to worse remains challenging. This study aimed to address this issue by introducing three new approaches: (1) a calculus-derived, normalized sensitivity score (NORSE) is used to compare the predictive power of diverse adiposity biomarkers; (2) multiple biomarkers are combined into multi-dimensional models, for increased sensitivity and risk discrimination; and (3) new visualizations are introduced that convey complex statistical trends in a compact and intuitive manner. Our approach was evaluated on 23 popular biomarkers and 6 common medical conditions using a large database (National Health and Nutrition Survey, NHANES, N ~ 100,000). Our analysis established novel findings: (1) regional composition biomarkers were more predictive of risk than global ones; (2) fat-derived biomarkers had stronger predictive power than weight-related ones; (3) waist and hip are always elements of the strongest risk predictors; (4) our new, multi-dimensional biomarker models yield higher sensitivity, personalization, and separation of the negative effects of fat from the positive effects of lean mass. Our approach provides a new way to evaluate adiposity biomarkers, brings forth new important clinical insights and sets a path for future biomarker research.

Is grip strength linked to body composition and cardiovascular risk markers in primary schoolchildren? Cross-sectional data from three African countries

OBJECTIVES

Muscular strength represents a specific component of health-related fitness. Hand grip strength (HGS) is used as an indicator for musculoskeletal fitness in children. HGS can also be used as a marker of cardiometabolic risk, but most available HGS data are derived from Western high-income countries. Therefore, this study examines whether HGS is associated with body composition and markers of cardiovascular risk in children from three sub-Saharan African countries.

DESIGN

Cross-sectional study.

SETTING

Public primary schools (grade 1-4) in Taabo (Côte d'Ivoire), Gqeberha (South Africa) and Ifakara (Tanzania).

PARTICIPANTS

Data from 467 children from Côte d'Ivoire (210 boys, 257 girls), 864 children from South Africa (429 boys, 435 girls) and 695 children from Tanzania (334 boys, 361 girls) were analysed.

PRIMARY AND SECONDARY OUTCOME MEASURES

Body composition (assessed via bioelectrical impedance analysis) was the primary outcome. Cardiovascular risk markers were considered as secondary outcome. Blood pressure was measured with an oscillometric monitor, and blood markers (cholesterol, triglycerides, glycated haemoglobin) via Afinion point-of-care testing. HGS (independent variable) was assessed with a hydraulic hand dynamometer. Inferential statistics are based on mixed linear regressions and analyses of covariance.

RESULTS

Across all study sites, higher HGS was associated with lower body fat, higher muscle mass and higher fat-free mass (p<0.001, 3.9%-10.0% explained variance), both in boys and girls. No consistent association was found between HGS and cardiovascular risk markers.

CONCLUSIONS

HGS assessment is popular due to its simplicity, feasibility, practical utility and high reliability of measurements. This is one of the first HGS studies with children from sub-Saharan Africa. There is a great need for further studies to examine whether our findings can be replicated, to develop reference values for African children, to establish links to other health outcomes, and to explore whether HGS is associated with later development of cardiovascular risk markers.

TRIAL REGISTRATION NUMBER

ISRCTN29534081.

Association of plasma kynurenine pathway metabolite concentrations with metabolic health risk in prepubertal Asian children

BACKGROUND

The tryptophan-kynurenine (KYN) pathway is linked to obesity-related systemic inflammation and metabolic health. The pathway generates multiple metabolites, with little available data on their relationships to early markers of increased metabolic disease risk in children. The aim of this study was to examine the association of multiple KYN pathway metabolites with metabolic risk markers in prepubertal Asian children.

METHODS

Fasting plasma concentrations of KYN pathway metabolites were measured using liquid chromatography-tandem mass spectrometry in 8-year-old children (n = 552) from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) prospective mother-offspring cohort study. The child's weight and height were used to ascertain overweight and obesity using local body mass index (BMI)-for-age percentile charts. Body fat percentage was measured by quantitative magnetic resonance. Abdominal circumference, systolic and diastolic blood pressure, homeostatic model assessment for insulin resistance (HOMA-IR), triglyceride, and HDL-cholesterol were used for the calculation of Metabolic syndrome scores (MetS). Serum triglyceride, BMI, gamma-glutamyl transferase (GGT), and abdominal circumference were used in the calculation of the Fatty liver index (FLI). Associations were examined using multivariable regression analyses.

RESULTS

In overweight or obese children (n = 93; 16.9% of the cohort), all KYN pathway metabolites were significantly increased, relative to normal weight children. KYN, kynurenic acid (KA), xanthurenic acid (XA), hydroxyanthranilic acid (HAA) and quinolinic acid (QA) all showed significant positive associations with body fat percentage (B(95% CI) = 0.32 (0.22,0.42) for QA), HOMA-IR (B(95% CI) = 0.25 (0.16,0.34) for QA), and systolic blood pressure (B(95% CI) = 0.14(0.06,0.22) for QA). All KYN metabolites except 3-hydroxykynurenine (HK) significantly correlated with MetS (B (95% CI) = 0.29 (0.21,0.37) for QA), and FLI (B (95% CI) = 0.30 (0.21,0.39) for QA).

CONCLUSIONS

Higher plasma concentrations of KYN pathway metabolites are associated with obesity and with increased risk for metabolic syndrome and fatty liver in prepubertal Asian children.

Fitness Changes in Adolescent Girls Following In-School Combined Aerobic and Resistance Exercise: Interaction With Birthweight

PURPOSE

To assess the efficacy of a supervised in-school combined resistance and aerobic training program in adolescent girls and investigate whether responses differ according to birthweight.

