Muscle strength in adolescent men and risk of cardiovascular disease events and mortality in middle age: a prospective cohort study

Effects of Exercise Type on Muscle Strength and Body Composition in Men and Women: A Systematic Review and Meta-Analysis

Background and Objectives: There are typical differences in body composition and distribution of muscle fiber types between women and men. However, research investigating the effects of exercise based on sex differences is limited, and studies examining sex differences in physiological adaptations according to exercise type are scarce. We aimed to compare the effects of exercise types on muscle strength and body composition in men and women through a meta-analysis. Materials and Methods: A systematic literature search was conducted using the PubMed/Medline, Web of Science, CINAHL, and EBSCO databases. Keywords included "endurance training", "resistance training", "concurrent training", "muscle strength", "body composition", "sex characteristics", and "men and women". The standardized mean difference (SMD) was presented separately for men and women based on the pre- and post-intervention values for each exercise type. Results: Concurrent training showed the greatest effect on the increase in leg press muscle strength in men, and resistance training showed the greatest effect in women. Concurrent training showed the greatest effect size in both men and women in increasing bench press muscle strength. Resistance training and concurrent training showed a small effect size on lean mass reduction in both men and women. Endurance training and concurrent training significantly reduced fat mass in men. However, no significant changes in fat mass were observed in any exercise type among women. Conclusions: Concurrent training is the most efficient type of exercise for men, as it is effective in increasing upper- and lower-body muscle strength, increasing lean mass, and reducing fat mass. Resistance training is most effective in increasing muscle strength in females, whereas endurance training is most effective in reducing fat mass. However, it is difficult to corroborate these results because of the lack of study samples included in the analysis and the differences in exercise methods, participant age, and exercise duration.

Resistance training effects on pubertal children with a risk of developing pediatric dynapenia

PURPOSE

Many modern-day children are at risk of pediatric dynapenia (muscle weakness). We examined the effects of a 12-week resistance training (RT) program on neuromuscular function and body composition parameters in pubertal children with a risk of dynapenia.

METHODS

Twelve children (13.4 ± 0.9 y) with dynapenia performed a progressive RT program consisting of knee extension and flexion, bench press, abdominal crunch, back extension, lateral pull-down, elbow flexion, and upright row (1-2 sets of 10-15 repetitions/exercise) twice/week for 12 weeks. Outcome measures included one-repetition maximum (1-RM) strength, maximal voluntary isometric contraction (MVIC) torque, rate of torque development (RTD), electromyographic (EMG) activity, muscle thickness (MT), muscle quality (MQ) assessed by echo intensity (MQEI) of the knee extensors and specific tension of MVIC torque to thigh fat-free mass (MQST), and total and regional body and bone composition assessed by dual-energy X-ray absorptiometry. Changes in the measures before and after the 12-week RT and associations among the measures were analyzed by linear mixed models.

RESULTS

Significant (p < 0.05) increases in 1-RM (63.9 ± 4.5%), MVIC torque (16.3 ± 17.8%), MT (18.8 ± 5.5%) and MQ (MQEI: -25.9 ± 15.2%; MQST: 15.1 ± 18.8%;) were evident from pre- to post-training. Total fat-free mass (FFM) increased by 2.3 ± 3.2% from baseline (p = 0.01), but no changes (p > 0.05) in the other measures were observed. Significant (p < 0.05) associations between the changes in 1-RM and/or MVIC torque and the changes in quadriceps MT, MQEI, MQST and total body FFM were evident.

CONCLUSIONS

The 12-week RT was effective for improving neuromuscular and body composition parameters, and thereby reversed the risk of pediatric dynapenia.

Post-natal muscle growth and protein turnover: a narrative review of current understanding

A model explaining the dietary-protein-driven post-natal skeletal muscle growth and protein turnover in the rat is updated, and the mechanisms involved are described, in this narrative review. Dietary protein controls both bone length and muscle growth, which are interrelated through mechanotransduction mechanisms with muscle growth induced both from stretching subsequent to bone length growth and from internal work against gravity. This induces satellite cell activation, myogenesis and remodelling of the extracellular matrix, establishing a growth capacity for myofibre length and cross-sectional area. Protein deposition within this capacity is enabled by adequate dietary protein and other key nutrients. After briefly reviewing the experimental animal origins of the growth model, key concepts and processes important for growth are reviewed. These include the growth in number and size of the myonuclear domain, satellite cell activity during post-natal development and the autocrine/paracrine action of IGF-1. Regulatory and signalling pathways reviewed include developmental mechanotransduction, signalling through the insulin/IGF-1-PI3K-Akt and the Ras-MAPK pathways in the myofibre and during mechanotransduction of satellite cells. Likely pathways activated by maximal-intensity muscle contractions are highlighted and the regulation of the capacity for protein synthesis in terms of ribosome assembly and the translational regulation of 5-TOPmRNA classes by mTORC1 and LARP1 are discussed. Evidence for and potential mechanisms by which volume limitation of muscle growth can occur which would limit protein deposition within the myofibre are reviewed. An understanding of how muscle growth is achieved allows better nutritional management of its growth in health and disease.

Leg strength and incidence of heart failure in patients with acute coronary syndrome

AIMS

The risk of developing heart failure (HF) after acute coronary syndrome (ACS) remains high. It is unclear whether skeletal muscle strength, in addition to existing risk factors, is a predictor for developing HF after ACS. We aimed to clarify the relationship between quadriceps isometric strength (QIS), a skeletal muscle strength indicator, and the risk of developing HF in patients with ACS.

METHODS AND RESULTS

We included 1053 patients with ACS without a prior HF or complications of HF during hospitalization. The median (interquartile range) age was 67 (57-74) years. The patients were classified into two groups-high and low QIS-using the sex-specific median QIS. The endpoint was HF admissions. During a mean follow-up period of 4.4 ± 3.7 years, 75 (7.1%) HF admissions were observed. After multivariate adjustment, a high QIS was associated with a lower risk of HF [hazard ratio: 0.52, 95% confidence interval (CI): 0.32-0.87]. Hazard ratio (95% CI) per 5% body weight increment increase of QIS for HF incidents was 0.87 (0.80-0.95). Even when competing risks of death were taken into account, the results did not change. The inclusion of QIS was associated with increases in net reclassification improvement (0.26; 95% CI: 0.002-0.52) and an integrated discrimination index (0.01; 95% CI: 0.004-0.02) for HF.

CONCLUSION

The present study showed that a higher level of QIS was strongly associated with a lower risk of developing HF after ACS. These findings suggest that skeletal muscle strength could be one of the factors contributing to the risk of developing HF after ACS.

Healthy fitness zone prevalence and age-specific fitness profile of young people in seven European countries in 2022: The EUFITMOS project

BACKGROUND

Physical fitness is a health marker in youth and is associated with current and future health.

OBJECTIVE

Present the healthy fitness zone (HFZ) prevalence and age-specific fitness profile of young people from seven European countries.

METHODS

This study used data from the European Fitness Monitoring System project. The sample comprised 4965 (51.4% boys) youths aged 9 to 18 years. Fitness data were collected by physical education teachers using field-based tests. Raw data from the fitness tests were used to calculate the prevalence and 95% confidence intervals (CI) of participants in the HFZ.

RESULTS

The overall prevalence of boys and girls in the HFZ for all tests was 16.6% (95% CI = 14.7, 18.1) and 14.9% (95% CI = 13.2, 16.6), respectively. Boys have a mainly positive HFZ profiles, except for the 9-year-olds in the sit and reach (z-score difference = -1.20) and the 20 m run for boys 13-18-year-olds (z-score difference range: -0.09 to -0.01). Girls have worse HFZ profiles than boys, being out of the HFZ in several tests. Furthermore, a decreasing trend in z-score difference from the HFZ with age was observed in VO2 peak for boys and girls and sit and reach for girls. Notwithstanding, several country-related, sex and age differences were observed.

CONCLUSIONS

Boys presented mostly healthy age-specific fitness profiles in several fitness tests and ages. These differences should be considered when promoting youth's health through physical activity and fitness, as different fitness levels may require different approaches to implementing health-enhancing physical activity policies.

May the Force Be with Youth: Foundational Strength for Lifelong Development

ABSTRACT

Today's youth are weaker than previous generations, and measurable reductions in physical fitness are beginning to emerge. Without targeted initiatives that recognize the foundational importance of resistance training, weaker children and adolescents may be more likely to experience the inevitable consequences of neuromuscular dysfunction and less likely to experience the pleiotropic benefits of exercise and sport. Early exposure to strength-building activities is needed to prepare today's youth for ongoing participation in varied physical activities throughout this developmental phase of life. The novel iceberg of physical development is a metaphoric image that illustrates the sequential and cumulative influence of muscular strength on motor skills and physical abilities. Efforts to enhance the physical capacity of youth should include resistive skills that improve basic movement patterns and enhance motoric competence. A shift in our conceptual thinking about youth resistance training is needed to alter the current trajectory toward physical inactivity and related comorbidities.

