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

Physical Activity, Fitness, and Cardiovascular Disease Risk in Adolescent Childhood Cancer Survivors Compared to Controls: The Physical Activity in Childhood Cancer Survivors Study

Purpose: Childhood cancer survivors have increased risk of cardiac late effects that can be potentially mitigated by physical activity and fitness. We aimed to (1) compare cardiovascular disease (CVD) risk between survivors and controls, and (2) examine whether the associations of moderate-to-vigorous physical activity (MVPA), cardiorespiratory fitness (CRF), and musculoskeletal fitness (MSF) with CVD risk factors differed between survivors and controls. Methods: Within the Physical Activity in Childhood Cancer Survivors (PACCS) study, we assessed CVD risk factors (android fat mass, systolic blood pressure [SBP], total cholesterol/high-density lipoprotein [HDL]-cholesterol, and glycosylated hemoglobin) in 157 childhood cancer survivors and 113 age- and sex-matched controls aged 9-18 years. We used multivariable mixed linear regression models to compare CVD risk factors between survivors and controls, and assess associations of MVPA, CRF, and MSF with CVD risk factors. Results: Compared with controls, survivors had more android fat mass (861 vs. 648 g, p = 0.001) and lower SBP (114 vs. 118 mmHg, p = 0.002). MVPA, CRF, and MSF were associated with lower levels of android fat mass and total cholesterol/HDL-cholesterol, and higher SBP in survivors. Associations of MVPA, CRF, and MSF with CVD risk factors were similar in survivors and controls (Pinteraction > 0.05), except the associations of CRF and MSF with android fat mass, which were stronger in survivors than in controls (Pinteraction ≤ 0.001). Conclusion: Owing to higher levels of android fat mass and its stronger association with physical fitness in childhood cancer survivors compared with controls, survivors should get targeted interventions to increase fitness to reduce future risk of CVD.

Muscle Strength Indexes and Its Association With Cardiometabolic Risk Factors in Adolescents: An Allometric Approach

Background and aims: Muscle strength (MS) has been associated with better cardiometabolic health prognosis. However, the result for the beneficial relationship seems to be dependent on the influence of body size in determining MS levels. We investigate the association between allometric MS indexes and its association with cardiometabolic risk factors in adolescents. Methods: It was a cross-sectional study comprising 351 adolescents (male: 44.4%; age range 14-19 years) from Southern Brazil. MS was assessed by handgrip strength and three different allometric approaches were adopted: 1) MS index based on theoretical allometric exponent; 2) MS index including body mass and height; 3) MS index including fat-free mass and height. Obesity, high blood pressure, dyslipidemia, glucose imbalance and high-sensitivity C-reactive protein were investigated as individual factors or as combinations (either as combinations of components - presence of two adverse conditions, or number of components present in an individual - 0, 1, 2, 3+ cardiometabolic risk factors). Logistic and multinomial logistic regression analyses adjusted for confounding factors were used. The statistical significance adopted was 5%. Results: MS index based on theoretical allometric exponent was associated with lower likelihood (OR: 0.54; 95% CI: 0.28 - 0.89) for the presence of three or more cardiometabolic risk factors in the same individual. Conclusion: This study suggests that MS index based on the theoretical allometric exponent can be superior to allometric MS indexes that included body mass and height, or fat-free mass and height in representing the presence of high number of cardiometabolic risk factors in adolescents.

The impact of reduced muscular fitness on cardiometabolic risk factors in children aged 9-11 years

AIM

To analyse the relationships between muscular fitness (MF), fat mass (FM), fat-free mass (FFM) and its combined ratio with cardiometabolic risk (CMR) and whether the relationship between MF and CMR is mediated by body composition in schoolchildren.

METHODS

A cross-sectional study was conducted on schoolchildren from Cuenca, Spain, between September and November 2017. FM and FFM were estimated using bioimpedance analysis. The CMR index was calculated from triglycerides-HDL-c ratio, arterial pressure and fasting insulin. The MF index was assessed using handgrip and standing long jump tests. Analysis of covariance models assessed CMR index differences across the MF index and the FM/FFM ratio categories. Mediation analysis examined whether the MF index and the CMR index association were mediated by FM, FFM or FM/FFM ratio.

RESULTS

The analyses involved 485 schoolchildren aged 9-11 years (55.4% girls). Children with a higher MF index had a lower CMR index (p < 0.05). This association did not persist after controlling for FM/FFM. FM, FFM and FM/FFM ratio mediated the relationship between the MF index and the CMR index.

CONCLUSION

Better levels of MF are associated with better cardiometabolic profile, but a healthy body composition is determinant to improve future health.

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

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

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.

Association of muscle strength and body mass index with risk factors for metabolic syndrome and its prevalence in Korean adult women

Background

The aim of this study was to investigate the effects of muscle strength and BMI (body Mass Index) on Metabolic syndrome (MetS) risk factors and prevalence in Korean adult women, using data from the Korea National Health and Nutrition Examination Survey.

Methods

A total of 3189 Korean adults women participated in the cross-sectional study. Participants were measured BMI, MetS risk factors including waist-circumference (WC), fasting glucose (FG), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), and handgrip strength as muscle strength.

Results

As a result ‘high BMI & Low muscle strength’, ‘low BMI & low muscle strength’, and ‘high BMI & high muscle strength’ groups had a significantly higher prevalence of Mets [OR (Odd ratio): 1.49, 95% CI (confidence interval): 1.01 2.20; OR: 5.77, 95% CI: 4.32 7.17; OR: 10.46, 95% CI: 8.05 13.59] than ‘low BMI & high muscle strength’ group; and after adjusting smoking, menstruation status, and drinking rate, the OR were 1.07 (95% CI: 0.71–1.61), 4.89 (95% CI: 3.60–6.55), and 7.38 (95% CI: 5.63–9.68), respectively.

