Cut points of muscle strength associated with metabolic syndrome in men

Using Cluster Analysis to Identify Metabolic Syndrome Components and Physical Fitness in Patients with Metabolic Syndrome

Background: Metabolic syndrome (MetS) comprises a cluster of cardiovascular risk factors. Physical inactivity and reduced physical fitness are associated with one or more components of MetS. However, MetS has many components, and the unclear relationship between the components and physical fitness parameters can provide a plain and straightforward understanding of the clustering method. Aim: To identify the relationship between physical fitness parameters, physical activity levels, and components of MetS using hierarchical cluster analysis. Methods: One hundred twenty-one patients (mean age = 51.4 ± 7.1/years, F:90, M:31) who were diagnosed as having MetS according to the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) criteria were included in the study. Fasting plasma glucose (FPG), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) were analyzed. Systolic and diastolic blood pressures, (SBP and DBP), were evaluated. Body composition (waist and hip circumference, (WC and HC), waist-to-hip ratio (WHR), body mass index (BMI), percent body fat, and visceral fat), upper and lower extremity muscle strength (dynamometer), and functional exercise capacity [6-minute walk test (6MWT)] were assessed as physical fitness parameters. Physical activity levels were assessed using a pedometer and number of steps (NS) was determined. Results: Of the patients, 45.5% were diagnosed as having MetS based on four components. The dendrogram consisted of two main clusters and four subclusters. The main cluster I composed of BMI, HC, WC, visceral fat, HDL-C, percent fat, SBP, DBP, and percent quadriceps. The main cluster II comprised FPG, TG, WHR, handgrip strength, 6MWT, and NS. Conclusion: MetS components clustered with different physical fitness parameters. The clusters in the dendrogram can provide substantial implications for heterogeneous MetS components and physical fitness parameters. Future studies are needed to elucidate the effectiveness of dendrogram-derived exercise programs in MetS.

Associations of lower-limb muscle strength performance with static and dynamic balance control among older adults in Taiwan

Background

Aging is an inevitable process of life development. These physical changes can cause a decline in the functional adaptability and health status of older adult individuals.

Aims

The purpose of this study was to investigate the association of lower-limb muscle strength performance with static and dynamic balance control among older adults in Taiwan.

Methods

We conducted a cross-sectional study and reviewed data derived from the National Physical Fitness Survey in Taiwan 2015-2016. A total of 20,846 Taiwanese older adult individuals aged 65 years old or older were recruited as study participants. Demographic characteristics, anthropometric assessments, lifestyle habits, and health-related physical fitness measurements from this dataset were analyzed using the chi-square test, one-way analysis of variance, and linear regression analysis. Lower-limb muscle strength performance was classified into 4 groups based on quartile (Quartile 1 [Q1], Quartile 2 [Q2], Quartile 3 [Q3], and Quartile 4 [Q4]) values.

Results

Increased lower-limb muscle strength levels were significantly associated with static balance in men (Q2: β = 2.539, p < 0.0001; Q3: β = 4.590, p < 0.0001; Q4: β = 7.700, p < 0.0001) and women (Q2: β = 2.022, p < 0.0001; Q3: β = 4.179, p < 0.0001; Q4: β = 6.920, p < 0.0001) after adjusting for potential confounders. In addition, we observed that increased lower-limb muscle strength levels were significantly associated with dynamic balance in men (Q2: β = -1.661, p < 0.0001; Q3: β = -2.434, p < 0.0001; Q4: β = -3.091, p < 0.0001) and women (Q2: β = -1.660, p < 0.0001; Q3: β = -2.548, p < 0.0001; Q4: β = -3.196, p < 0.0001) after adjusting for potential confounders.

Conclusion

Lower-limb muscle strength was the most important factor, as it was an improved method for static and dynamic balance control in both genders.

Cut-off points for isometric handgrip and low limb explosive strength in relation to indicators of overweight/obesity in people with intellectual disabilities: analysis by age groups

BACKGROUND

The prevalence of overweight/obesity has been increasing globally and in people with Intellectual Disabilities (IDs), this problem is exacerbated even more, which added to a low physical condition that contributes to the deterioration of functionality and increases the risk of developing chronic diseases in the course of life. Therefore, the aim of this study was to establish cut-off points for levels of isometric handgrip and low limb explosive strength in children, adolescents and adults, which identify overweight/obesity in people with IDs and their respective associations.

METHODS

The sample was made up of 131 individuals with IDs, belonging to four special and community educational centres in the city of Santiago, Chile. Body mass index (BMI) and waist-to-height ratio (WHR) were used as indicators of overweight/obesity. Handgrip strength was used as a measure of isometric strength, and countermovement jump was used as a measure of low limb explosive strength. For the comparison of variables by age group, the analysis of Ancova, Kruskal-Wallis and chi-square tests were used. The total area under the receiver operating characteristic curve of isometric handgrip and low limb explosive strength was identified as an indicator of overweight/obesity according to age groups. A logistic regression model was used to quantify the effect that strength categories below the cut-off point have on the risk of overweight and obesity.

RESULTS

Significant differences were observed between the age groups for body weight, height, BMI and WHR, as well as in the levels of absolute handgrip strength and vertical jump with countermovement (P ≤ 0.05). Children showed the lowest cut-off points for absolute and relative strength. The adolescent group showed the highest cut-off points for relative strength and countermovement jump and adults showed the highest value for absolute strength as indicators of overweight/obesity. Different associations between cut-off points with BMI and WHR were found.

CONCLUSIONS

Adolescents showed the highest cut-off point for relative strength and countermovement jump, and adults showed the highest value for absolute strength, according to overweight/obesity indicators (BMI and WHR). It is suggested to adjust resistance training programmes according to age categories for the prevention of overweight/obesity in people with IDs.

Muscular strength measured across the life-course and the metabolic syndrome

BACKGROUND AND AIMS

Low muscular strength associates with the metabolic syndrome (MetS). However, how muscular strength measured at different life stages contribute to the development of MetS is unknown. This study compared the contribution of muscular strength measured in youth, young- and mid-adulthood with MetS in midlife.