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

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

Effects of resistance training and protein supplementation interventions on muscle volume and muscle function: sex differences in humans

PURPOSE

This review aimed to identify differences in the effects of co-intervention with resistance training (RT) and protein supplementation according to sex and provide meaningful information for future research on the development of exercise programs to improve muscle volume and muscle function.

METHODS

PubMed, Science Direct, and Google Scholar were searched to identify clinical and nonclinical studies that assessed the effects of RT in older adults with sarcopenia; these studies were published between 1990 and 2023. Cross-sectional and double-blind studies (randomized controlled trials, RCTs) were examined in this review.

RESULTS

The effects of parallel intervention with RT and protein supplementation on muscle volume and physical function were found to differ according to sex. Both males and females had improvements in muscle strength, muscle mass, and physical function after RT and protein supplementation; however, many studies found a greater increase in muscle volume and function in males than in females. Such difference may be due to differences in physiological characteristics between males and females.

CONCLUSION

Based on the findings of this review, the effects of combined intervention with RT and protein supplementation on muscle strength, muscle mass, and physical function to differ according to sex. Owing to these sex differences in the response and physiological characteristics caused by the parallel intervention of RT and protein supplementation, such differences must be considered to maximize the effects of RT and protein supplementation.

Beneficial Effects of Asparagus officinalis Extract Supplementation on Muscle Mass and Strength following Resistance Training and Detraining in Healthy Males

The phytoecdysteroid 20-hydroxyecdysone (20E) is widely used for resistance training (RT). Little is known about its potential ergogenic value and detraining effects post-RT. This study aimed to examine the effects of 20E extracted from Asparagus officinalis (A. officinalis) on muscle strength and mass, as well as anabolic and catabolic hormones following RT and detraining. Twenty males, aged 20.1 ± 1.1 years, were matched and randomly assigned to consume double-blind supplements containing either a placebo (PLA) or 30 mg/day of 20E for 12 weeks of RT and detraining. Before and after RT and detraining, muscle strength and mass and anabolic and catabolic hormones were measured. This study found that 20E reduced cortisol levels significantly (p < 0.05) compared to the PLA, yet no effect was observed on muscle mass, strength, or anabolic hormones after RT. Subsequent to 6 weeks of detraining, the 20E demonstrated a lower percentage change in 1RM bench press/FFM than the PLA (p < 0.05). Compared to the PLA, detraining throughout the 12 weeks resulted in a lower percentage change in thigh (p < 0.05) and chest (p < 0.01) circumferences, as well as reduced cortisol levels (p < 0.01), with 20E. Our findings demonstrate that 20E supplementation is a promising way to maintain muscle mass and strength during detraining. Accordingly, 20E may prevent muscle mass and strength loss due to detraining by lowering catabolic hormone levels.

Temporal Trends in the Physical Fitness of Hong Kong Adolescents Between 1998 and 2015

Low physical fitness in adolescence is linked with increased cardiometabolic risk and early all-cause mortality. This study aimed to estimate temporal trends in the physical fitness of Hong Kong adolescents aged 12-17 years between 1998 and 2015. Physical fitness (9-min run/walk, sit-ups, push-ups, and sit-and-reach) and body size data in a total of 28,059 adolescents tested across five population-representative surveys of Hong Kong secondary school pupils, were reported. Temporal trends in means were estimated at the gender-age level by best-fitting sample-weighted linear regression, with national trends estimated by a post-stratified population-weighting procedure. Overall, there were small declines in 9-min run/walk (effect size (ES)=-0.29 (95%CI: -0.32, -0.26)) and sit-ups performance (ES=-0.24 (95%CI: -0.27, -0.21)), with negligible changes in push-ups and sit-and-reach performance. There were small concurrent increases in both mean height and body mass, with a negligible increase in sum of skinfolds. Trends in mean physical fitness and body size/were not always uniform across the population distribution. The small declines in mean 9-min run/walk and sit-ups performance for Hong Kong adolescents are suggestive of corresponding declines in cardiorespiratory fitness and abdominal/core endurance, respectively. Increased national health promotion strategies are required to improve existing trends.

Exploring the Relationship Between the Indices of Body Composition With Grip Strength Performance and Peak VO2

Background The importance of measurements of body composition in terms of various indices including Body Mass Index (BMI), Body Surface Area (BSA), Body Size Index (BSI), and Waist to Height ratio (WtHR) in the diagnosis of health risks and mortality outcome analysis has largely been limited to their use relating to determining abdominal obesity. The understanding of the extent of implications of the newer, underutilized indices of body composition is deficient. Peak VO₂ (maximal oxygen uptake) majorly serves for the evaluation of the measure of aerobic capacity. Grip strength performance is a simple, primary, objective predictor of overall physical status and muscular and cardiovascular fitness. This study aimed to derive the relationship between a gamut of parameters such as BMI, BSA, WtHR, BSI, grip strength performance and peak VO₂ investigated using the latest scientific methodology in a cross-section of the population in a rural tertiary care center. Methodology This study was a descriptive, cross-sectional study carried out in a rural medical college in central India. Sixty participants from the healthcare setting were considered eligible for the study within the age group of 18 to 45 years. Anthropometric assessments like height (in cm), weight (in kg), waist circumference (in cm), and BMI were carried out. BSA, WtHR, and BSI were calculated using the respective formulae. VO₂ max (maximal oxygen uptake) recordings were done using the treadmill/ergometer and metabolic module of LabChart software (Bella Vista, New South Wales, Australia). Grip Strength Performance was quantified by measuring the amount of static force with which the hand is able to squeeze a transducer. It was measured using Grip Force Transducer (MLT004 / ST) from AD Instruments (Bella Vista, New South Wales, Australia). Results Upon analysis, a significant negative correlation was obtained between BSI and BMI (r= -0.51, p<0.0001) whereas a significant positive correlation was found between BSA and BMI (r= 0.71, p< 0.0001). A significant correlation was also seen between WtHR and BMI (r= 0.71, p< 0.0001) while a negative significant correlation between peak VO₂ and BMI (r= -024,p=0.0425) was deduced. Similarly, a negative correlation was evident between BSA and BMI (r= -0.46, p=0.0002) with a positive correlation between WtHR and BSA (r= 0.30,p=0.0188). Grip strength performance positively correlated with BSA (r= 0.58, p< 0.0001) whereas peak VO₂ showed a significant negative correlation with WtHR (r= -026,p=0.043). There was also a positive significant correlation between grip strength performance and peak VO₂ (r= 0.37, p=0.0033) Conclusion The study determined the relationships of grip strength performance and peak VO₂, with the body composition indices in order to provide an overview of the mortal risks of an individual which might mediate the prognosis. Based on the relative independence of BSI with peak VO₂ and grip strength performance, the unification of these parameters can help assess the overall health of an individual.

Physical Fitness Among Adolescents Who are Hispanic With Overweight or Obesity

PURPOSE

To describe cardiorespiratory, strength, muscular endurance, and flexibility fitness outcomes in a sample of adolescents who are Hispanic aged 11 to 15 years with overweight or obesity, stratified by age and sex.

METHODS

The sample included 280 adolescents (mean age: 13.0 ± 0.83 years, mean body mass index percentile: 94.6). Anthropometric measures included height, weight, body mass index percentile, and waist and hip circumference. Fitness measures included handgrip strength, sit-ups in 60 seconds, sit-and-reach test, and 6-minute walk test. We report mean scores for each fitness outcome measure and correlation coefficients with anthropometric measures.

RESULTS

Mean handgrip was 23.7 ± 6.48 kg, sit-and-reach test was 25.3 ± 8.13 cm, average sit-ups in 60 seconds were 19.4 ± 9.28, and 6-minute walk distance was 1960 ± 271 ft. Males outperformed females in all tests except sit-and-reach test.

DISCUSSION

Compared with published fitness values of healthy weight adolescents, our sample of adolescents who are Hispanic with overweight/obesity living in southern Florida is unconditioned in terms of cardiorespiratory fitness, strength, muscular endurance, and flexibility.