METHODS

Participants (girls aged 13-17 y) were randomized either to an intervention replacing physical education (PE) classes with 2 × 60-minute training sessions per week (n = 58) or to a control group that continued to attend 2 × 60 minutes per week of curriculum PE (n = 41). We measured muscular fitness (handgrip, standing long jump, and sit-ups), cardiorespiratory fitness (20-m shuttle run), skinfolds, and lean body mass preintervention and postintervention and determined effect size (Hedge's g) differences between changes in these measures. We also compared changes within lower (<3000 g) and normal birthweight intervention and PE control subgroups.

RESULTS

The intervention group showed greater improvements in all the fitness measures and lean body mass (g = 0.22-0.48) and lower skinfold increases (g = 0.41) than PE controls. Within the intervention group, improvements in all fitness measures were larger in lower birthweight (g = 0.53-0.94) than in normal birthweight girls (g = 0.02-0.39).

CONCLUSION

Replacing curriculum PE with supervised training improved muscular and cardiorespiratory fitness and body composition outcomes in adolescent females. Our findings suggest an enhanced adaptive response to training in participants with lower birthweight which warrants further investigation.

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.

Acute effect of a static- and dynamic-based stretching warm-up on standing long jump performance in primary schoolchildren

The aim of the present study was to compare the acute effect of a static- vs dynamic-based stretching warm-up on standing long jump (SLJ) performance in primary schoolchildren. The sample was composed of 76 schoolchildren, 43 girls and 33 boys, aged 9–10 years old from three fourth-grade classes of Primary Education. The three groups were cluster-randomly assigned to the control (CG), static (SG) or dynamic (DG) groups. All the schoolchildren performed a standardized warm-up consisting of mobility exercises (five minutes), jogging (five minutes) and the SLJ test. Afterwards the CG schoolchildren received jump theory (eight minutes), the SG performed static stretching (eight minutes) and the DG performed dynamic-bounces stretching (eight minutes). Afterwards, all of them performed the SLJ test again. The results of the one-way ANOVA (F_2,73 = 34.184; p < 0.001; η²p = 0.484), followed by the pairwise comparisons with the Bonferroni adjustment, showed that the DG students (M_Δ = 11.07, SE = 1.42) made a significant statistical improvement in their SJL levels compared with the CG (M_Δ = -3.00, SE = 1.89; p < 0.001, d = 1.51) and SG students (M_Δ = -1.85, SE = 0.67; p < 0.001, d = 1.38). However, statistically significant differences between the CG and SG students were not found (p > 0.05, d = 0.12). The dynamic-bouncing stretch as a final part of a warm-up improves explosive strength performance in primary schoolchildren, and seems to be a good option before carrying out explosive strength activities of the lower body.

Normalization of Muscle Strength Measurements in the Assessment of Cardiometabolic Risk Factors in Adolescents

Muscle strength (MS) has been associated with cardiometabolic risk factors (CMR) in adolescents, however, the impact attributed to body size in determining muscle strength or whether body size acts as a confounder in this relationship remains controversial. We investigated the association between absolute MS and MS normalized for body size with CMR in adolescents. This was a cross-sectional study comprising 351 adolescents (44.4% male; 16.6 ± 1.0 years) from Brazil. MS was assessed by handgrip and normalized for body weight, body mass index (BMI), height, and fat mass. CMR included obesity, high blood pressure, dyslipidemia, glucose imbalance, and high inflammation marker. When normalized for body weight, BMI, and fat mass, MS was inversely associated with the presence of two or more CMR among females. Absolute MS and MS normalized for height was directly associated with the presence of two or more CMR among males. This study suggests that MS normalized for body weight, BMI, and fat mass can be superior to absolute MS and MS normalized for height in representing lower CMR among females. Absolute MS and MS normalized for height were related to higher CMR among males.

Using relative handgrip strength to identify children at risk of sarcopenic obesity

Introduction

Background: identifying children at risk of developing childhood sarcopenic obesity often requires specialized equipment and expensive testing procedures, so cheaper and quicker methods would be advantageous, especially in field-based settings. Objective: the purpose of this study was to determine the relationships between the muscle-to-fat ratio (MFR) and relative handgrip strength, and to determine the ability of handgrip strength relative to body mass index (grip-to-BMI) to identify children who are at risk of developing sarcopenic obesity. Material and method: grip-to-BMI was measured in 4021 Macedonian children (6 to 10 yrs). Bioelectrical impedance was used to estimate body fat mass and skeletal muscle mass, from which the MFR was calculated. Results: the area under the curve (AUC) was 0.771 (95 % CI, 0.752 to 0.789, p < 0.001) in girls 6-10 years old and 0.843 (95 % CI, 0.826 to 0.859, p < 0.001) in boys 6-10 years old. Calculated using the grip-to-BMI ratio, the OR (95 % CI) for girls to be at risk of sarcopenic obesity identified by MFR was 20.182 (10.728-37.966, p < 0.001) and was 16.863 (10.782-26.371, p < 0.001) for boys. Conclusion: the grip-to-BMI ratio can be used to predict the presence of sarcopenic obesity in children, which can play a role in pediatric health interventions.