METHODS AND RESULTS

Prospective longitudinal study of 267 Childhood Determinants of Adult Health Study participants who between 1985 and 2019 had measures of muscular strength (dominant grip strength) at three life stages (youth = 9-15 years, young adulthood = 26-36 years, mid-adulthood = 36-49 years) and had their MetS status assessed in mid-adulthood. Bayesian relevant life-course exposure models quantified associations between muscular strength at each life stage with MetS and estimated the maximum accumulated effect of lifelong muscular strength. The contribution of muscular strength at each life stage with MetS was equal (youth = 38%, young adulthood = 28%, mid-adulthood = 34%). A one standard deviation increase in cumulative muscular strength was associated with 46% reduced odds of MetS. Of all MetS components, muscular strength was most strongly negatively associated with high waist circumference.

CONCLUSION

A life-course approach demonstrated reduced odds of MetS in midlife was associated with cumulatively high muscular strength since youth. This supports efforts to promote physical fitness throughout life.

Association between Adjusted Handgrip Strength and Metabolic Syndrome in Arab Men

This cross-sectional study determined the association between handgrip strength (HGS) and metabolic syndrome (MetS) in Arab men. Furthermore, HGS and adjusted HGS, relative to body composition components including body mass index (BMI), body weight, and body fat percentage (%Fat), were examined in predicting MetS. Methods: In this study, 854 men participated in and completed all tests (age, 39.7 ± 15.2 years; BMI, 28.4 ± 5.2 kg/m²; %Fat, 26.6% ± 7.1%). Body composition and HGS were measured using a body impedance analyzer and a manual spring-type dynamometer, respectively. About 10 cc of venous blood was drawn once after overnight fasting and analyzed using the colorimetric method. MetS included waist circumference (WC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), blood pressure (BP), and fasting glucose were defined for the current specific population. Results: The receiver operating characteristics curve (ROC curve) showed an area under the curve (AUC) of HGS = 0.54, and 0.70 for HGS/%Fat. Linear regression analysis showed that the R² values for all three models were low in predicting MetS and its components. Lastly, the odds ratio of adjusted HGS showed that there were significant differences between all quartiles of MetS compared with the reference quartile (Q1), whereas HGS alone did not show such differences. A significant difference between the quartiles of HGS and adjusted HGS was observed in Q4 for glucose, and significant differences were also found from Q2 for hypertension in terms of the HGS and adjusted HGS. Conclusion: HGS could have protective potential for increased levels of glucose and systolic blood pressure, and using adjusted HGS rather than HGS alone is recommended for the association of MetS in Arab men.

Prevalence of Metabolic Syndrome According to Absolute and Relative Values of Muscle Strength in Middle-Aged and Elderly Women

Metabolic syndrome (MetS) increases with age, obesity, low physical activity, and decreased muscle strength. Although many studies have reported on grip strength and MetS, few studies have been conducted on leg strength. The purpose of this study was to analyze the prevalence of MetS according to absolute and relative leg strength values in middle-aged and older women. The participants were 1053 women who visited the healthcare center: middle-aged (n = 453) and older (n = 601). MetS was diagnosed using the criteria established by the third report of the National Cholesterol Education Program Adult Treatment Panel III and the World Health Organization's Asia Pacific guidelines for waist circumference. For leg strength, knee flexion and extension were performed using isokinetic equipment. Grip strength was measured using a grip dynamometer and classified into quartiles. Analysis of prevalence using logistic regression showed that MetS was present in 21.2% of middle-aged and 39.4% of older women. The lowest relative leg extension increased 2.5 times in the middle-aged and 1.5 times in older women (p < 0.05). However, leg flexion did not have a significant prevalence in either age group. The prevalence of MetS in middle-aged and older women with the lowest relative grip strength increased 1.5 and 1.2 times, respectively. Conversely, the lower the absolute leg extension strength, the lower the MetS prevalence was at 0.520 in middle-aged and 0.566 in older women (p < 0.05). In conclusion, the prevalence of MetS increased in women with low relative grip and leg strengths. Specifically, the lower the relative leg extension muscle strength, the higher the prevalence of MetS. In addition, the prevalence of MetS increased in the high-frequency alcohol consumption and non-physical activity group.

Do assessments of cardiorespiratory and muscular fitness influence subsequent reported physical activity? A randomized controlled trial

BACKGROUND

Regular physical activity and exercise provide many health benefits. These health benefits are mediated in large part through cardiorespiratory fitness and muscular strength. As most individuals have not had an assessment of their personal cardiorespiratory fitness or muscular strength we investigated if measurements of cardiorespiratory fitness and muscular strength would influence an individual's subsequent self-reported exercise and physical activity.

METHODS

Volunteer subjects at a State Fair were randomized in 1:1 parallel fashion to control and intervention groups. The baseline Exercise Vital Sign (EVS) and type of physical activity were obtained from all subjects. The intervention group received estimated maximum oxygen uptake (VO2max) using a step test and muscular strength using a hand grip dynamometer along with age-specific norms for both measurements. All subjects were provided exercise recommendations. Follow up surveys were conducted at 3, 6 and 12 months regarding their EVS and physical activity.

RESULTS

One thousand three hundred fifteen individuals (656 intervention, 659 control) were randomized with 1 year follow up data obtained from 823 subjects (62.5%). Baseline mean EVS was 213 min/week. No change in EVS was found in either group at follow-up (p = 0.99). Subjects who were less active at baseline (EVS < 150) did show an increase in EVS (86 to 146) at 6 months (p < 0.05). At 3 months the intervention group increased resistance training (29.1 to 42.8%) compared to controls (26.3 to 31.4%) (p < 0.05). Lifestyle physical activity increased in the intervention group at 3 months (27.7 to 29.1%) and 6 months (25%) whereas it declined in the control group at 3 months (24.4 to 20.1%) and 6 months (18.7%) (p < 0.05).

CONCLUSION

Providing VO2max estimates and grip strength did not produce an increase in overall physical activity. The EVS and exercise recommendations did however produce an increase in physical activity in less active individuals. In a very active population the VO2max estimate and measured grip strength did increase lifestyle activity and resistance training. Wider adoption of these measures could be effective in promoting physical activity and resistance training.

TRIAL REGISTRATION

clinicaltrials.gov NCT03518931 Registered 05/08/2018 -retrospectively registered.