Association between serum copper, zinc and their ratio and handgrip strength among adults: a study from National Health and Nutrition Examination Survey (NHANES) 2011-2014

Evidence for the association between serum copper and zinc status and handgrip strength is very limited only in several observational studies with study participants of specific population or a narrower age range. The aim of this study was to evaluate the association between serum copper, zinc and their ratio and handgrip strength in the general population. This study included adult participants aged 20-80 years with complete data of serum copper and zinc status and handgrip strength from NHANES 2011-2014. Handgrip strength was calculated as the average of the maximum measure obtained in each hand with a grip strength dynamometer and corrected using BMI. Serum copper and zinc levels were measured using inductively coupled plasma dynamic reaction cell mass spectrometry, and their ratios were calculated. The multivariable linear regression and restricted cubic spline models were used. Serum copper level was inversely associated with BMI-corrected handgrip strength, and the beta coefficients (95% confidence intervals) comparing the second, third, and fourth to the lowest quartiles of serum copper level were - 0.17 kg (- 0.26; - 0.08), - 0.22 kg (- 0.32; - 0.13), and - 0.36 kg (- 0.44; - 0.28), respectively (P for trend < 0.001). Non-linear association was detected between serum copper level and BMI-corrected handgrip strength (P < 0.01). Consistent with serum copper, serum copper/zinc ratio was inversely associated with BMI-corrected handgrip strength. However, no significant associations were observed between serum zinc level and BMI-corrected handgrip strength (all P > 0.05). Higher serum copper level and copper/zinc ratios were significantly associated with lower handgrip strength. Further research is needed to address related issues.

Seven-month wintertime supplementation of 1200 IU vitamin D has no effect on hand grip strength in young, physically active males: A randomized, controlled study

Background

Study Design

Methods

Results

Conclusion

C-Reactive Protein Is Associated with Physical Fitness in Breast Cancer Survivors

Background: Physical fitness (PF) is an expression of the physiological functioning of multiple body components. PF is an important prognostic factor in terms of cardiovascular mortality, cancer mortality, and all-cause mortality. PF has been related to some biomarkers in the general population but not in breast cancer survivors (BCS). Purpose: To evaluate the effects of PF on biomarkers potentially related to physical activity (PA) in a sample of BCS. Methods: Cross-sectional study. A total of 84 BCS (mean age 54) who had finished their treatment were recruited. Different components of PF were evaluated, namely body composition (anthropometry), cardiorespiratory fitness (one-mile walk test), muscular (handgrip and sit-to-stand timed test), and motor (gait speed) components. Sexual hormones, inflammation, and insulin resistance biomarkers were measured. Results: C-Reactive Protein (CRP) was associated with every component of physical fitness: cardiorespiratory fitness (p-value = 0.002), muscular (sit-to-stand timed test, p-value = 0.002) and motor (gait speed, p-value = 0.004) components, and body composition (body mass index, p-value = 0.003; waist, p-value < 0.000; and waist-to-hip index, p-value = 0.012). CRP also was associated with “poor physical condition,” a constructed variable that encompasses all components of physical fitness (p-value < 0.001). Insulin was associated with cardiorespiratory fitness and gait speed (p-values = 0.002 and 0.024, respectively). Insulin-like Growth Factor-1 was negatively associated with waist perimeter and waist-to-hip ratio. Conclusions: CRP can also be considered an indicator of poor PF in BCS. Implications for cancer survivors: in case of elevation of CRP indicating cardiovascular risk, health professionals should recommend lifestyle changes to improve BCS physical condition.

Cardiopulmonary and muscular effects of different doses of high-intensity physical training in substance use disorder patients: study protocol for a block allocated controlled endurance and strength training trial in an inpatient setting

INTRODUCTION

Patients with substance use disorder (SUD) have high prevalence of lifestyle-related comorbidities. Physical exercise is known to yield substantial prophylactic impact on disease and premature mortality, and there seems to be an inverse association between physical fitness and adverse health outcomes. High-intensity training is regarded as most effective for improving physical fitness, but less is known concerning the ideal training dose necessary to achieve clinically relevant effects in these patients. The aim of this study is to compare the effect of low-dose and high-dose, high-intensity training, on physical fitness in patients diagnosed with SUD.

METHODS AND ANALYSIS

This study will recruit 40 in-patients of mixed genders, aged 18-70 years. Participants will be block allocated to low-dose or high-dose training, encompassing 24 high-intensity interval and maximal strength training sessions (3/week × 8 weeks). After a 10 min warm-up, the low-dose group will perform 1×4 min intervals at ⁓90% of maximal heart rate and 2×4 repetitions strength training at ⁓90% of 1 repetition maximum. The high-dose group will perform 4×4 min intervals at ⁓90% of maximal heart rate and 4×4 repetitions strength training at ⁓90% of 1 repetition maximum. Clinical measurements and physical tests will be conducted at baseline, midway and on completion and a questionnaire on physical activity will be administered at baseline.

ETHICS AND DISSEMINATION

This protocol is in accordance with the Standard Protocol Items: Recommendations for Interventional Trials statement. All participants will sign a written informed consent. The Regional Committee of Medical Research Ethics, Norway has approved the study. A study of this kind is warranted, and the results will be published in an open access journal to ensure public access, and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT04065334.

Frailty and risk of cardiovascular disease and mortality

Background

Prospective cohort studies suggest that frailty is associated with an increased risk of incident cardiovascular disease (CVD) morbidity and mortality, but their mechanistic and developmental relations are not fully understood. We investigated whether frailty predicted an increased risk of incident nonfatal and fatal CVD among community-dwelling older adults.

Methods

A population cohort of 5015 participants aged 55 years and above free of CVD at baseline was followed for up to 10 years. Pre-frailty and frailty were defined as the presence of 1–2 and 3–5 modified Fried criteria (unintentional weight loss, weakness, slow gait speed, exhaustion, and low physical activity), incident CVD events as newly diagnosed registered cases of myocardial infarction (MI), stroke, and CVD-related mortality (ICD 9: 390 to 459 or ICD-10: I00 to I99). Covariate measures included traditional cardio-metabolic and vascular risk factors, medication therapies, Geriatric Depression Scale (GDS), Mini-Mental State Exam (MMSE), and blood biomarkers (haemoglobin, albumin, white blood cell counts and creatinine).

Results

Pre-frailty and frailty were significantly associated with elevated HR = 1.26 (95%CI: 1.02–1.56) and HR = 1.54 (95%CI:1.00–2.35) of overall CVD, adjusted for cardio-metabolic and vascular risk factors and medication therapies, but not after adjustment for GDS depression and MMSE cognitive impairment. The HR of association between frailty status and both CVD mortality and overall mortality, however, remained significantly elevated after full adjustment for depression, cognitive and blood biomarkers.

Conclusion

Frailty was associated with increased risk of CVD morbidity and especially mortality, mediated in parts by traditional cardio-metabolic and vascular risk factors, and co-morbid depression and associated cognitive impairment and chronic inflammation. Given that pre-frailty and frailty are reversible by multi-domain lifestyle and health interventions, there is potential benefits in reducing cardiovascular diseases burden and mortality from interventions targeting pre-frailty and early frailty population.

Weak Hand Grip Strength Is Associated with Alexithymia in Outpatients in a Mexican Population

Hand grip strength has been considered as a possible marker for metabolic and psychiatric disease. To date, however, no research has focused on the association between alexithymia and hand grip strength. The objective of the present study was to investigate the correct association between hand grip strength and alexithymia. A cross-sectional study was carried out in Comalcalco, Tabasco, México. A total of 246 individuals were included. Hand grip strength was evaluated in the dominant hand using a Takei^® portable digital dynamometer. Alexithymia was measured using the Toronto Alexithymia Scale (TAS-20). Two linear regression models adjusted by confounders were used to determine the association between alexithymia and hand grip strength. The rate for positive alexithymia was 39.0% (n = 94). Individuals with alexithymia showed a weaker hand grip strength than the comparison group (t = 2.4, 244 df, p = 0.01). Individuals with alexithymia had significantly reduced levels of hand grip strength (β = −0.39 ± 0.14; p = 0.006); after additional adjustment for clinical variables, decreased hand grip strength remained (β = 8.00 ± 1.86; p ≤ 0.001). Our results suggest that a decrease in hand grip strength could be associated with alexithymia. This measurement could be useful as a predictive marker for the identification of alexithymia in Mexican individuals who attend outpatient clinics.

Handgrip Strength-Related Factors in a Colombian Hypertensive Population: A Cross-Sectional Study

(1) Background: This study determined the factors associated with manual grip strength in people with high blood pressure (HBP); (2) Methods: 219 subjects participated in this cross-sectional study, which evaluated muscle strength (manual dynamometer), sociodemographic factors, clinical characteristics, level of physical activity (International Physical Activity Questionnaire-IPAQ score), and depression (Zung's Depression Self-Rating Scale); (3) Results: The bivariate analysis found that handgrip strength in people with HPB was associated with sex (p = 0.000), age (p = 0.000), ethnicity (p = 0.019), smoking habits (p = 0.037), alcohol consumption (p = 0.004), diastolic blood pressure (p = 0.012), weight (p = 0.000), height (p = 0.000), measurement of waist circumference (p = 0.002), depression (p = 0.041), and IPAQ score (p = 0.000). Regardless of being male or female, handgrip strength was associated with age (p = 0.009), IPAQ (p = 0.000), weight (p = 0.038), height (p = 0.000), DPB units (p = 0.043), and depression (p = 0.020). The multivariate generalized linear gamma regression model showed that the coefficient with the greatest weight, regardless of sex, was age (p = 0.043), level of physical activity (24% more at high level than at low level, p = 0.031), and depression (moderate/severe depression level) associated with lower handgrip strength (p = 0.025); (4) Conclusions: Handgrip strength showed an association with level of physical activity, age, and level of depression in a middle-aged population with HBP.