The SIMAC study: A randomized controlled trial to compare the effects of resistance training and aerobic training on the fitness and body composition of Colombian adolescents

The aim of this study was to evaluate the impact on muscle strength, aerobic fitness and body composition, of replacing the physical education (PE) class of Colombian adolescents with resistance or aerobic training. 120 tanner stage 3 adolescents attending a state school were randomized to resistance training, aerobic training, or a control group who continued to attend a weekly 2- hour PE class for 16 weeks. The resistance training and aerobic training groups participated in twice weekly supervised after-school exercise sessions of < 1 hour instead of their PE class. Sum of skinfolds, lean body mass (bioelectrical impedance analysis), muscular strength (6 repetition maximum (RM)) bench press, lateral pulldown and leg press) and estimated cardiorespiratory fitness (multistage 20 meter shuttle run) were assessed at pre and post intervention. Complete data were available for n = 40 of the resistance training group, n = 40 of the aerobic training group and n = 30 PE (controls). Resistance training attenuated increases in sum of skinfolds compared with controls (d = 0.27, [0.09-0.36]). We found no significant effect on lean body mass. Resistance training produced a positive effect on muscle strength compared with both controls (d = 0.66 [.49-.86]) and aerobic training (d = 0.55[0.28-0.67]). There was a positive effect of resistance training on cardiorespiratory fitness compared with controls (d = 0.04 [-0.10-0.12]) but not compared with aerobic training (d = 0.24 [0.10-0.36]). Replacing a 2-hour PE class with two 1 hour resistance training sessions attenuated gains in subcutaneous adiposity, and enhanced muscle strength and aerobic fitness development in Colombian youth, based on a median attendance of approximately 1 session a week. Further research to assess whether adequate stimuli for the development of muscular fitness exists within current physical education provision is warranted.

Regulation data for the horizontal jump of children and adolescents

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

Metabolic Health Index (MHI): Assessment of Comorbidity in Bariatric Patients Based on Biomarkers

PURPOSE

The focus of bariatric surgery is reduction of weight, reflected in body mass index (BMI). However, the resolution of comorbidity is a second important outcome indicator. The degree of comorbidity is hard to quantify objectively as comorbidities develop gradually and are interdependent. Multiple scoring systems quantifying comorbidity exist but they lack continuity and objectivity. In analogy with BMI as index for weight, the Metabolic Health Index (MHI) is developed as objective quantification of metabolic health status. Laboratory data were used as comorbidities affect biomarkers. Conversely, laboratory data can be used as objectively obtained variables to describe comorbidity.

METHODS

Laboratory data were collected and crosschecked by national quality registry entries. Machine learning was applied to develop an ordinal logistic regression model, using 4 clinical and 32 laboratory input variables. The output was mathematically transformed into a continuous score for intuitive interpretation, ranging from 1 to 6 (MHI).

RESULTS

In total, 4778 data records of 1595 patients were used. The degree of comorbidity is best described by age at phlebotomy, estimated Glomerular Filtration Rate (eGFR), and concentrations of glycated hemoglobin (HbA1c), triglycerides, and potassium. The model is independent of day of sampling and type of surgery. Mean MHI was significantly different between patient subgroups with increasing number of comorbidities.

CONCLUSION

The MHI reflects severity of comorbidity, enabling objective assessment of a bariatric patient's metabolic health state, regardless day of sampling and surgery type. Next to weight-focused outcome measures like %TWL, the MHI can serve as outcome measure for metabolic health.

Association between muscle strength and risk factors for metabolic syndrome in children and adolescents: a systematic review

The aim of this systematic review was to identify and summarize evidence for the association between muscle strength (MS) and metabolic syndrome (MetS), and MS and combinations of risk factors for MetS in children and adolescents. Five databases (Medline/PubMed, EBSCO, Scielo, Scopus, and Web of Knowledge) were searched up to November 2019 with complementary reference list searches. Inclusion criteria were studies that investigated the relationship between MS and MetS or MS and combinations of risk factors for MetS in children and adolescents (≤19 years of age). Risk of bias was assessed using standard procedures. From the total of 15,599 articles initially identified, 13 articles were included, representing 11,641 children and adolescents. Higher MS values were associated with lower risk for MetS or combinations of risk factors for MetS (n=11/13 studies). Of the total of included studies, about 23.1% (03/13) were longitudinal and all included studies were classified as having a moderate risk of bias. This review provides preliminary evidence for a beneficial relationship between MS and MetS among children and adolescents. Additionally, although the body of evidence points to the beneficial relationship between higher MS and lower risk for combination of factors for MetS in children and adolescents, this relationship is inconclusive.

The Effects of Resistance Training on Blood Pressure in Preadolescents and Adolescents: A Systematic Review and Meta-Analysis

The aim was to systematically review and meta-analyze the current evidence for the effects of resistance training (RT) on blood pressure (BP) as the main outcome and body mass index (BMI) in children and adolescents. Two authors systematically searched the PubMed, SPORTDiscus, Web of Science Core Collection and EMBASE electronic databases. Inclusion criteria were: (1) children and adolescents (aged 8 to 18 years); (2) intervention studies including RT and (3) outcome measures of BP and BMI. The selected studies were analyzed using the Cochrane Risk-of-Bias Tool. Eight articles met inclusion criteria totaling 571 participants. The mean age ranged from 9.3 to 15.9 years and the mean BMI of 29.34 (7.24) kg/m²). Meta-analysis indicated that RT reduced BMI significantly (mean difference (MD): −0.43 kg/m² (95% CI: −0.82, −0.03), P = 0.03; I² = 5%) and a non-significant decrease in systolic BP (SBP) (MD: −1.09 mmHg (95% CI: −3.24, 1.07), P = 0.32; I² = 67%) and diastolic BP (DBP) (MD: −0.93 mmHg (95% CI: −2.05, 0.19), P = 0.10; I² = 37%). Limited evidence suggests that RT has no adverse effects on BP and may positively affect BP in youths. More high-quality studies are needed to clarify the association between RT and BP in light of body composition changes throughout childhood and adolescence.