Muscle strength cut-points for metabolic syndrome detection among adults and the elderly from Brazil

We aimed to determine cut-points for muscle strength based on metabolic syndrome diagnosis. This cross-sectional analysis comprised data from 2 cohorts in Brazil (EpiFloripa Adult, n = 626, 44.0 ± 11.1 years; EpiFloripa Aging, n = 365, 71.6 ± 6.1 years). Metabolic syndrome was assessed by relative handgrip strength (kgf/kg). Metabolic syndrome was defined as including ≥3 of the 5 metabolic abnormalities according to the Joint Interim Statement. Optimal cut-points from Receiver Operating Characteristic (ROC) curves were determined. Adjusted logistic regression was used to test the association between metabolic syndrome and the cut-points created. The cut-point identified for muscle strength was 1.07 kgf/kg (Youden index = 0.310; area under the curve (AUC)) = 0.693, 95% CI 0.614-0.764) for men and 0.73 kgf/kg (Youden index = 0.481; AUC = 0.768, 95% confidence interval (CI) = 0.709-0.821) for women (age group 25 to < 50 years). The best cut-points for men and women aged 50+ years were 0.99 kgf/kg (Youden index = 0.312; AUC = 0.651; 95% CI = 0.583-0.714) and 0.58 kgf/kg (Youden index = 0.378; AUC = 0.743; 95% CI = 0.696-0.786), respectively. Cut-points derived from ROC analysis have good discriminatory power for metabolic syndrome among adults aged 25 to <50 years but not for adults aged 50+ years. Novelty: First-line management recommendation for metabolic syndrome is lifestyle modification, including improvement of muscle strength. Cut-points for muscle strength levels according to sex and age range based on metabolic syndrome were created. Cut-points for muscle strength can assist in the identification of adults at risk for cardiometabolic disease.

Cardiorespiratory fitness is strongly linked to metabolic syndrome among physical fitness components: a retrospective cross-sectional study

BACKGROUND

Maintaining a good level of physical fitness from engaging in regular exercise is important for the treatment and prevention of metabolic syndrome (MetS). However, which components constitutive of physical fitness confer the greatest influence remains controversial. This retrospective cross-sectional study aimed to investigate the association between MetS and physical fitness components including cardiorespiratory fitness, muscle strength, flexibility, and agility and to identify which physical fitness components have the largest influence on MetS.

METHODS

A total of 168 Japanese adult males aged 25-64 years were allocated into non-MetS, pre-MetS, and MetS groups according to the criteria recommended by the Japanese Society of Internal Medicine. Anthropometric measurement of body composition by whole-body dual-energy X-ray absorptiometry and measures related to MetS, including waist circumference, triglyceride level, high-density lipoprotein cholesterol level, blood pressure, glucose level, and physical fitness components, were assessed. For evaluation of cardiorespiratory fitness, muscle strength, flexibility, agility, and balance, maximal oxygen consumption (VO_2peak) and oxygen uptake at anaerobic threshold (VO_2AnT), handgrip strength and vertical jumping, trunk extension and flexion, stepping side to side, and single-leg balance task with the eyes closed were assessed, respectively.

RESULTS

A progressive tendency of increasing body weight, body mass index, whole-body lean and fat mass, percentage of whole-body fat mass, trunk lean and fat mass, percentage of trunk fat mass, arm fat mass, waist circumference, triglyceride level, systolic and diastolic blood pressure, and blood glucose level from the non-MetS group to the MetS group was significant (P < 0.05). Conversely, the cardiorespiratory endurance parameters VO_2peak and VO_2AnT and the high-density lipoprotein cholesterol level showed a progressively decreasing tendency across the groups (P < 0.01). In addition, a VO_2peak below 29.84 ml·kg·min^-1 (P = 0.028) and VO2_AnT below 15.89 ml·kg·min^-1 (P = 0.011) were significant risk components for pre-MetS and MetS. However, there was no significant tendency with respect to muscle strength, agility, and flexibility.

CONCLUSION

Cardiorespiratory fitness is strongly linked to metabolic syndrome among physical fitness components.

Normative Values of Knee Extensor Isokinetic Strength for Older Women and Implications for Physical Function

BACKGROUND AND PURPOSE

Lower-limb strength is required for everyday activities and thus its evaluation has been especially emphasized in older adults. Isokinetic testing is a criterion standard method to assess muscle strength; however, lack of reference values limits its usefulness in geriatric evaluation and rehabilitation. The aim of this study was to develop reference values of knee extensor isokinetic strength for older women. As a secondary aim, functional tests were performed for clinical significance validation.

METHODS

A total of 453 older women aged 60 to 84 years participated in this study. Knee extensor isokinetic strength was measured using the Biodex System dynamometer at 60° per second. The Timed Up and Go test and the 5 times Sit-to-Stand test were used for functional performance evaluation. Participants were categorized into age groups of 5 years range. The 20th, 40th, 60th, and 80th percentiles were used for stratification purposes.

RESULTS AND DISCUSSION

As expected, mean strength values significantly decreased with advancing age groups. Isokinetic percentile groups are presented according to age. Individuals in the lower percentile strata showed significantly reduced performance in both the Timed Up and Go and 5 times Sit-to-Stand tests (P < .05).

CONCLUSION

This study provides normative values of isokinetic knee extensor strength in older women. The association between lower isokinetic knee extensor strength strata and reduced functional capacity supports the potential application of these reference values in clinical and research settings. Future studies should ascertain these findings in different female populations.

Grip Strength Cut Points for Diabetes Risk Among Apparently Healthy U.S. Adults

INTRODUCTION

Early detection screening tools are needed to aid in preventing vascular complications associated with type 2 diabetes. As low muscular strength is linked to increased diabetes risk, the purpose of this study is to establish muscular strength cut points for determining diabetes risk using a large, nationally representative U.S.