Relationships of sex hormones with muscle mass and muscle strength in male adolescents at different stages of puberty

This study analysed the associations of sex steroids with fat-free mass (FFM) and handgrip strength in 641 Chinese boys. Serum total testosterone (TT) and oestradiol were measured by chemiluminescence immunoassay. Free testosterone (FT) and oestradiol were calculated. FFM and handgrip strength were measured by bioelectrical impedance analysis and a hand dynamometer, respectively. Generalised additive models and multiple linear regression were used to explore the relationships. A subgroup analysis was conducted in early-mid pubertal and late-post pubertal groups. Age, height, weight, physical activity, intake of dietary protein and/or stage of puberty were adjusted. TT and FT were positively related to FFM and handgrip strength, with a curvilinear relationship being detected for handgrip strength (p<0.050). This curvilinear relationship was only observed in the late-post pubertal group, suggesting a potential threshold effect (FT>11.99ng/dL, β = 1.275, p = 0.039). In the early-mid pubertal group, TT and/or FT were linearly or near-linearly related to FFM or handgrip strength (β = 0.003-0.271, p<0.050). The association between FT and FFM was stronger than that in the late-post pubertal group. This study found that serum T had different associations with muscle parameters in Chinese early-mid pubertal and late-post pubertal boys. In the late-post pubertal boys, serum T was curvilinearly related to muscle strength with a threshold effect and its link with muscle mass was weaker.

Impact of Synchronous Online Physical Education Classes Using Tabata Training on Adolescents during COVID-19: A Randomized Controlled Study

This study aimed to investigate the effects of online physical education classes, using Tabata training, on middle school students’ physical fitness. Fifty-four adolescents were randomly assigned to either the asynchronous online class group (AOCG, n = 24, age: 15.8 ± 0.4 years) or the synchronous online class group (SOCG, n = 24 age: 15.9 ± 0.3 years). The online physical education class lasted two days per week for 10 weeks. Recorded video lectures were conducted for the AOCG, and Tabata training for the SOCG, as real-time lecture methods. Baseline and post-online physical education class measures included muscular strength, muscular endurance, flexibility, balance, and cardiorespiratory fitness tests. The results showed that the synchronous online physical education class had a positive effect on the improvement of muscle mass, ankle strength (dorsiflexion), hip strength (abduction, flexion, extension, and external rotation), knee strength (extension and flexion), and balance (Y-balance test) in adolescents. These findings suggest that the physical fitness of adolescents can be sufficiently improved through appropriate online physical education class methods. Further research should focus on developing and evaluating different types of exercises for synchronous online physical education classes as a precautionary measure for the second wave of COVID-19.

Genetic Risk, Muscle Strength, and Incident Stroke: Findings From the UK Biobank Study

OBJECTIVE

To examine the associations of muscle strength and genetic risk for stroke with stroke incidence.

PARTICIPANTS AND METHODS

We included 284,767 white British participants of UK Biobank without genetic relatedness and stroke or myocardial infarction at baseline between March 13, 2006, and October 1, 2010. Genetic risk was assessed with polygenic risk scores, calculated by summing the risk-increasing alleles, weighted by the effect estimates. Muscle strength was assessed through grip strength tests by hand dynamometers. Incidence of overall (n= 4008), ischemic (n= 3031), and hemorrhagic (n=1073) stroke was adjudicated during 11.5-year follow-up.

RESULTS

Compared with the bottom muscle strength tertile, hazard ratios (95% CI) of stroke were 0.81 (0.75 to 0.87) and 0.76 (0.71 to 0.82) for the middle and top muscle strength tertiles, respectively, after adjustment for confounders and genetic risk; higher genetic risk was independently associated with higher stroke incidence. Stroke hazards for the top muscle strength tertile were consistently lower across genetic risk strata, with no evidence of interaction. Compared with individuals with high muscle strength and low genetic risk, stroke hazards were higher for individuals who had medium or high genetic risk combined with low or medium muscle strength but not for those who had medium genetic risk but high muscle strength. Associations were similar for ischemic and hemorrhagic stroke (although CIs were inconclusive for some of the associations).

CONCLUSION

Higher muscle strength was associated with lower stroke incidence in all individuals, including those with high genetic susceptibility. The increased genetic risk of overall and ischemic stroke was partly attenuated through increased muscle strength.

The relationship between serum folate and grip strength in American adults

We used data from NHANES to explore the associations between serum folate and grip strength, and found that high levels of serum folate were associated with increased grip strength among females rather than males. It is recommended to maintain a proper level of serum folate, especially in women.

PURPOSE

Associations and dose-response relationships between serum total folate, 5-methyltetrahydrofolate, and grip strength in general adults were unknown. Thus, we conducted this analysis for further exploration.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) database of 2011-2014 cycle were used. The independent variables including serum total folate, combined total folate (total folate plus Mefox), and 5-methyltetrahydrofolate. The dependent variable was BMI-corrected grip strength. Linear regression and the restricted cubic splines were used in our analyses.

RESULTS

A total of 9079 adults aged over 20 years were included. In multivariate-adjusted model 2, compared with quartile (Q) 1, grip strength increased in Q3 of combined total folate and total folate, and the weighted β values with 95% confidence intervals (CIs) of grip strength were 0.06 (0.01, 0.12) and 0.06 (0.00, 0.10) for combined total folate and total folate, respectively. In the stratified analysis by gender, positive relationships between combined total folate, total folate, and 5-methyltetrahydrofolate and grip strength were found only in females, with β (95% CIs) of 0.07 (0.02, 0.12), 0.07 (0.03, 0.12), and 0.09 (0.05, 0.13) for combined total folate, total folate, and 5-methyltetrahydrofolate in Q4, respectively. Non-linear positive dose-response relationships between serum folate and grip strength were also found only in females, not in males.

CONCLUSION

Our study suggested a positive association between serum folate and grip strength, while this positive association was only found in females; besides, the dose-response relationships were in a non-linear trend. Thus, it is recommended to maintain a proper serum folate level to keep better muscle strength, especially for women.

Secular trends in health-related physical fitness among 11-14-year-old Croatian children and adolescents from 1999 to 2014

The main purpose of the study was to analyze secular trends of health-related physical fitness in 7–14-year-old Croatian children and adolescents from 1999 and 2014. In this observational cross-sectional study, we recruited 5077 children and adolescents between ages 11 and 14 (50.8% girls) from five primary schools located in the capital city of Zagreb. Physical fitness performance was tested from 1999 until 2014. Physical fitness performance included: (1) body-mass index (measure of body size), (2) standing broad jump (measure of lower-body power), (3) polygon backwards (measure of general coordination and agility), (4) sit-ups in 60 s (measure of upper-body strength), (5) sit-and-reach test (measure of flexibility) and (6) 6-min run test (measure of cardiorespiratory fitness). Boys performed better in all physical fitness tests, except for sit-and-reach test (p < 0.001). In boys, between 1999 and 2014, body size, upper-body strength and coordination/agility increased, while flexibility, lower-body power and cardiorespiratory fitness decreased. During the same period, girls experienced an increase in body size, lower-body power, upper-body strength, coordination/agility and flexibility, while cardiorespiratory fitness decreased. This study shows that cardiorespiratory fitness, flexibility and coordination/agility decrease, while upper-body strength increases in both sexes. These findings should serve as an avenue for national monitoring system to screen and track biological development in children and adolescents.

Temporal Trends in the Standing Broad Jump Performance of 10,940,801 Children and Adolescents Between 1960 and 2017

BACKGROUND

The standing broad jump (SBJ) is an excellent functional measure of explosive lower-body strength that is significantly related to health among children and adolescents.

OBJECTIVES

The aim of this study was to estimate national (country-level) and international (pooled global data) temporal trends in SBJ performance for children and adolescents, and to examine the relationships between national trends in SBJ performance and national trends in health-related and socioeconomic/demographic indicators.

METHODS

Data were obtained from a systematic search of studies reporting temporal trends in SBJ performance for 9- to 17-year-olds, and by examining national fitness datasets. Sample-weighted regression models estimated trends at the study/dataset-country-sex-age level, with national and international trends estimated by a post-stratified population-weighting procedure. Pearson's correlations quantified relationships between national trends in SBJ performance and national trends in health-related and socioeconomic/demographic indicators.