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.

Handgrip Strength and Current Smoking Are Associated with Cardiometabolic Risk in Korean Adolescents: A Population-Based Study

This study aimed to identify the independent association of handgrip strength and current smoking with cardiometabolic risk in adolescents. Data of 1806 adolescents (12–18 years) from the Korea National Health and Nutrition Examination Surveys were analyzed by complex samples logistic regression analyses. Handgrip strength was normalized by body weight into relative handgrip strength. A cardiometabolic risk index score was calculated from the z-scores of the following components: waist circumference, triglycerides, high-density lipoprotein cholesterol, glucose, and blood pressure. Relative handgrip strength showed an inverse association with high cardiometabolic risk, with an adjusted odds ratio of 8.5 (95% confidence interval [CI], 3.7–19.3) for boys and 5.7 (95% CI, 2.9–11.2) for girls on comparing the lowest and the highest age-and sex-specific quartiles of relative handgrip strength. The adjusted odds ratios for high cardiometabolic risk on comparing the second quartile and the highest quartile of relative handgrip strength were 3.9 (95% CI, 1.7–8.9) in boys and 2.6 (95% CI, 1.3–5.3) in girls. Current smoking was independently associated with high cardiometabolic risk in boys aged 15–18 years. These findings suggest the need to increase muscle strength in adolescents and reduce smoking in older boys to promote cardiometabolic health.

Trends in measures of handgrip strength from 2014 to 2017 among Korean adolescents using the Korean National Health and Nutrition Examination Survey Data

Object

Measuring handgrip strength is a useful method to evaluate sarcopenia. No study has shown the trends of handgrip strength to weight ratio among Korean adolescents by year. This study aimed to determine the trends of handgrip strength among Korean adolescents using data from the Korea National Health and Nutrition Examination Survey (KNHANES). Data of 2304 adolescents who participated in the KNHANES between 2014 and 2017 were obtained. The handgrip-to-weight ratios were categorized by age, sex, and year.

Results

Handgrip strength in adolescents decreased from 28.67 kg in 2014 to 27 kg in 2017 (P for trend < 0.05). The handgrip-to-weight ratio also decreased from 51.48 in 2014 to 48.18 in 2017 (P for trend < 0.05). The handgrip strength and handgrip-to-weight ratio also decreased among boys and girls over the years 2014–2017 (P for trend < 0.05). The results of the present study indicate that the handgrip-to-weight ratio decreased in Korean adolescents from the years 2014 to 2017, and a declining overall ratio indicates a decrease in the health status among Korean adolescents. Hence, there is a need to review the health status of Korean adolescents.

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.

Associations of physical activity and fitness with hepatic steatosis, liver enzymes, and insulin resistance in children with overweight/obesity

BACKGROUND

Non-alcoholic fatty liver disease is the most common liver disease in childhood and is related to insulin resistance and cardiometabolic risk factors. Evidence supporting the association of fitness and physical activity with hepatic fat, liver enzymes, or triglyceride-to-high-density lipoprotein ratio is scarce in children.

OBJECTIVE

To analyze the associations of physical fitness and physical activity (PA) with percentage hepatic fat, liver enzymes, insulin resistance, and cardiometabolic risk in children with overweight/obesity.

SUBJECTS

A total of 115 children (10.6 ± 1.1 years; 54% girls) with overweight/obesity of the EFIGRO study (ClinicalTrials.gov: NCT02258126) were included in the analyses.

METHODS

Cardiorespiratory fitness (CRF), musculoskeletal fitness and speed-agility were measured by the Alpha-fitness tests, and PA by wGT3X-BT accelerometers. Percentage hepatic fat was assessed by magnetic resonance imaging. Alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST), insulin, glucose, triglycerides (TG), and high-density lipoprotein (HDL) levels were obtained from fasting blood samples. The homeostasis model assessment insulin resistance (HOMA-IR) and AST/ALT and TG/HDL ratios were calculated.

RESULTS

Higher CRF was associated with lower percentage hepatic fat (β = -0.266, P = .01) and GGT (β = -0.315, P < .01), and higher AST/ALT ratio (β = 0.306, P < .01). CRF-fit children have lower GGT levels (15 ± 1 vs 17 ± 1 U/L, CRF-fit vs CRF-unfit children, P = .02), HOMA-IR (2.2 ± 0.1 vs 2.9 ± 0.1, P < .01) and TG/HDL ratio (1.4 ± 0.1 vs 1.9 ± 0.1, P = .01) and higher AST/ALT ratio (1.3 ± 0.0 vs 1.2 ± 0.0, P = .03), than CRF-unfit children.

CONCLUSIONS

These findings emphasize the importance of considering the improvement of CRF as a target of programs for preventing hepatic steatosis, type 2 diabetes and cardiovascular diseases in children with overweight.