METHODS

Using the 2011-2012 and 2013-2014 National Health and Nutrition Examination Survey data, 5,108 participants aged 20-80 years (68.6% aged 20-50 years; young male participants, n=1,813, mean age=33.43 years; young female participants, n=1,692, mean age=33.39 years; older male participants, n=813, mean age=59.92 years; older female participants, n=790, mean age=60.45 years) and free of common diabetes comorbidities were included. Muscular strength was assessed using a handgrip dynamometer and normalized by adjusting for body weight. A logistic regression for survey data controlling for covariates was used to determine normalized grip strength cut points. Diabetes risk was determined using American Diabetes Association diagnostic criteria. Analyses were conducted in the summer of 2019.

RESULTS

Normalized grip strength significantly predicted diabetes (p=0.0332), and the cut points for detecting diabetes risk included 0.78 (young male participants), 0.57 (young female participants), 0.68 (older male participants), and 0.49 (older female participants). The risk percentages for diabetes and estimated rates reported for all subgroups were comparable, and the risk percentages included 6.84 (95% CI=5.32, 8.36; younger male participants), 7.49 (95% CI=5.87, 9.10; younger female participants), 5.76 (95% CI=2.34, 9.19, older male participants), and 4.27 (95% CI=2.44, 6.10; older female participants).

CONCLUSIONS

Normalized grip strength using the cut points proposed in this paper may be a useful screening tool for diabetes risk in apparently healthy, normotensive adults.

Association of handgrip strength with the prevalence of metabolic syndrome in US adults: the national health and nutrition examination survey

OBJECTIVE

Aimed to find the cut-off point of handgrip strength and it's association with MetS.

RESULTS

The relative handgrip strength was negatively associated with the prevalence of MetS. Of note, the odds ratios (ORs) with 95% confidence intervals (CIs) across tertiles of relative handgrip strength were 1 (reference), 0.45 (0.33, 0.62), and 0.13 (0.08, 0.20) in male participants after adjusting for demographic factors, calorie intake, and physical activity. Similar results were observed in female participants. The cutoff values of relative handgrip strength for male and female participants were 0.52 and 0.40, respectively.

CONCLUSIONS

Findings of this study suggest that a strong relationship exists between handgrip strength and prevalence of MetS in US adults, regardless of sex.

METHODS

A total of 5 056 participants in the National Health and Nutrition Examination Survey were analysed in this study. Handgrip strength was measured by using a handgrip dynamometer. MetS was defined in accordance with the criteria of the scientific statement of the American Heart Association in 2009. Multivariable binary logistic regression was used to explore the association between handgrip strength and MetS.

Muscle strength cut-offs for the detection of metabolic syndrome in a nonrepresentative sample of collegiate students from Colombia

BACKGROUND

Evidence shows an association between grip strength and health; however, grip strength cut-offs for the detection of metabolic syndrome (MetS) in Latin American populations are scarce. The purpose of this study was to determine cut-offs of normalized grip strength (NGS) for the detection of MetS in a large nonrepresentative sample of a collegiate student population from Colombia.

METHODS

A total of 1795 volunteers (61.4% female; age = 20.68 ± 3.10 years, mean ± SD), ranging between 18 and 30 years of age participated in the study. Strength was estimated using a handheld dynamometer and normalized to body mass (handgrip strength (kg)/body mass (kg)). Anthropometrics, serum lipids indices, blood pressure, and fasting plasma glucose were measured. Body composition was measured by bioelectrical impedance analysis. MetS was defined as including ≥3 of the 5 metabolic abnormalities according to the International Diabetes Federation definition. A metabolic risk score was computed from the following components: waist circumference, triglycerides, high-density lipoprotein cholesterol, glucose, and systolic and diastolic blood pressure.

RESULTS

Receiver operating curve analysis showed significant discriminatory accuracy of NGS in identifying the thresholds and risk categories. Lower strength was associated with increased prevalence of MetS. In males, weak, intermediate, and strong NGS values at these points were <0.466, 0.466-0.615, >0.615, respectively. In females, these cut-off points were <0.332, 0.332-0.437, >0.437, respectively.

CONCLUSION

Our sex-specific cut-offs of NGS could be incorporated into a clinical setting for identifying college students at cardiometabolic disease risk.

Evidence-Based Optimal Cutoff Values with the Validation of Criterion-Referenced Standards for Sarcopenic Elderly Fitness Improvement

This study provides a newly updated perspective of information on severely screened 21 previous studies of the various measurement methods for improving physical fitness and providing determined cutoff values from our reserved elderly human database. We aimed to provide scientific evidence-based information regarding physical fitness standards for developing useful prognostics, promoting and maintaining health programs for sarcopenic elderly. 21 previous studies emphasizing criterion referenced standards and receiver operator characteristic (ROC) curve analyses for improving physical fitness were screened. For predicting the prevalence of sarcopenia, the t-test, logistic regression, linear regression, ROC curve analyses, and voluntary categorizations such as the twentieth or sixtieth percentile classification were used. Based on these scientific evidences, we determined cutoff values from our reserved DB and realized that 75 years for men and 70 years for women are the transitional period during which there are large declines in muscle and fat mass (p<0.01), which reflects physical function tests (p<0.01) in both genders. Using the six factors with ideal cutoff thresholds, an individual exercise program can be designed for alleviating symptoms of frailty caused by sarcopenia for the elderly.

Evidence-Based Optimal Cutoff Values with the Validation of Criterion-Referenced Standards for Sarcopenic Elderly Fitness Improvement

This study provides a newly updated perspective of information on severely screened 21 previous studies of the various measurement methods for improving physical fitness and providing determined cutoff values from our reserved elderly human database. We aimed to provide scientific evidence-based information regarding physical fitness standards for developing useful prognostics, promoting and maintaining health programs for sarcopenic elderly. 21 previous studies emphasizing criterion referenced standards and receiver operator characteristic (ROC) curve analyses for improving physical fitness were screened. For predicting the prevalence of sarcopenia, the t-test, logistic regression, linear regression, ROC curve analyses, and voluntary categorizations such as the twentieth or sixtieth percentile classification were used. Based on these scientific evidences, we determined cutoff values from our reserved DB and realized that 75 years for men and 70 years for women are the transitional period during which there are large declines in muscle and fat mass (p < 0.01), which reflects physical function tests (p < 0.01) in both genders. Using the six factors with ideal cutoff thresholds, an individual exercise program can be designed for alleviating symptoms of frailty caused by sarcopenia for the elderly.