RESULTS

Data from 34 studies/datasets were extracted to estimate trends for 10,940,801 children and adolescents from 24 high-, 4 upper-middle-, and 1 low-income countries between 1960 and 2017. Collectively, there was a negligible (per decade) improvement in SBJ performance of 1.73 cm (95% CI 1.71-1.75), 0.99% (95% CI 0.97-1.01) or a standardized effect size of 0.07 (0.07-0.07) over the entire period, with the rate of improvement steady from the 1960s to the 1980s, slowing in the 1990s, before declining. Sex- and age-related temporal differences were negligible. Trends differed between countries, with most countries experiencing declines. National trends in SBJ performance were not significantly related to national trends in health-related and socioeconomic/demographic indicators.

CONCLUSIONS

SBJ performance of children and adolescents has declined since 2000 (at least among most of the countries in this analysis) and is suggestive of a modern decline in functional explosive lower-body strength. Growing recognition of the importance of muscular fitness as a marker of population health highlights the need for continued tracking of temporal trends in SBJ, especially among low- and lower-middle-income countries for which temporal data are lacking.

PROSPERO REGISTRATION NUMBER

CRD42013003657.

Cardiorespiratory fitness, muscular strength, and obesity in adolescence and later chronic disability due to cardiovascular disease: a cohort study of 1 million men

Aims

Cardiorespiratory fitness, muscular strength, and obesity in adulthood are risk factors for cardiovascular disease (CVD). However, little is known regarding the associations of these risk factors, already in adolescence, with later disability due to chronic CVD. Hence, we investigated associations of cardiorespiratory fitness, muscular strength, and body mass index (BMI) in adolescence with later chronic disability due to specific causes of CVD disability (i.e. cerebrovascular disease, ischaemic heart disease and heart failure).

Methods and results

This population-based cohort study included 1 078 685 male adolescents (16–19 years) from the Swedish military conscription register from 1972 to 1994. Cardiorespiratory fitness (bicycle ergometer test), muscular strength (knee extension strength), and BMI were measured during the conscription examination. Information about disability pension due to CVD was retrieved from the Social Insurance Agency during a mean follow-up of 28.4 years. Cardiorespiratory fitness was strongly and inversely associated with later risk of chronic CVD disability for all investigated causes. The association was particularly strong for ischaemic heart diseases (hazard ratio 0.11, 95% confidence interval 0.05–0.29 for highest vs. lowest fitness-quintiles). Furthermore, overweight/obesity were associated with CVD disability for all investigated causes. Conversely, associations of muscular strength with CVD disability were generally weak.

Conclusions

This study provides evidence for associations between low levels of cardiorespiratory fitness and obesity with later risk of chronic disability due to CVD. Preventive actions may begin at young ages and include promotion of cardiorespiratory fitness and healthy body weight.

Secular trends in muscular fitness from 1983 to 2014 among Slovenian children and adolescents

Low physical fitness has been found to be associated with many chronic diseases and medical conditions. Knowledge of secular trends in physical fitness is important to initiate countermeasures for addressing negative trends. The aim of this study was to analyze secular trends in health-related muscular fitness in Slovenian children and adolescents between 1983 and 2014. Data were collected as part of "The Analysis of Children's Development in Slovenia (ACDSi)" study in 1983, 1993/94, 2003/04, and 2013/14. Anthropometry (body weight, height, BMI, and triceps skinfold) and muscular fitness (standing long jump, bent-arm hang, and sit-ups 60 s test) of 18730 (9168 female) students from primary and secondary schools were recorded. The secular trend was analyzed considering anthropometry. The results showed that anthropometric measures had an increasing trend and overall muscular fitness had a decreasing trend. Leg muscle power decreased over the decades in all age groups (relative difference between -1.5% and -2.6%), being more pronounced in boys. Arm muscle strength decreased in two younger age groups (range -21.1% to -42.7%, 6-10, and 11-14 years), but not in the oldest group (15-19 years), where the increase occurred in both genders (0.4% to 9.3%). In terms of decades, the largest negative changes (-30.1%) occurred from 1993/94 to 2003/04 and the smallest changes (-4.2%) from 2003/04 to 2013/14. The overall trend in repetitive core strength surprisingly increased (1.1% to 18.3%). There is a need to promote healthy lifestyles, raise parental awareness and use all government resources to redirect the negative trend in physical fitness.

Home-Measured Blood Pressure Is Associated with Handgrip Strength in Patients with Type 2 Diabetes: The KAMOGAWA-HBP Study

The association between blood pressure measured at home and handgrip strength in patients with diabetes has not been investigated. Therefore, in this study, we aimed to assess this association among patients with type 2 diabetes. In this cross-sectional study, 157 patients with type 2 diabetes underwent muscle tests and morning and evening blood-pressure measurements at home in triplicate for 14 consecutive days throughout the study period. Univariate and multivariate regression analyses were conducted to analyze the relationship between home blood-pressure parameters and handgrip strength. The average age and hemoglobin A1c of the patients were 70.5 years and 7.1%, respectively. Morning diastolic blood pressure of [β (95% confidence interval; CI): 0.20 (0.03, 0.37)] was associated with handgrip strength in men, while morning systolic blood pressure of [-0.09 (-0.15, -0.04)], morning pulse pressure of [-0.14 (-0.21, -0.08)], and evening pulse pressure of [-0.12 (-0.19, -0.04)] were associated with handgrip strength in women. Home-measured blood pressure was associated with handgrip strength. Sex differences were found in the relationship between home blood-pressure parameters and handgrip strength.

Relevance of Physical Fitness and Cardiovascular Disease Risk

BACKGROUND

This study explored the relationship between fitness performance, in terms of muscular endurance and cardiorespiratory fitness (CRF), and cardiovascular disease (CVD) risk.

METHODS AND RESULTS

The study was performed on 51,500 eligible participants from the Republic of China Armed Forces. Participants were divided into 4 groups (obese or non-obese males and females). Correlations between the Framingham risk score of coronary artery disease (FRS-CAD) and physical fitness (evaluated using 2-min push-ups, 2-min sit-ups, and 3,000-m non-weight-bearing running tests) were calculated using univariate and multivariate linear regression, as well as an extended model that adjusted for covariates. In males, regardless of obesity status, there were significant negative correlations between quartiles of fitness performance and the FRS-CAD (P<0.001) in the unadjusted and adjusted models, except for the sit-up test in the model adjusted for age, serum uric acid, hemoglobin, creatinine, current drinking, betel nut chewing, and running test speed. FRS-CAD was lower for higher quartiles of physical fitness (P for trend <0.001) in male participants. However, no significant relationship between fitness performance and FRS-CAD was observed in females, regardless of obesity status.

CONCLUSIONS

The findings highlighted a substantial association between fitness performance and FRS-CAD, especially in adult males. Muscular endurance and CRF may be a convenient risk evaluation tool for future CVD risk in the general, healthy, young to middle-aged male population in Taiwan.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Interactions between Growth of Muscle and Stature: Mechanisms Involved and Their Nutritional Sensitivity to Dietary Protein: The Protein-Stat Revisited

Childhood growth and its sensitivity to dietary protein is reviewed within a Protein-Stat model of growth regulation. The coordination of growth of muscle and stature is a combination of genetic programming, and of two-way mechanical interactions involving the mechanotransduction of muscle growth through stretching by bone length growth, the core Protein-Stat feature, and the strengthening of bone through muscle contraction via the mechanostat. Thus, growth in bone length is the initiating event and this is always observed. Endocrine and cellular mechanisms of growth in stature are reviewed in terms of the growth hormone-insulin like growth factor-1 (GH-IGF-1) and thyroid axes and the sex hormones, which together mediate endochondral ossification in the growth plate and bone lengthening. Cellular mechanisms of muscle growth during development are then reviewed identifying (a) the difficulties posed by the need to maintain its ultrastructure during myofibre hypertrophy within the extracellular matrix and the concept of muscle as concentric "bags" allowing growth to be conceived as bag enlargement and filling, (b) the cellular and molecular mechanisms involved in the mechanotransduction of satellite and mesenchymal stromal cells, to enable both connective tissue remodelling and provision of new myonuclei to aid myofibre hypertrophy and (c) the implications of myofibre hypertrophy for protein turnover within the myonuclear domain. Experimental data from rodent and avian animal models illustrate likely changes in DNA domain size and protein turnover during developmental and stretch-induced muscle growth and between different muscle fibre types. Growth of muscle in male rats during adulthood suggests that "bag enlargement" is achieved mainly through the action of mesenchymal stromal cells. Current understanding of the nutritional regulation of protein deposition in muscle, deriving from experimental studies in animals and human adults, is reviewed, identifying regulation by amino acids, insulin and myofibre volume changes acting to increase both ribosomal capacity and efficiency of muscle protein synthesis via the mechanistic target of rapamycin complex 1 (mTORC1) and the phenomenon of a "bag-full" inhibitory signal has been identified in human skeletal muscle. The final section deals with the nutritional sensitivity of growth of muscle and stature to dietary protein in children. Growth in length/height as a function of dietary protein intake is described in the context of the breastfed child as the normative growth model, and the "Early Protein Hypothesis" linking high protein intakes in infancy to later adiposity. The extensive paediatric studies on serum IGF-1 and child growth are reviewed but their clinical relevance is of limited value for understanding growth regulation; a role in energy metabolism and homeostasis, acting with insulin to mediate adiposity, is probably more important. Information on the influence of dietary protein on muscle mass per se as opposed to lean body mass is limited but suggests that increased protein intake in children is unable to promote muscle growth in excess of that linked to genotypic growth in length/height. One possible exception is milk protein intake, which cohort and cross-cultural studies suggest can increase height and associated muscle growth, although such effects have yet to be demonstrated by randomised controlled trials.