Latin American Consensus on the management of hypertension in the patient with diabetes and the metabolic syndrome

: The prevalence of hypertension, type 2 diabetes mellitus (DM2) and the metabolic syndrome continues to increase in Latin America, while the rates of diagnosis, treatment and control of these disorders remain low. The frequency of the risk factors that constitute the metabolic syndrome and are associated with an increased risk of cardiovascular disease has not diminished since the publication of the previous consensus. This document discusses the socioeconomic, demographic, environmental and cultural characteristics of most associated Latin American countries and partially explains the lack of better results in improving clinical and public health actions that allow high morbidity and mortality rates caused by cardiovascular diseases and DM2 to be reduced through programs aligned with the so-called precision medicine, which should be predictive, preventive, personalized and participatory. The Consensus ratifies the diagnostic criteria expressed in the previous consensus to define hypertension and DM2 but, for the metabolic syndrome, and in the absence of evidence, the recommendation is to implement a cohort study that determines the abdominal perimeter value associated with hard outcomes, such as DM2 and CVD. Meanwhile, we recommend modifying the criterion to more than 94 cm in men and more than 84 cm in women according to WHO recommendations. We also recommend the carrying out of a study that identifies the situation of hypertension and DM2 in people of African ancestry who, in Latin America, exceed 75 million and whose epidemiology does not include solid studies. With respect to the proposed therapeutic targets, we recommended maintaining those defined in the previous consensus, but insisting that early pharmacological management of prediabetes with metformin should be introduced, as should the treatment of diabetic hypertensive patients with a combination therapy of two fixed-dose antihypertensive drugs and management with statins. To increase adherence, the use of different drugs combined in a single pill (polypill) is recommended. The simplification of the therapeutic regimen is accompanied by greater control of cardiovascular risk factors, both in primary and secondary prevention, and has been shown to be cost-effective. The consensus recommends the use of the currently available polypill combining an angiotensin-converting enzyme inhibitor, a statin and aspirin for secondary cardiovascular prevention and in patients with a high cardiovascular risk, such as hypertension patients with DM2.

Handgrip Strength Among Korean Adolescents With Metabolic Syndrome in 2014-2015

The prevalence of metabolic syndrome is increasing worldwide in adolescents. Metabolic syndrome is a systemic disease that is likely to be associated with other diseases. Studies have shown a relationship between muscle strength, muscle quality, and metabolic syndrome. Handgrip strength is known as a simple tool to measure muscle strength. Therefore, we aimed to investigate the relationship between handgrip strength and metabolic syndrome and each metabolic syndrome features in adolescents. Data were obtained from 1050 adolescents (574 boys, 476 girls; age 10-18 years) who participated in the Korea National Health and Nutrition Examination Survey. We used the International Diabetes Federation metabolic syndrome guideline and National Cholesterol Education Program Adult Treatment Panel III guideline for children to define metabolic syndrome. The highest handgrip strength for both hands was recorded. Handgrip strength was also divided by the participants' own weight (handgrip-to-weight ratio). Adolescents with metabolic syndrome defined by each guideline have higher handgrip strength (p < 0.05). When handgrip strength was divided with participants' own body weight (handgrip-to-weight ratio), values were decreased in participants with metabolic syndrome (p < 0.05). The male participants tend to have higher handgrip-to-weight ratio than female. However, the handgrip-to-weight ratio was found to be decreased regardless of gender when the metabolic syndrome feature was present. This study shows that handgrip strength is associated with metabolic syndrome in adolescents. This is the first study to compare handgrip strength and metabolic syndrome in Korean adolescents. Given that handgrip strength is associated with metabolic syndrome in adolescents, it can be a diagnostic modality to easily identify the patients' current state in the clinic.

Moderation Effect of Handgrip Strength on the Associations of Obesity and Metabolic Syndrome With Fatty Liver in Adolescents

INTRODUCTION/BACKGROUND

This study aimed to evaluate the effect of handgrip strength on the associations of body mass index and metabolic syndrome with an indicator of nonalcoholic fatty liver disease in adolescents.

METHODOLOGY

In data of 1690 adolescents aged 10-18 yr from the Korea National Health and Nutrition Examination Survey 2014-2016, alanine amino-transferase levels, age, sex, bodyweight-, sex-, and age-standardized handgrip strength, age- and sex-specific body mass index Z-scores, and metabolic syndrome severity scores were assessed. Nonalcoholic fatty liver disease was defined based on alanine amino-transferase levels (boys ≥52U/L, girls ≥44U/L) in adolescents who were overweight. Moderation analysis via the PROCESS procedure was performed.

RESULTS

The prevalence of nonalcoholic fatty liver disease was 1.5% among all adolescents and 6.7% among those who were overweight. In all adolescents and adolescents who were overweight, age- and sex-specific body mass index Z-scores and metabolic syndrome scores had positive associations with nonalcoholic fatty liver disease after adjusting for bodyweight-, sex-, and age-standardized handgrip strength. Bodyweight-, sex-, and age-standardized handgrip strength had an inverse association with nonalcoholic fatty liver disease after adjusting for metabolic syndrome scores, and this association became nonsignificant after adjusting for age- and sex-specific body mass index Z-scores. There were positive associations between age- and sex-specific body mass index Z-scores and alanine amino-transferase levels when bodyweight-, sex-, and age-standardized handgrip strength values were ≤-0.13 in overweight adolescents and ≤0.74 in all adolescents, whereas these associations were nonsignificant or negative above those cut-off values. These cut-off values of bodyweight-, sex-, and age-standardized handgrip strength for the relationship between metabolic syndrome scores and alanine amino-transferase levels were -0.15 in overweight adolescents and 0.55 in all adolescents.

CONCLUSIONS

A higher bodyweight-, sex-, and age-standardized handgrip strength may attenuate the risk of obesity and metabolic syndrome for an indicator of nonalcoholic fatty liver disease in adolescents.

Efficacy of School-Based Interventions for Improving Muscular Fitness Outcomes in Adolescent Boys: A Systematic Review and Meta-analysis

BACKGROUND

It has been reported that boys' and girls' physical activity (PA) levels decline throughout adolescence. Boys are at risk of physical inactivity during adolescence; however, in intervention research, they are an under-represented group relative to girls. It is suggested that the school environment may be central to developing interventions that support adolescents in meeting the current PA guidelines. The aim of this systematic review and meta-analysis was to investigate the efficacy of school-based physical activity interventions for improving muscular fitness (MF) in adolescent males.