Do Nationally Representative Cutpoints for Clinical Muscle Weakness Predict Mortality? Results From 9 Years of Follow-up in the Health and Retirement Study

BACKGROUND

Muscle weakness, as measured by handgrip strength, is associated with cardiovascular and all-cause mortality; however, there are wide inconsistencies in the magnitude of these effects due to divergent definitions used to define muscle weakness across studies. Therefore, the objective of this study was to examine the relationship between previously defined sex- and race-specific cutpoints of clinical muscle weakness and early mortality.

METHODS

Data come from the 2006-2014 Health and Retirement Study. Time-varying clinical muscle weakness, as defined by handgrip strength cutpoints, was the primary exposure. Time to death, ascertained from the National Death Index, was the outcome of interest. The association between time-varying clinical muscle weakness and early mortality across a 9-year observation period was determined using Kaplan-Meier methods and extended Cox regression.

RESULTS

Out of the 8,326 individuals in the study, 1,799 deaths (21%) occurred during the observation period. Median follow-up time was 8.3 years (SD ±1.9 years). Weak individuals had a steeper decline in their survival trajectory, compared to non-weak individuals (Log-Rank test, p < .001). After adjusting for sociodemographic factors and time-varying smoking history, weak individuals were over 50% more likely to die earlier than non-weak individuals (hazard ratio [HR] = 1.52, 95% confidence interval [CI] = 1.15, 1.47).

CONCLUSIONS

This is the first study to use muscle weakness cutpoints derived in a nationally representative sample to identify those individuals who may be at greatest risk for premature mortality. Results underscore the importance of muscle weakness, as defined by handgrip strength, as a key risk factor for premature mortality in older Americans.

Diabetic Peripheral Neuropathy Is Associated With Higher Systolic Blood Pressure in Adults With Type 2 Diabetes With and Without Hypertension in the Chinese Han Population

OBJECTIVES

Our aim in this study was to investigate the association between diabetic peripheral neuropathy (DPN) and above-normal blood pressure in nonhypertensive adult patients with type 2 diabetes mellitus (T2DM). We also compared achievement of clinical targets for DPN and non-DPN with T2DM.

METHODS

A retrospective survey was administered to 3,810 patients with T2DM. Cases were grouped according to the Toronto Clinical Scoring System as follows: non-DPN, mild DPN, moderate DPN and severe DPN. A total of 1,835 patients (hypertensive, 1,247; nonhypertensive, 588) also underwent nerve conduction velocity testing, and then was divided into quartile groups.

RESULTS

Irrespective of hypertension, systolic blood pressure (SBP) and glycated hemoglobin levels in the DPN group were higher than those in the non-DPN group (p<0.001). In hypertensive patients, blood pressure goal achievement was lower in the DPN group compared with the non-DPN group (31.1% vs 40.5%, p<0.05). Compared with the nerve conduction velocity Q1 (<P25%) group, optimal SBP of the Q2 (P25% to P50%), Q3 (P50% to P75%) and Q4 (>P75%) groups decreased by 62.2%, 68.2% and 78.0%, respectively. In the nonhypertensive patients, detection of optimal SBP was lower in the DPN group than in the non-DPN group (p<0.05). After adjusting for age, sex and diabetes duration (model 2), a 3-point higher DPN score on the Toronto Clinical Scoring System was associated with an SBP level of 4.2 mmHg higher (95% confidence interval, 0.01 to 0.17; p<0.01) in nonhypertensive patients with diabetes.

CONCLUSIONS

DPN is associated with difficulty in hypertension management in T2DM. It is also associated with elevated systolic blood hypertension, even in nonhypertensive patients with diabetes. Elevated SBP in nonhypertensive T2DM may be also worthy of further attention.

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

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

Sarcopenic Obesity: Epidemiologic Evidence, Pathophysiology, and Therapeutic Perspectives

PURPOSE OF REVIEW

This review provides a comprehensive update on the definition, assessment, epidemiology, pathophysiology, clinical implications, and therapeutic approach of sarcopenic obesity (SO) and highlights the challenges, limitations, and knowledge gaps in SO research.

RECENT FINDINGS

The confluence of a rapidly aging population with rising obesity rates has led to the phenotype of SO, defined as the concurrent presence of sarcopenia and obesity. Despite efforts, a standardized definition of SO is still lacking. Its prevalence varies widely between studies, depending on population characteristics and different definitions. The major pathogenetic mechanisms include age-related changes in body composition and hormonal milieu, positive energy balance, pro-inflammatory pathways, and insulin resistance. Lifestyle interventions, including caloric restriction and physical activity, are the cornerstones of SO treatment. SO is a multifaceted syndrome with serious clinical implications. The development and implementation of effective prevention and treatment strategies is a top priority based on its dramatically increasing health impact.

Glomerular hyperfiltration may be a novel risk factor of restrictive spirometry pattern: Analysis of the Korea National Health and Nutrition Examination Survey (KNHANES) 2009-2015

BACKGROUND AND OBJECTIVES

There have been limited studies regarding the association between glomerular hyperfiltration (GHF) and restrictive spirometry pattern (RSP) in Korean adults.

METHODS

We used data of 23,189 adults from the Korea National Health and Nutritional Examination Survey 2009-2015 with a complete data set including spirometry, serum creatinine, and anthropometric measurements. Spirometry data included the forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). We defined GHF as the >90th percentile of age & sex adjusted estimated glomerular filtration rate (eGFR), and RSP was defined as an FVC <80%-predicted value and an FEV1/FVC ratio ≥0.7.

RESULTS

Participants with RSP showed higher blood pressure, fasting glucose, and triglyceride, reduced high density lipoprotein cholesterol, and central obesity, which resulted in a higher prevalence of metabolic syndrome (MetS) compared to those without RSP. Multivariate logistic regression revealed that the odds for RSP were significantly increased with an increased number of MetS components. In addition, increased eGFR was associated with decreased FVC, showing an inverted J-shaped relationship in a multivariate generalized additive model analysis. In the multivariate logistic regression analysis, the adjusted odds ratio and 95% confidence interval of GHF for RSP was 1.184 (1.026-1.368, P = 0.021), which was evident in groups without metabolic disorders.