Increased dairy product consumption as part of a diet and exercise weight management program improves body composition in adolescent females with overweight and obesity-A randomized controlled trial

BACKGROUND

Exercise can improve body composition in adolescents and adults with overweight/obesity. Consumption of dairy foods, as part of a healthy lifestyle program, can also promote favourable body composition changes in adults with overweight/obesity. However, the few studies examining these combined effects on body composition in adolescents are inconclusive.

OBJECTIVE

To determine whether increased dairy product consumption, as part of a lifestyle modification program featuring exercise training and dietary guidance promotes favourable body composition changes in adolescent females with overweight/obesity.

METHODS

Fifty-four participants (age: 14.8 ± 2.2y; BMI percentile: 95th ± 6) assigned to three groups completed the study. There were two experimental groups: recommended dairy (RDa; n = 24) and low dairy (LDa; n = 22), and a no-intervention control group (Con; n = 8). RDa and LDa participated in a 12-week, eucaloric, lifestyle modification intervention consisting of mixed-mode exercise (3x/week), and nutritional counselling. RDa was provided 4 servings/day of dairy foods, while LDa and Con maintained habitually low intakes (0-2 servings/day). Body weight/composition, waist/hip circumference, cardiovascular fitness and food intake were assessed at weeks 0 and 12.

RESULTS

Weight did not significantly change in any group. RDa significantly decreased fat mass (FM) and increased lean mass (LM) more than LDa and Con (FM: -1.3 ± 2.1 kg, -1.1 ± 2.0 kg, 0.8 ± 1.8 kg; LM: 1.5 ± 1.9 kg, 0.7 ± 1.6 kg, 0.5 ± 1.4 kg, respectively). LDa also significantly decreased FM and increased LM more than Con (P < .005; all interactions).

CONCLUSION

The inclusion of dairy foods in the diet of adolescent females with overweight/obesity, as part of a diet and exercise intervention, favourably improves body composition in the absence of weight loss.

Combined exercise training improves blood pressure at rest and during exercise in young obese prehypertensive men

BACKGROUND

Regular exercise is an effective intervention to yield health-related benefits, though an optimal dosage and its ability to improve hemodynamics at rest and during exercise are yet to be established. Therefore, this study aimed to assess the effects of a combined (aerobic and resistance) exercise training program on hemodynamic variables at rest and during exercise in young obese prehypertensive men.

METHODS

Twenty obese prehypertensive men (age: 20±1.2 years) were randomly assigned to either the combined exercise training group (CBT, N.=10), or the control group (CON, N.=10). The CBT underwent a supervised combined exercise training program incorporating four 60-min sessions per week over 12 weeks, whereas the CON remained in habitual activities. We assessed BP, peak oxygen consumption (V̇O<inf>2peak</inf>), body composition, muscular strength, and hemodynamic responses to incremental exercise at baseline and post intervention.

RESULTS

The study revealed significant improvements in resting systolic blood pressure (SBP) of 4.3% (P<0.05), and rate-pressure product (RPP) of 11.3% (P<0.05) following 12 weeks of training. Significant reductions in SBP and RPP during exercise were also present at every exercise intensity. Moreover, the CBT training improved V̇O<inf>2peak</inf> by 18.2% (P<0.01), upper body muscle strength by 15.1% (P<0.01), and reduced body fat (P<0.01).

CONCLUSIONS

The CBT is effective in reducing SBP and myocardial oxygen demand at rest and during exercise. It can also improve cardiorespiratory fitness, muscular strength, and reduce body fat; especially in terms of abdominal obesity. Thus, we suggest the use of the CBT program for the prevention of future hypertension in young obese prehypertensive men.

Association of Body Shape Index (ABSI) with Hand Grip Strength

Hand grip is a leading measure of muscle strength and general health, yet its association with body shape is not well characterized. Here, we examine correlations between grip strength, a body shape index (ABSI), and body mass index (BMI) in the 2011-2014 United States National Health and Nutrition Examination Survey cohorts. Grip strength was found to correlate negatively with ABSI (though positively with BMI), suggesting that those with a more central body profile tend to be weaker than others with the same weight. Individuals with low grip strength, as well as those with high ABSI, were more likely to die during follow up, whereas there was no association of BMI with mortality hazard. Transforming the grip strength, ABSI, and BMI by taking their logarithm prior to standardization did not meaningfully change the associations seen. These findings suggest that combining anthropometrics (ABSI, BMI) with grip strength may better identify individual mortality hazard in research studies and clinical practice.

The Inverse Association of Muscular Strength with Carotid Intima-media and Extra-media Thickness in Women

The purpose of this study was to determine the relationship between strength and atherosclerotic cardiovascular disease (CVD) risk in young women. Carotid intima-media thickness (IMT) and extra-media thickness (EMT) were used as measures of subclinical atherosclerosis and CVD risk. Muscular strength, IMT, and EMT were measured in 70 young women (mean age=21±4 years). Strength was determined using a handgrip dynamometer and expressed relative to body mass. IMT and EMT were measured using ultrasonography of the left common carotid artery. Objectively measured moderate-vigorous physical activity (MVPA) was assessed with accelerometry. Higher relative handgrip strength was associated with lower IMT (r=-0.23; p<0.05) and lower EMT (r=-0.27; p<0.05). Associations between relative handgrip strength and IMT (r=-0.24) as well as EMT (r=-0.25) remained significant after adjusting for potential confounders including traditional CVD risk factors and MVPA (p<0.05). These results show that there is an inverse association between handgrip strength with carotid IMT and EMT in young women. Muscular strength may reduce CVD risk in young women via favorable effects on subclinical carotid atherosclerosis independent of physical activity.

Sarcopenic obesity in ageing: cardiovascular outcomes and mortality

Obesity is a major public health issue with prevalence increasing worldwide. Obesity is a well-established risk factor for CVD and mortality in adult populations. However, the impact of being overweight or obese in the elderly on CVD and mortality is controversial. Some studies even suggest that overweight and obesity, measured by BMI, are apparently associated with a decreased mortality risk (known as the obesity paradox). Ageing is associated with an increase in visceral fat and a progressive loss of muscle mass. Fat mass is positively associated and lean mass is negatively associated with risk of mortality. Therefore, in older adults BMI is not a good indicator of obesity. Sarcopenia has been defined as the degenerative loss of muscle mass, quality and strength with age and is of major concern in ageing populations. Sarcopenia has previously been associated with increased risks of metabolic impairment, cardiovascular risk factors, physical disability and mortality. It is possible for sarcopenia to co-exist with obesity, and sarcopenic obesity is a new class of obesity in older adults who have high adiposity levels together with low muscle mass, quality or strength. Therefore, sarcopenia with obesity may act together to increase their effect on metabolic disorders, CVD and mortality. This review will discuss the available evidence for the health implications of sarcopenic obesity on CVD and mortality in older adults.

Association of biological maturation with the development of motor competence in Austrian middle school students-a 3-year observational study

BACKGROUND

Motor competence is an important component in the facilitation of an active lifestyle and is influenced by environmental and biological constraints. Biological maturation has been shown to affect participation in various forms of physical activity (PA) and sports but information on the association with motor competence and motor development remains limited.

METHODS

A total of 212 (59% male) Austrian middle school students (10.8±0.5 years) were followed over 3 years. Participants completed annual anthropometric measurements along with the German motor test (Deutscher Motorik Test, DMT6-18) during a physical education lesson. Biological maturation was determined based on the estimated age at peak height velocity (APHV), as this has been shown to coincide with the onset of puberty.