METHODS

This systematic review and meta-analysis followed the preferred reporting systems for meta-analyses guidelines and was registered on PROSPERO (Registration number: CRD42018091023). Eligible studies were published in English within peer-reviewed articles. Searches were conducted in three databases, with an additional grey literature search in Google Scholar. Studies investigating MF outcomes were included.

RESULTS

There were 43 data sets identified across 11 studies, from seven countries. Overall methodological quality of the studies was moderate-to-strong. Interventions targeting MF evidenced a small-to-medium effect (g = 0.32, CI 0.17, 0.48, p < 0.00). Subgroup analyses of MF delivery method resulted in small-to-medium effects: upper limb MF measures (g = 0.28, 95% CI - 0.02, 0.58, p = 0.07), lower limb MF measures (g = 0.28, 95% CI 0.09, 0.68, p = 0.03), combined MF activities (g = 0.24, 95% CI - 0.04 to 0.49, p = 0.05), plyometric activities (g = 0.39, 95% CI 0.09, 0.68, p = 0.01), body weight (g = 0.27, 95% CI - 0.10, 0.65, p = 0.15), and traditional MF methods (g = 0.43, 95% CI 0.09, 0.78, p = 0.01).

CONCLUSIONS

School-based interventions which aimed to increase MF outcomes in adolescent boys demonstrated small-to-moderate effects. Traditional and plyometric methods of resistance training appear to be the most effective form of PA delivery in adolescent males. More quality research is required to assess the impact of MF delivered in the school environment to inform future intervention design.

Physical Fitness and Somatic Characteristics of the Only Child

The purpose of this study was to examine if only child show differences on somatic growth and physical fitness compared to be a child with siblings. The participants included 542 children (boys: N = 270; girls: N = 270) between 7 and 15 years of age. Somatic growth (height, weight, body mass index) and physical fitness (handgrip strength; flexed harm hang; 60-s sit-ups; standing long jump; 10-m shuttle run and PACER test) were assessed. Variance analysis revealed significant advantages for children with siblings in the flexed arm hang (p = 0.046), 60-s sit-ups (p = 0.002), 10-m shuttle run (p = 0.013) and PACER (p = 0.032). An examination of the possible differential effect of sex on the results revealed no significance for physical fitness variables, but significant interaction were found for weight (p = 0.004) and body mass index (p = 0.005). Despite a lack of interactions between offspring and sex in physical fitness, significant differences between sexes were found in all fitness variables. In conclusion, having siblings showed to be advantageous for general physical fitness in children. This evidence may be used for future analysis and interventions in motor competence, namely considering the growing number of only children in some regions of the world.

Vitamin D, and Maternal and Child Health

Vitamin D has important roles in calcium metabolism and in the prevention of rickets and osteomalacia; low levels of 25-hydroxyvitamin D are common in the general population and amongst pregnant women. Whilst there is a wealth of observational evidence linking vitamin D deficiency to a wide range of disease outcomes, there are currently few high-quality randomised controlled trials to confirm any causal associations, although many are currently in progress. Furthermore, currently, the vast majority of published guidelines recommend standard supplemental vitamin D doses for children and pregnant women, yet there is increasing recognition that individual characteristics and genetic factors may influence the response to supplementation. As such, future research needs to concentrate on documenting definite beneficial clinical outcomes of vitamin D supplementation, and establishing personalised dosing schedules and demonstrating effective approaches to optimising initiation and adherence.

Resistance Training for Older Adults: Position Statement From the National Strength and Conditioning Association

Fragala, MS, Cadore, EL, Dorgo, S, Izquierdo, M, Kraemer, WJ, Peterson, MD, and Ryan, ED. Resistance training for older adults: position statement from the national strength and conditioning association. J Strength Cond Res 33(8): 2019-2052, 2019-Aging, even in the absence of chronic disease, is associated with a variety of biological changes that can contribute to decreases in skeletal muscle mass, strength, and function. Such losses decrease physiologic resilience and increase vulnerability to catastrophic events. As such, strategies for both prevention and treatment are necessary for the health and well-being of older adults. The purpose of this Position Statement is to provide an overview of the current and relevant literature and provide evidence-based recommendations for resistance training for older adults. As presented in this Position Statement, current research has demonstrated that countering muscle disuse through resistance training is a powerful intervention to combat the loss of muscle strength and muscle mass, physiological vulnerability, and their debilitating consequences on physical functioning, mobility, independence, chronic disease management, psychological well-being, quality of life, and healthy life expectancy. This Position Statement provides evidence to support recommendations for successful resistance training in older adults related to 4 parts: (a) program design variables, (b) physiological adaptations, (c) functional benefits, and (d) considerations for frailty, sarcopenia, and other chronic conditions. The goal of this Position Statement is to a) help foster a more unified and holistic approach to resistance training for older adults, b) promote the health and functional benefits of resistance training for older adults, and c) prevent or minimize fears and other barriers to implementation of resistance training programs for older adults.