CONCLUSIONS

We concluded that GHF was associated with increased odds for RSP, particularly in groups without metabolic disorders. Further prospective studies are needed to confirm our study results.

Association of cognitive impairment and grip strength trajectories with mortality among middle-aged and elderly adults

ABSTRACTBackground:This study investigates whether maintaining high levels of cognitive impairment and weak grip strength will predict a higher risk for mortality.

METHODS

Data from the Korean Longitudinal Study of Aging (KLoSA) from 2006 to 2014 was assessed using longitudinal data analysis and included 5,812 research subjects. Our modeling approach jointly estimated multi-period trajectories of grip strength and cognitive impairment, and the primary analysis was based on Cox proportional hazards models.

RESULTS

A four-class linear solution fit the data best in both cognitive impairment and grip strength based on the model fitness, respectively. The hazard ratio (HR) of mortality in group 1 (consistently low) of cognitive impairment and of grip strength were 2.114 times higher (p-value 0.001) and 3.405 times higher (p-value &lt;.0001) compared with group 3 (consistently high) and group 4 (consistently high), respectively.

CONCLUSION

This study provides insightful scientific evidence into the specificity of longitudinal changes in grip strength and cognitive impairment on mortality. Our findings suggest that declined cognitive ability and weak grip strength are predictors of mortality in older Korean people.

Clinical relevance of different handgrip strength indexes and cardiovascular disease risk factors: A cross-sectional study in suburb-dwelling elderly Chinese

BACKGROUND

Reduced muscle strength, as measured by handgrip strength (HS), has been associated with an increased risk of cardiovascular disease (CVD). The aim of this study was to examine the association between different HS indexes and CVD risk factors in elderly Chinese individuals. We also determine optimal cutoffs of HS indexes for predicting CVD risk factors.

METHODS

Data were obtained from 603 men and 789 women aged ≥60 years (average age 66.8 ± 6.4 y). These study participants were recruited in the suburb area of Tianjin, China. An individual was considered a patient when they exhibited any one of three CVD risk factors: diabetes mellitus, hypertension and dyslipidemia. All participants were interviewed face-to-face. In addition, serum samples were collected from all participants, and all participants underwent measures of anthropometry and HS.

RESULTS

The optimal cutoffs were 0.376 of HS/weight in men and 0.726 of HS/body fat mass in women for predicting diabetes mellitus. The adjusted odds ratios (ORs) of at least one CVD risk factor for those with low muscle strength identified by HS/body fat mass were 2.14 (95% confidence interval [CI]: 1.53, 3.44; p < 0.001) in men and 2.32 (95% CI: 1.60, 3.29; p < 0.001) in women.

CONCLUSION

HS/body fat mass appear to be the index best associated with CVD risk factors except diabetes mellitus in men. The optimal cutoffs of HS indexes have the potential to identify elderly adults at risk of CVD.

Association between hand-grip strength and erectile dysfunction in older men

OBJECTIVES

To evaluate the association between handgrip strength and erectile dysfunction (ED) in community-dwelling older men.

METHODS

This cross-sectional study included 1771 participants of the Dong-gu Study. Handgrip strength was measured with a handheld dynamometer. ED was assessed with the Korean version of the International Index of Erectile Function (IIEF). ED was categorized as none to mild (IIEF-EF scores of 13-30) and moderate to severe (IIEF-EF scores of 0-12). Multivariable logistic regression was conducted with adjustment for potential confounders.

RESULTS

The proportion of men with moderate to severe ED was 48.8%. The age-adjusted ED score increased with increasing quartile of handgrip strength (11.0, 12.4, 13.4, and 14.0 in the lowest, second, third, and highest quartiles, respectively). After adjustment for potential confounders, greater handgrip strength was associated with a lower risk of ED (odds ratio (OR): 0.82 per 5 kg; 95% confidence interval (CI): 0.74-0.90). In addition, a high level of moderate to vigorous physical activity was associated with a lower risk of ED (OR: 0.75; 95% CI: 0.61-0.93).

CONCLUSION

In this study, aging men with greater handgrip strength had a lower risk of ED. This result suggests that reduced physical functioning may contribute to ED.

Physical Fitness and Metabolic Syndrome in Brazilian Adolescents: Validity of Diagnostic Health Criteria

We tested health criteria cutoff points from physical fitness variables proposed by the Fitnessgram program for detecting metabolic syndrome ( MetS) in a representative sample of 1,035 Brazilian adolescents (565 girls and 470 boys) aged 12-20 years. We studied five fitness tests: (a) back-saver sit and reach, (b) trunk lift, (c) curl-up, (d) push-up, and (e) progressive aerobic cardiovascular endurance run ( PACER), and we defined MetS through the criteria of the International Diabetes Federation. We described the predictive performance of each fitness test in terms of sensitivity, specificity, and area under the curve ( AUC) estimates of the receiver operating characteristic method. The AUCs for four tests ( back-saver sit and reach, trunk lift, curl-up, and push-up) revealed low accuracy for identifying MetS in both sexes (0.50 ≥ AUC ≤ 0.60), but AUCs for the PACER test demonstrated good accuracy values between 0.72 (0.68-0.76) and 0.83 (0.78-0.89). Thus, cutoff points proposed in the Fitnessgram program for the PACER test offer an effective means of screening adolescents at higher cardiometabolic risk, which, for the age-group used in this study, should be from 40.3-44.3 ml/kg/min for boys and 38.6-40.1 ml/kg/min for girls.

Exploring the Link between Serum Phosphate Levels and Low Muscle Strength, Dynapenia, and Sarcopenia

Emerging evidences addressed an association between phosphate and muscle function. Because little attention was focused on this issue, the objective of our study was to explore the relationship of phosphate with muscle strength, dynapenia, and sarcopenia. From the National Health and Nutrition Examination Survey, a total of 7421 participants aged 20 years or older were included in our study with comprehensive examinations included anthropometric parameters, strength of the quadriceps muscle, and appendicular lean masses. Within the normal range of serum phosphate, we used quartile-based analyses to determine the potential relationships of serum phosphate with dynapenia, and sarcopenia through multivariate regression models. After adjusting for the pertinent variables, an inverse association between the serum phosphate quartiles and muscle strength was observed and the linear association was stronger than other anthropometric parameters. Notably, the significant association between phosphate and muscle strength was existed in >65 years old age group, not in 20-65 years old. The higher quartiles of phosphate had higher likelihood for predicting the presence of dynapenia rather than sarcopenia in entire population. Our study highlighted that higher quartiles of phosphate had significant association with lower muscle strength and higher risks for predicting the presence of dynapenia.