RESULTS

Earlier maturation was associated with higher body weight and lower motor competence in boys and girls. Cross-sectional associations between motor competence and biological maturation, however, were limited after adjusting for body weight. Longitudinal results showed a more pronounced weight gain and impaired development of motor competence late maturing boys. In girls, weight gain was more pronounced with early maturation but this did not affect the development of motor competence. It was further shown that endurance capacity already declined in this cohort while agility increased.

CONCLUSIONS

The results of this study confirm the previously reported association between biological maturation and body weight, which also affects motor competence. Nevertheless, late maturing boys appear to be at a greater risk for excess weight gain, which negatively affects the development of motor competence during early adolescence. In girls, the association between weight change and development of motor competence was less clear. Of additional concern is the decline in cardiorespiratory fitness already during early adolescence as low cardiorespiratory fitness is associated with an increased risk for various chronic diseases later in life.

Physical Fitness and Anthropometric Values Among Lithuanian Primary School Children: Population-Based Cross-Sectional Study

Emeljanovas, A, Mieziene, B, Cesnaitiene, VJ, Fjortoft, I, and Kjønniksen, L. Physical fitness and anthropometric values among Lithuanian primary school children: population-based cross-sectional study. J Strength Cond Res 34(2): 414-421, 2020-The purpose of the current study was to derive representative reference scores on anthropometric measures and test scores for the musculoskeletal, motor, and cardiorespiratory fitness of Lithuanian primary school children according to age and sex. This cross-sectional design study included 3,456 Lithuanian first- to fourth-grade children from age 6 to 10 years. Physical fitness was measured using a nine-item test battery developed by Fjørtoft et al. The test battery included the following tests: standing broad jump (explosive strength), jumping a distance of 7 m on 2 feet, jumping a distance of 7 m on 1 foot (both tests indicate leg muscle strength), throwing a tennis ball with one hand, and pushing a medicine ball with 2 hands (both tests indicate arm muscle strength). These tests measured musculoskeletal fitness. In addition, there were measures of a 10 × 5-m shuttle run (agility), running 20 m as fast as possible (speed), and climbing wall bars (coordination)-general tests of motor fitness. Reduced 6-minute Cooper test (endurance) measured cardiorespiratory fitness. A Student's t test and analysis of variance were performed to indicate differences between sexes and across age, respectively. The significant differences in mean scores in anthropometric and fitness means indicated that boys had higher scores than girls, and older children scored higher than younger children (p < 0.05). Data on normative sex- and age-specific percentile values (3rd, 10th, 25th, 50th, 75th, 90th, and 97th) for physical fitness tests in Lithuanian primary school children are provided. These data are useful for educational settings, parents, clinicians, sports organizations, and sports clubs in identifying problems or outstanding performance and providing sports programs that develop children's athletic performance.

The value of hand grip strength (HGS) as a diagnostic and prognostic biomarker in congenital heart disease

Background

In patients with congenital heart disease (CHD), there is little data on the diagnostic and prognostic relevance of hand grip strength (HGS) for clinical assignment, while in the general population the loss of muscle strength and mass is an important risk factor in cardiovascular disease which is conversely associated with morbidity and all-cause mortality. This study aimed to assess the degree of muscle dysfunction using HGS as a biomarker in a large group of patients with CHD who often develop muscle dysfunction.

Methods

In total, 385 patients (27.6±13.1 years, 43% female) were included and assigned to 5 diagnostic groups: complex anomalies (n=131), left heart anomalies/aortopathies (n=107), right heart/pulmonary artery anomalies (n=92), primary left to-right-shunts (n=42) and miscellaneous CHD (n=13). Patients with Fontan circulation, chronic cyanosis, morphologic right systemic ventricle, arterial switch operation, or Ebstein's anomaly were analyzed separately. A control group (CG) consisted of 124 healthy individuals (30.1±12.1 years, 42% female). HGS was measured with a Jamar Hydraulic Hand Dynamometer.

Results

HGS was reduced in CHD patients compared to controls (35.2±14.6 versus 43.7±14.4 kg). Most impairments were present in females (26.1±7.6 kg). Patients with cyanosis had lower HGS values compared to acyanotic CHD patients (P=0.03). Patients with left heart lesions had the highest HSG values (40.7±14.7 kg), while patients with primary left-to-right shunt lesions had the lowest HSG values (30.9±11.3 kg). Within specific groups of cardiac anomalies, patients with Fontan circulation showed the lowest (P=0.033) and patients with a morphologic right system ventricle showed higher results (P=0.004). The late mid-term survival was favorable, and 7 patients (1.8%) died in a median interval of 422 days (range, 206-1,824 days) after HGS-testing.

Conclusions

This study provides the most comprehensive data on the use of HGS in CHD to date. Grip strength is an easily applicable, repeatedly usable and a cost-effective diagnostic tool to gain a quick, quantifiable assessment of the patient's current muscle function as an expression of cardiac fitness. Considering the low number of patients who died in the observation period, HGS may not be a suitable tool for survival assessment or identification of patients at risk. However, HGS is well suited to determine muscle function and strength and thereby to identify and to follow-up patients who have an increased cardiovascular risk.

Body Fat Mass and Risk of Cerebrovascular Lesions: The PRESENT (Prevention of Stroke and Dementia) Project

Obesity is known to increase the risk of stroke. It is unclear whether high absolute fat mass (FM) increases the risk of stroke independently. We studied the correlation between FM and silent brain infarction/white matter change (SI/WMC) using brain computed tomography. We selected subjects from the local government health promotion project. We randomly selected a target population that had never been diagnosed with stroke or dementia. FM was measured by bioelectrical impedance analysis (BIA). We divided the subjects into three groups according to the FM (gender-specific tertiles [GTx]). Seven hundred and twenty-two subjects (321 men) between 50 and 75 years of age were recruited. The overall odds ratio (OR) of SI/WMC was 2.23 (95% confidence interval (CI), 1.34-3.71; p = 0.002) times higher in the 37th to 100th percentiles (GT3) than in the first to 32nd percentiles (GT1). When men and women were separated, the OR of GT3 was 1.35 (CI, 0.62-2.94; p = 0.45) in men and 3.2 (CI, 1.60-6.40; p = 0.001) in women. The findings were not found to be statistically significant after adjusting for the well-known stroke risk factors. When the subjects were divided into a high FM (HFMG, GT3) and low FM group (LFMG, GT1 + GT2), the HFMG showed an increased OR of SI/WMC in women. Similar results were seen after adjusted (overall: OR, 1.38; CI, 0.85-2.25, p = 0.198; men: OR, 0.93; CI, 0.422-2.051; p = 0.86; women: OR, 2.02; CI, 1.06-3.86; p = 0.03). The findings suggest that high FM may be an independent risk factor for ischemic stroke among adults free from stroke and dementia, especially in women.

Cardiovascular health metrics, muscle mass and function among Italian community-dwellers: the Lookup 7+ project

Background

Primordial prevention is essential for promoting cardiovascular health and longevity through the so-called seven cardiovascular health metrics (CHMs) (i.e. smoking, body mass index, diet, physical activity, blood pressure, blood glucose and total cholesterol). Measures of muscle mass and function are recognized as powerful predictors of health-related events and survival. Therefore, the present study was undertaken to assess the prevalence and distribution of the seven CHMs and measures of muscle mass and function in an unselected cohort of community-dwellers.

Methods

The Longevity check-up 7+ (Lookup 7+) project is an ongoing cross-sectional survey conducted in unconventional settings (e.g. exhibitions, malls and health promotion campaigns) across Italy. CHMs are assessed through a brief questionnaire and by measurement of standing height, body weight, blood glucose, blood cholesterol and blood pressure. Muscle mass is estimated from calf circumference, whereas muscle strength and function are measured via handgrip strength and chair-stand testing, respectively. Results Analyses were conducted in 6323 community-living adults (mean age: 54 ± 15 years, 57% women) recruited between 1 June 2015 and 30 June 2017. Participants presented on average 4.3 ± 1.3 ideal CHMs, which decreased with age. Only 19.5% of participants met >5 ideal metrics, while 8.3% met <3. All seven ideal metrics were met by 4.7% of enrollees. Muscle mass, strength and function declined progressively with age, starting at 45-50 years. Conclusion Our population showed suboptimal CHMs scores, with very low prevalence of all ideal metrics. The number of ideal metrics decreased progressively with age and so did muscle mass and function.

Muscle fitness and its association with body mass index in children and adolescents aged 7-18 years in China: a cross-sectional study

BACKGROUND

The present study was the first one aimed to investigate the current muscle fitness and its associated factors among children and adolescents in mainland China.

METHODS

From Nov 2013 to Jul 2014, 2283 children and adolescents aged 7-18 were recruited in Hainan and Shaanxi Provinces in China by cross-sectional design. Information on anthropometry and muscle fitness, measured by hand grip strength (GS), vertical jump (VJ) and sit-and-reach (SR), were collected. Analysis of covariance was performed by using general linear regression models to identify the association between BMI and muscle fitness.