Low levels of cardiorespiratory fitness and abdominal resistance are associated with metabolic risk in schoolchildren

Background Low levels of physical fitness are associated with metabolic disorders in adults. However, this relationship has been little explored in children and adolescents. The aim of the present study was to investigate whether there is an association between physical fitness related to health and the presence of metabolic risk in schoolchildren. Methods The sample for this cross-sectional study was composed of 1251 schoolchildren of both genders between 7 and 17 years of age. Three indicators of physical fitness related to health were evaluated: cardiorespiratory fitness (CRF), flexibility and abdominal resistance. The continuous metabolic syndrome score (cMetS) was calculated by using the sum of the Z scores of the following indicators: body mass index (BMI), systolic blood pressure, glucose, total cholesterol, high- and low-density lipoprotein cholesterol (HDL-c and LDL-c) and triglycerides. Subsequently, the cMetS was dichotomized, considering the presence or absence of metabolic risk. The data were analyzed using prevalence ratio (PR) values and 95% confidence intervals (CI), using Poisson regression. Results A higher prevalence of metabolic risk was found among students with low levels of CRF (PR: 1.48; CI: 1.10-1.98) and abdominal resistance (PR: 1.45; CI: 1.08-1.95). No association with flexibility was found. Conclusions Low levels of CRF and abdominal resistance are associated with the presence of metabolic risk in schoolchildren.

Handgrip strength attenuates the adverse effects of overweight on cardiometabolic risk factors among collegiate students but not in individuals with higher fat levels

The aims of this study are to (i) examine a clustered metabolic syndrome composite score (MetScore) and fatness among college students across body mass index (BMI) categories, and (ii) determine whether fit individuals have lower MetScores, fewer individual metabolic syndrome components, and lower fatness than unfit individuals across BMI categories. A total of 1,795 participants aged  >18 years who participated in The FUPRECOL Study were selected for the present analyses. Handgrip strength was tested by a grip dynamometer and used to classify adults as fit or unfit. Among all participants, MetScore, percentage of body fat, and visceral adiposity increased linearly across the BMI categories among college students (all P < 0.001). Individuals who were overweight and fit had a lower MetScore (-0.6 SD; P = 0.02), body fat percentage (-2.6%; P < 0.001) and visceral adiposity (-0.2; P = 0.01) than unfit peers. Moderately fit obese individuals had significantly lower visceral fat levels than unfit obese peers (-3.0; P = 0.03). These results suggest that having adequate handgrip strength-a proxy of overall strength capacity-may attenuate obesity-related cardiometabolic risk. Moreover, weight loss should be recommended to all individuals with obesity, even among those who are currently considered fit.

Manejo interprofesoral de las enfermedades cardiovasculares

Se conocen como enfermedades cardiovasculares (ECV) al infarto agudo de miocardio (IAM), el accidente cerebrovascular (ACV) isquémico o hemorrágico y la enfermedad vascular periférica, también conocidas como enfermedades vasculares ateroscleróticas, pues tienen en común que el proceso fisiopatológico básico es el desarrollo de aterosclerosis en la vasculatura que irriga a los órganos afectados. El IAM y ACV son eventos agudos que se deben principalmente a obstrucciones en los vasos, las cuales se presentan cuando se produce ruptura de una placa aterosclerótica ocasionando un cuadro de atero-trombosis, fenómeno que explica la sintomatología de los eventos agudos. Actualmente las ECV se constituyen en la primera causa de morbi-mortalidad en todo el mundo, ocasionando que cada año mueran más personas por estas enfermedades que por cualquier otra causa. Según la Organización Mundial de la Salud (OMS), anualmente 17,5 millones de personas en el mundo, es decir el 31% de las defunciones totales mueren a causa de alguna ECV, siendo que 7,4 millones se debe a IAM y 6,7 millones AVC.  Las ECV son consideradas al momento como una epidemia global que afecta a individuos de todos los países, independientemente de sus ingresos económicos, pero que han tenido un gran incremento en los países de ingresos medianos y bajos, afectando casi por igual a ambos sexos. Actualmente las ECV en su conjunto son la principal causa de muerte en Colombia, con el IAM ocasionando el 17% de la mortalidad general, tanto en hombres como en mujeres, seguida por el ACV y las enfermedades hipertensivas.Como citar este artículo: Lopez-Jaramillo P, Rueda-García D. Manejo interprofesoral de las enfermedades cardiovasculares. Rev Cuid. 2019; 10(2): e756. http://dx.doi.org/10.15649/cuidarte.v10i2.756

Low muscle mass and strength in pediatrics patients: Why should we care?

Skeletal muscle plays major roles in metabolism and overall health across the lifecycle. Emerging evidence indicates that prenatal (maternal diet during pregnancy and genetic defects) and postnatal factors (physical activity, hormones, dietary protein, and obesity) influence muscle mass acquisition and strength early in life. As a consequence, low muscle mass and strength contributes to several adverse health outcomes during childhood. Specifically, studies demonstrated inverse associations of muscle mass and strength to single and clustered metabolic risk factors. The literature also consistently reports that low muscle mass and strength are associated with reduced bone parameters during growth, increasing the risk of osteoporosis in old age. Furthermore, muscle mass gains are associated with improved neurodevelopment in the first years of life. Given these negative implications of low muscle mass and strength on health, it is crucial to track muscle mass and strength development from childhood to adolescence. Several body composition techniques are currently available for estimation of muscle mass, all with unique advantages and disadvantages. The value of ultrasound as a technique to measure muscle mass is emerging in pediatric research with potential for translating the research findings to clinical settings. For the assessment of muscle strength, the handgrip strength test has been widely employed but without a standardized protocol. Although further research is needed to define normative data and cut points for the low muscle mass and strength phenotype, the use of such non-invasive medical monitoring is a promising strategy to identify early abnormalities and prevent low muscle mass in adulthood.

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.

Skeletal muscle reference for Chinese children and adolescents

BACKGROUND

Skeletal muscle as an essential body composition component plays an important role in maintenance of normal growth and development as well as systemic glucose metabolism in children. No nationwide reference data for skeletal muscle mass for Chinese youths are available in China. We aimed to establish the sex-specific and age-specific percentile reference values of skeletal muscle mass for Chinese children and adolescents.