Influence of segmental body composition and adiposity hormones on resting metabolic rate and substrate utilization in overweight and obese adults

PURPOSE

Low resting metabolic rate (RMR) and high carbohydrate reliance at rest are associated with weight gain, but are highly variable in obese individuals. This study determined the relationship of total and segmental body composition and adiposity hormones with RMR and respiratory exchange ratio (RER) in overweight and obese adults.

METHODS

In 49 men (n = 23) and premenopausal women (n = 26) [mean ± SD; age = 35.0 ± 8.9 years; body mass index (BMI) = 33.6 ± 5.2 kg·m^-2; percent body fat (%fat) = 40.0 ± 8.0%], RMR and RER were evaluated using indirect calorimetry. Total and segmental body composition [fat mass (FM), percent fat (%fat), lean mass (LM), visceral adipose tissue (VAT)] were estimated using dual-energy X-ray absorptiometry. Fasted blood and saliva samples were analyzed for insulin, leptin, estradiol, and cortisol.

RESULTS

In men (M) and women (W), RMR significantly correlated (p < 0.05) with FM (M: R = 0.535; W: R = 0.784) and LM (M: R = 0.645; W: R = 0.867). Of the segmental measures, trunk LM (M: R = 0.593; W: R = 0.879; p < 0.05) and leg LM (M: R = 0.664; W: R = 0.821; p < 0.05) had the strongest correlations with RMR. In men, but not women, RER significantly correlated with FM (R = 0.449; p = 0.032), trunk FM (R = 0.501; p = 0.015), and VAT (R = 0.456; p = 0.029). In men, RMR positively correlated with cortisol (R = 0.430, p = 0.040) and estradiol (R = 0.649, p = 0.001) and RER positively correlated with insulin (R = 0.525, p = 0.010). In women, RMR positively correlated with insulin (R = 0.570, p = 0.006), but RER was not significantly correlated with hormones (p > 0.05).

CONCLUSIONS

Segmental evaluation of body composition, specifically in the lower extremities and abdomen, may be an effective and efficient way to evaluate metabolic status. Sex-specific evaluations are also imperative.

Muscle Weakness Thresholds for Prediction of Diabetes in Adults

BACKGROUND

Despite the known links between weakness and early mortality, what remains to be fully understood is the extent to which strength preservation is associated with protection from cardiometabolic diseases, such as diabetes.

PURPOSE

The purposes of this study were to determine the association between muscle strength and diabetes among adults, and to identify age- and sex-specific thresholds of low strength for detection of risk.

METHODS

A population-representative sample of 4066 individuals, aged 20-85 years, was included from the combined 2011-2012 National Health and Nutrition Examination Survey (NHANES) data sets. Strength was assessed using a handheld dynamometer, and the single highest reading from either hand was normalized to body mass. A logistic regression model was used to assess the association between normalized grip strength and risk of diabetes, as determined by haemoglobin A1c levels ≥6.5 % (≥48 mmol/mol), while controlling for sociodemographic characteristics, anthropometric measures and television viewing time.

RESULTS

For every 0.05 decrement in normalized strength, there were 1.26 times increased adjusted odds for diabetes in men and women. Women were at lower odds of having diabetes (odds ratio 0.49; 95 % confidence interval 0.29-0.82). Age, waist circumference and lower income were also associated with diabetes. The optimal sex- and age-specific weakness thresholds to detect diabetes were 0.56, 0.50 and 0.45 for men at ages of 20-39, 40-59 and 60-80 years, respectively, and 0.42, 0.38 and 0.33 for women at ages of 20-39, 40-59 and 60-80 years, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

We present thresholds of strength that can be incorporated into a clinical setting for identifying adults who are at risk of developing diabetes and might benefit from lifestyle interventions to reduce risk.

Influence of Relative Strength on Functional Independence of Patients With Spinal Cord Injury

OBJECTIVE

To investigate the influence of strength values and fat mass on functional independence of men with different spinal cord injury (SCI) levels.

DESIGN

Cross-sectional study.

SETTING

Hospital network.

PARTICIPANTS

Men with SCI (N=45).

INTERVENTIONS

Subjects were assessed in functional independence scales, a 1 repetition maximum (1RM) test, and body composition to detect absolute and relative strength: 1RM divided by body mass (BM) and lean body mass (LBM), respectively.

MAIN OUTCOME MEASURES

Stepwise multiple regression analysis was used to verify the influence of predictors on functional independence (FIM and Spinal Cord Independence Measure [SCIM] scale and subscales). Receiver operating characteristic curves were created to identify cutoff points of strength for functional independence.

RESULTS

The best models for FIM total, FIM mobility, and SCIM total used 1RM as the best predictor (adjusted R²=.75, .67, and .65, respectively; P<.05). Relative strength (1RM/LBM) was the best predictor for SCIM mobility (adjusted R²=.62, P<.05). A FIM score of 69 has a 1RM cutoff point of 50.1kg, and a FIM score of 76 has cutoff points of .73 for 1RM/BM and .91 for 1RM/LBM. A SCIM score of 68 has cutoff points for 1RM, 1RM/BM, and 1RM/LBM of 50.1kg, .77, and .92, respectively.

CONCLUSIONS

Cutoff points of relative strength should be used as determinant variables for independence, health, or sports performance. This study may contribute to more adequate guidance of physical activity during a rehabilitation program and after discharge.

Physical activity and sarcopenic obesity: definition, assessment, prevalence and mechanism

Sarcopenic obesity is the coexistance of sarcopenia and obesity. Modern sarcopenia definition includes low muscle mass, weak muscle strength (handgrip strength) and poor physical function (slow walking), although the clinical definition of each varies worldwide. The cut-points for low muscle mass for men and women using appendicular lean mass divided by height (kg/m2) are ≤7.0 and ≤5.4 in Asians, and ≤7.23 and ≤5.67 in Caucasians, respectively. The cut-points for weak handgrip strength (kg) for men and women are <26 and <18 in Asians, and <30 and <20 in Caucasians, respectively. The cut-point for slow walking is ≤0.8 m/s in men and women. Current data suggest the potential benefits of physical activity and fitness on sarcopenic obesity in older adults.