Conclusions

These findings indicated that increasing muscle strength and lowering BMI through regular physical activity and exercise are effective methods to reduce the prevalence of risk factors for Mets.

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.

Muscle strength and its association with cardiometabolic variables in adolescents: does the expression of muscle strength values matter?

BACKGROUND

We investigate the association between different muscle strength (MS) indices with cardiometabolic variables in adolescents.

METHODS

Cross-sectional study comprising 351 adolescents (male 44.4%, age 16.6 ± 1.0 years) from Brazil. MS was assessed by handgrip strength and analyzed in five different ways: absolute MS and MS normalized for body weight, body mass index (BMI), height, and fat mass, respectively. Cardiometabolic variables investigated as outcomes were systolic and diastolic blood pressure (DBP), waist circumference (WC), high-sensitive C-reactive protein (hs-CRP), lipid and glucose metabolism markers. Multiple linear regression models adjusted for confounding factors were used.

RESULTS

Absolute MS and/or MS normalized for height was directly associated with WC [up to 32.8 cm, standard error (SE) = 4.7] and DBP (up to 8.8 mmHg, SE = 0.8), and inversely associated with high-density lipoprotein cholesterol (up to -8.0 mg/dL, SE = 14.1). MS normalized for body weight, BMI or fat mass was inversely associated with WC (up to -17.5 cm, SE = 2.2). According to sex, MS normalized for fat mass was inversely associated with triglycerides (male: 0.02 times lower, SE = 0.01; female: 0.05 times lower, SE = 0.01) and homeostatic model assessment for insulin resistance (male: 0.02 times lower, SE = 0.01; female: 0.06 times lower, SE = 0.01), and inversely associated with hs-CRP only among male (0.03 times lower, SE = 0.01).

CONCLUSION

When normalized for body weight, BMI or fat mass, MS was superior to absolute MS or MS normalized for height in representing adequately cardiometabolic variables among adolescents.

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.

Effects of Whole-Body Vibration Training on Body Composition, Cardiometabolic Risk, and Strength in the Population Who Are Overweight and Obese: A Systematic Review With Meta-analysis

OBJECTIVES

To assess the effects of whole-body vibration training (WBVT) on body composition, metabolic and cardiovascular risk variables, and lower limb strength in participants who are overweight/obese.

DATA SOURCES

A systematic review with meta-analysis was conducted in 3 databases (PubMed-MEDLINE, Web of Science, and Cochrane Library) from inception through to January 26, 2020.

STUDY SELECTION

Studies analyzing the effect of WBVT on body composition variables, metabolic profile, blood pressure, heart rate, and lower limb strength in the population who are overweight/obese, with interventions of a minimum length of 2 weeks were included.

DATA EXTRACTION

After applying the inclusion and exclusion criteria, 23 studies involving 884 participants who were obese/overweight (experimental group: 543; weight=79.9 kg; body mass index (BMI) =31.3 kg/m², obesity class I according to World Health Organization) were used in the quantitative analysis. The sex of the participants involved in the studies were as follows: (1) 17 studies included only female participants; (2) 1 study included only boys, and (3) 5 studies included both sexes. Meta-analysis, subgroup analysis, and meta-regression methods were used to calculate the mean difference and standardized mean difference (SMD; ± 95% confidence intervals [CIs]) as well as to analyze the effects of pre-post intervention WBVT and differences from control groups.

DATA SYNTHESIS

WBVT led to a significant decrease in fat mass (-1.07 kg, not clinically significant). In addition, WBVT reduced systolic blood pressure (-7.01 mmHg, clinically significant), diastolic blood pressure (-1.83 mmHg), and heart rate (-2.23 bpm), as well as increased the lower extremity strength (SMD=0.63; range, 0.40-0.86). On the other hand, WBVT did not modify the weight, BMI, muscle mass, cholesterol, triglycerides, or glucose.

CONCLUSIONS

WBVT could be an effective training modality to reduce blood pressure (clinically relevant) and resting heart rate. In addition, WBVT led to improved lower limb strength. However, these findings were not consistent with significant improvements on other variables associated with metabolic syndrome (body composition, cholesterol, triglycerides, glucose).

Report Card Brazil: systematic review of muscle strength assessment in children and adolescents in Brazil

ABSTRACT The present study aimed to identify and summarize evidence regarding muscle strength (MS) levels in school children and adolescents (≤ 19 years) in Brazil in order to update previously published evidence from the Report Card Brazil project. The systematic search for information was conducted in seven databases, restricted to studies published during the period from January 2018 to December 2019. Thirteen studies were included, which gathered information from 10,135 children and adolescents from seven Brazilian states. Different tests/protocols for assessing MS were identified, however, handgrip strength was the test most adopted in studies (53.8%). The prevalence of children and adolescents with MS levels considered healthy was 29.8%, considering the totality of information, and 27.6% for males and 31.8% for females. Considering full data reviewed by the Report Card Brazil project (data analyzed in this study in addition to those previously published), information regarding the assessment of MS levels in children and adolescents in Brazil came from studies conducted during the period from 2010 to 2019, which included a sample of 15,208 children and adolescents (aged 7-19 years). According to this information, the prevalence of children and adolescents with MS levels considered healthy in this period was 57.8%, 61.1% for males and 58.8% for females.