RESULTS

The means of GS, VJ and SR in boys were 22.30 ± 11.55 kg, 22.93 ± 6.80 cm and 3.58 ± 7.31 cm, respectively, and in girls were 16.61 ± 6.87 kg, 18.11 ± 4.08 cm and 7.18 ± 5.72 cm, respectively. GS (from 8.26 kg in the 7-8-year-old group to 27.91 kg in the 17-18 group) and SR (from 1.75 cm in the-8-year-old group to 10.12 cm in the 17-18 group) increased with age (both p for trend < 0.001). Boys had higher GS and VJ, but significantly lower SR than girls in each age group (p < 0.001). After adjusting for age, sex, residential areas and study regions, GS increased with elevated BMI (compared with normal weight group, the regression coefficient for thinness and overweight/obesity were - 2.997(95%CI: -3.693 to - 2.301) and 1.220 (95%CI: 0.285 to 2.155), respectively. With the p values less than 0.001 and 0.011, respectively). For VJ, there was no difference found between normal weight group and overweight/obesity group (p = 0.550), but the thinness group had the lowest performance (regression coefficient = - 2.681, 95%CI from - 3.965 to - 1.397, p < 0.001). For SR, compared with normal weight group, the regression coefficients for thinness and overweight/obesity were - 1.313(95%CI: -2.228 to - 0.399) and - 1.623(95%CI: -3.216 to - 0.030) respectively, both p < 0.05.

CONCLUSIONS

Increased body weight may have a positive association with isometric muscle strength measured by grip strength, but a negative one with strength of lifting the body. Sex difference was also found in the performance of flexibility.

Muscle Fitness Cut Points for Early Assessment of Cardiovascular Risk in Children and Adolescents

OBJECTIVES

To study the cross-sectional and longitudinal (2-year follow-up) association between muscle fitness and cardiovascular disease (CVD) risk factors in youth; whether there are muscle fitness cut points associated with CVD risk (cross-sectional); and whether the health-related muscle fitness cut points identified at baseline are associated with CVD risk 2 years later.

STUDY DESIGN

In total, 237 children (110 girls) aged 6-10 years and 274 adolescents (131 girls) aged 12-16 years with complete data were included in the study (10.3% drop out). The handgrip strength and the standing long jump tests were used to assess muscle fitness. CVD risk score was computed with sum of 2 skinfolds, systolic blood pressure, insulin, glucose, triglycerides, and total cholesterol/high density lipoprotein cholesterol.

RESULTS

Muscle fitness at baseline was associated inversely with single CVD risk factors and CVD risk score at baseline and 2-year follow-up (all P < .05). Receiver operating characteristics curve analyses showed a significant discriminating accuracy of handgrip strength in identifying CVD risk in children and adolescents (boys: ≥ 0.367 and ≥0.473; girls: ≥ 0.306 and ≥0.423 kg/kg body mass, respectively, all P < .001). Similarly, the standing long jump cut points for children and adolescents were ≥104.5 and ≥140.5 in boys, and ≥81.5 and ≥120.5 cm in girls, respectively (all P < .05). These cut points were associated with CVD risk 2 years later (all P < .01).

CONCLUSIONS

Muscle fitness is associated with present and future cardiovascular health in youth, and is independent of cardiorespiratory fitness. It should be monitored to identify youth at risk who could benefit from intervention programs.

Hand grip strength: Reference values for adults and elderly people of Rio Branco, Acre, Brazil

Hand grip strength (HGS) is recognized as an important health indicator, but validated reference values that can be applied to the evaluation of individuals in different populations are still lacking. This work aimed to identify correlations between HGS and anthropometric variables and to establish HGS reference values for adult and elderly populations. This is a population-based cross-sectional study considering the subsets of individuals with healthy right or left upper limbs from a sample of 1,609 adults and elderly residents in Rio Branco, Acre, Brazil. Descriptive statistics of anthropometric measures and HGS values at maximum performance based on three measurements of the two hands were obtained, and Pearson correlations between these variables were applied. Percentile distributions were estimated for right and left HGS by sex and age group. Men presented, in general, a maximum HGS 57% higher than women (43.4 kg vs. 27.6 kg), and also higher HGS levels in the different age groups. In both sexes, the highest HGS values were observed in the age group of 30 to 39 years (men, 46.9 kg; women, 29.4 kg), with a subsequent decline. HGS presented a negative correlation with age and a weak to moderate positive correlation with anthropometric variables, among men and women. The median HGS of men was reduced by about 46% between the ages of 30 and 39 years and 80 years and over (right hand, 46.4 to 23.7 kg; left hand, 42.2 to 23.5 kg) and by about 44% in women (right hand, 29.0 to 16.4 kg, left hand, 27.3 to 15.2 kg). The values identified are a reference for HGS behavior among healthy adults and seniors, although they do not discriminate individuals with specific health conditions. They can be used in rehabilitation programs and subsidize future studies aimed at exploring their potential application in the evaluation of the health condition of adults and elderly individuals.

Association between metabolic risk markers, body composition and different manifestations of strength in young adults

Introduction: For decades, low levels of muscle strength (MS) have been associated with an increased risk of mortality from all causes.Objective: To identify the correlation between values of different manifestations of MS and metabolic risk markers (MRM) in young university students.Materials and methods: The study included 50 participants (37 men, 13 women), aged between 19 and 23 years. The grip strength of both hands and the muscular strength of upper and lower limbs were evaluated, as well as height, weight, body mass index (BMI), skin folds, HDL, cholesterol and triglycerides.Results: No significant associations between MRM and the different manifestations of MS were found.Conclusion: MS and MRM are separately associated with mortality risk factors and with suffering from cardiovascular diseases

High BMI in late adolescence predicts future severe liver disease and hepatocellular carcinoma: a national, population-based cohort study in 1.2 million men

OBJECTIVE

A high body mass index (BMI) is associated with an increased risk for severe liver disease. It is unclear if this risk differs across BMI categories, and if the association is partially attributed to development of type 2 diabetes mellitus (T2DM).

DESIGN

We used register data from more than 1.2 million Swedish men enlisted for conscription between 1969 and 1996. Data regarding new events of severe liver disease and T2DM during follow-up were obtained by record-linkage of population-based registers. We used Cox regression to estimate adjusted HRs for future inpatient care and mortality in severe liver disease and incidence of hepatocellular carcinoma (HCC) across BMI categories, using BMI of 18.5-22.5 kg/m² as reference.

RESULTS

During a follow-up of more than 34 million person-years, 5281 cases of severe liver disease including 251 cases of HCC were identified. An association with severe liver disease was found for overweight (HR 1.49, 95% CI 1.35 to 1.64) and for obese men (HR 2.17, 95% CI 1.82 to 2.59). Development of T2DM further increased the risk for severe liver disease across all BMI categories, for instance, men with obesity and T2DM had a higher risk of severe liver disease (HR 3.28, 95% CI 2.27 to 4.74) than men with obesity free of T2DM (HR 1.72, 95% CI 1.72 to 2.54).

CONCLUSIONS

A high BMI in late adolescent men was associated with an increased risk of future severe liver disease, including HCC. Development of T2DM during follow-up was associated with a further increased risk of severe liver disease, independent of baseline BMI.

Association between Resting Heart Rate and Health-Related Physical Fitness in Brazilian Adolescents

The aim of this study was to identify the relationship between health-related physical fitness components (aerobic fitness, muscle strength, flexibility, and body fat) and resting heart rate (RHR) in Brazilian adolescents. The study included 695 schoolchildren (14–19 years) from public schools of the city of São José, Brazil. RHR was evaluated using an automated oscillometric sphygmomanometer. Aerobic fitness was assessed by the modified Canadian Aerobic Fitness Test; muscle strength was measured by handgrip dynamometer; flexibility was assessed by the sit-and-reach test; and body fat was assessed indirectly by sum of two skinfold thicknesses (triceps and subscapular). Sociodemographic variables, habitual physical activity, sexual maturation, and body mass index were the covariates. Cardiorespiratory fitness (β = -0.11; 95%CI: -0.14, -0.08) and handgrip strength (β = -0.10; 95%CI: -0.18, -0.01) were inversely associated with RHR in boys. For girls, cardiorespiratory fitness (β = -0.09; 95%CI: -0.12, -0.06) was inversely associated with RHR. In both sexes, body fat (β = 0.50; 95%CI: 0.25, 0.75 for boys; β = 0.17; 95%CI: 0.36, 2.72 for girls) was directly associated with RHR. The RHR is measured more easily than the physical fitness tests, so it is recommended to assess adolescent's heath in large surveillance systems.