METHODS

This study consisted of 10 818 children and adolescents aged 3-17 years in Chinese urban area during 2013-15. Dual-energy X-ray absorptiometry scan was performed to measure whole body muscle mass and appendicular skeletal muscle mass. Lambda-mu-sigma method was used to obtain the sex-specific and age-specific percentile curves of muscle mass indices.

RESULTS

Overall, whole body muscle mass and appendicular skeletal muscle mass indices showed an increasing trend with age for both sexes, with boys vs. girls having higher values of all muscle mass indices. Whole body muscle mass index in boys increased slightly before age 9 years and then increased rapidly until 15 years and slowed down thereafter, while the mean values in girls increased slightly before age 8 years, increased rapidly until 14 years and remained stable thereafter. Appendicular skeletal muscle mass index increased rapidly until age 16 years and then increased slightly for boys; by contrast, for girls, the mean values increased consistently before age 14 years but showed a slightly decreasing trend after that.

CONCLUSIONS

This study established sex-specific and age-specific percentile reference values for skeletal muscle mass for Chinese children and adolescents aged 3-17 years. These reference values can be used to evaluate the muscular development in Chinese children and adolescents.

Effectiveness of a school-based physical activity intervention on adiposity, fitness and blood pressure: MOVI-KIDS study

OBJECTIVE

To test a physical activity intervention (MOVI-KIDS) on obesity indicators, physical fitness and blood pressure (BP) in children.

METHODS

A crossover randomised cluster trial was conducted, which comprised 1434 children (4-7 years old) from 21 schools in the provinces of Cuenca and Ciudad Real in the Castilla-La Mancha region of Spain. The intervention consisted of three 60 min sessions/week on weekdays between October 2013 and May 2014. Changes in anthropometric variables, physical fitness and BP parameters were measured. The analyses used were mixed regression models to adjust for baseline covariates under cluster randomisation.

RESULTS

There was no significant improvement in overweight/obesity with the intervention compared with the control group in both sexes. Further, the intervention did not alter other adiposity indicators or BP parameters. Improvements in cardiorespiratory fitness were seen in girls (1.19; 95% CI 0.31 to 2.08; p=0.008), but not in boys. Finally, there was an improvement in velocity/agility in both girls (-2.51 s; 95% CI -3.98 to -1.05; p=0.001) and boys (-2.35 s; 95% CI -3.71 to -0.98; p=0.001), and in muscular strength in both girls (0.66; 95% CI 0.03 to 1.28; p=0.038) and boys (1.26; 95% CI 0.03 to 1.28; p<0.001).

CONCLUSION

MOVI-KIDS was not successful in reducing the adiposity and maintained BP levels at previous healthy values in children. The intervention, however, showed significant improvements in cardiorespiratory fitness in girls, and muscular strength and velocity/agility in boys and girls.

TRIAL REGISTRATION NUMBER

NCT01971840; Post-results.

Muscle Mass in Children and Adolescents: Proposed Equations and Reference Values for Assessment

Objectives: The goal of this study was to develop regression equations to estimate LM with anthropometric variables and to propose percentiles for evaluating by age and sex. Methods: A cross sectional study was conducted with 2,182 Chilean students (1,347 males and 835 females). Ages ranged from 5.0 to 17.9 years old. A total body scan was carried out with the double energy X-ray anthropometry (DXA) to examine and measure lean muscle mass of the entire body. Weight, height, and the circumference of the relaxed right arm were also measured. Results: Four anthropometric equations were generated to predict lean mass for both sexes (R ² = 83-88%, SEE = 3.7-5.0%, precision = 0.90-0.93, and accuracy = 0.99). The Lambda-mu-sigma method was used to obtain the sex-specific and age-specific percentile curves of lean mass (p3, p5, p10, p15, p25, p50, p75, p85, p90, p95, and p97). Conclusion: The four proposed equations were acceptable in terms of precision and accuracy to estimate lean mass in children and adolescents. The percentiles were created by means of anthropometric equations and real values for DXA. These are fundamental tools for monitoring LM in Chilean children and adolescents of both sexes.

Is willingness to exercise programmed in utero? Reviewing sedentary behavior and the benefits of physical activity in intrauterine growth restricted individuals

OBJECTIVE

The literature suggests that a fetus will adapt to surrounding adversities by optimizing its use of energy to improve survival, ultimately leading to the programming of the individual's energy intake and expenditure. While recent reviews focused on the fetal programming of energy intake and food preferences, there is also some evidence that fetal adversity is associated with diminished physical activity levels. Therefore, we aimed to review (a) the evidence for an association between being born with intrauterine growth restriction and sedentarism over the life-course and (b) the potential benefits of physical activity over cardiometabolic risk factors for this population.

SOURCES

PubMed, Scielo, Scopus and Embase.

SUMMARY OF FINDINGS

Most clinical studies that used objective measures found no association between intrauterine growth restriction and physical activity levels, while most studies that used self-reported questionnaires revealed such relationships, particularly leisure time physical activity. Experimental studies support the existence of fetal programming of physical activity, and show that exposure to exercise during IUGR individuals' life improves metabolic outcomes but less effect was seen on muscle architecture or function.

CONCLUSIONS

Alterations in muscle strength and metabolism, as well as altered aerobic performance, may predispose IUGR individuals to be spontaneously less physically active, suggesting that this population may be an important target for preventive interventions. Although very heterogeneous, the different studies allow us to infer that physical activity may have beneficial effects especially for individuals that are more vulnerable to metabolic modifications such as those with IUGR.