Muscle Weakness Is Associated With Diabetes in Older Mexicans: The Mexican Health and Aging Study

BACKGROUND

The risk of cardiovascular problems due to diabetes mellitus is highest among older Mexicans, and yet what remains to be determined is the association between muscle weakness and diabetes in this population. Therefore, the purpose of this study was to determine the association between muscle strength and diabetes among Mexican adults greater than 50 years of age.

DESIGN

Cross-sectional.

SETTING

National sample of households in both urban and rural areas.

PARTICIPANTS

A subsample of 1841 individuals aged 50 years and older was included from the 2012 Mexican Health and Aging Study.

MEASUREMENTS

Strength was assessed using a hand-held dynamometer, and the single largest reading from either hand was normalized to body mass (normalized grip strength [NGS]). Conditional inference tree analyses were used to identify sex-specific NGS weakness thresholds. Linear regression was used to examine the association between NGS and HbA1c, and logistic regression was used to assess the association between weakness and risk of diabetes (HbA1c ≥ 6.5% [≥48 mmol/mol]), after controlling for age, sex, and waist circumference.

RESULTS

NGS was inversely associated with HbA1c (β = -1.56; P < .001). Optimal sex-specific NGS weakness thresholds to detect diabetes were ≤0.46 and ≤0.30 for men and women, respectively. Weakness was associated with significantly increased odds of diabetes (odds ratio, 1.69; 95% confidence interval, 1.37-2.10), even after adjusting for age, sex, and waist circumference.

CONCLUSIONS

NGS was robustly associated with diabetes and other cardiometabolic risk factors in older Mexicans. This simple screen may serve as a valuable tool to identify adults that are at risk for negative health consequences or early mortality and who might benefit from lifestyle interventions to reduce risk.

Psychosocial mediators of a theory-based resistance training maintenance intervention for prediabetic adults

OBJECTIVE

Examine psychosocial mediators of the effects of high vs. low-dose resistance training (RT) maintenance interventions among older (ages 50-69), overweight and pre-diabetic adults.

DESIGN

Participants (N = 123) completed a three-month supervised RT initiation phase and were subsequently randomised (time 1) to high or low-dose six-month unsupervised RT maintenance interventions (time 2), followed by a six-month no-contact phase (time 3).

MAIN OUTCOME MEASURES

Online measures of putative mediators and RT behaviour.

RESULTS

RT intervention condition (high vs. low dose) had significant effects on change from time 1 to time 2 in behavioural expectation, self-regulation and perceived satisfaction (f(2) = .04-.08), but not outcome expectancies, RT strategies or behavioural intentions (f(2) ≤ .02). Change in each of the putative mediators, except for outcome expectancies (f(2) ≤ .02), had significant effects on RT behaviour at times 2 (f(2) = .12-.27) and 3 (f(2) = .23-.40). In a multiple mediation model, behavioural expectation (f(2) = .11) and self-regulation (f(2) = .06) mediated the effects of RT intervention condition on time 2 RT behaviour, whereas perceived satisfaction did not (f(2) = .01). Self-regulation was a significant mediator of intervention effects on time 3 RT behaviour (f(2) = .11), but behavioural expectation and perceived satisfaction were not (f(2) = .04).

CONCLUSIONS

Findings suggest that behavioural expectation and self-regulation are appropriate targets for RT maintenance interventions among at-risk older adults.

Low Muscle Strength Thresholds for the Detection of Cardiometabolic Risk in Adolescents

INTRODUCTION

There is an association between strength and health among adolescents, yet, what remains to be determined is sex-specific cut points for low strength in the detection of risk in this population. The purpose of this study was to determine thresholds of low grip strength in a large cohort (N=1,326) of adolescents.

METHODS

All data were collected between 2005 and 2008, and analyzed in 2014-2015. A cardiometabolic risk score (MetScore) was computed from the following components: percent body fat, fasting glucose, blood pressure, plasma triglyceride levels, and high-density lipoprotein cholesterol. A high-risk cardiometabolic phenotype was characterized as ≥75th percentile of the MetScore. Conditional inference tree analyses were used to identify sex-specific, low normalized strength (grip strength/body mass) thresholds and risk categories.

RESULTS

Lower strength was independently associated with increased odds of the high-risk cardiometabolic phenotype, such that for every 5% decrement of normalized strength, there were 1.48 and 1.45 increased odds (p<0.001) for boys and girls, even after adjusting for cardiorespiratory fitness and physical activity. Conditional tree analysis revealed a high-risk threshold for boys (≤0.33) and girls (≤0.28), as well as an intermediate threshold (boys, >0.33 and ≤0.45; girls, >0.28 and ≤0.36).

CONCLUSIONS

These sex-specific thresholds of low strength can be incorporated into a clinical setting for identifying adolescents that would benefit from lifestyle interventions to improve muscular fitness and reduce cardiometabolic risk.

Declines in Strength and Mortality Risk Among Older Mexican Americans: Joint Modeling of Survival and Longitudinal Data

BACKGROUND

Grip strength is a noninvasive method of risk stratification; however, the association between changes in strength and mortality is unknown. The purposes of this study were to examine the association between grip strength and mortality among older Mexican Americans and to determine the ability of changes in strength to predict mortality.

METHODS

Longitudinal data were included from 3,050 participants in the Hispanic Established Population for the Epidemiological Study of the Elderly. Strength was assessed using a hand-held dynamometer and normalized to body mass. Conditional inference tree analyses were used to identify sex- and age-specific weakness thresholds, and the Kaplan-Meier estimator was used to determine survival estimates across various strata. We also evaluated survival with traditional Cox proportional hazard regression for baseline strength, as well as with joint modeling of survival and longitudinal strength change trajectories.

RESULTS

Survival estimates were lower among women who were weak at baseline for only 65- to 74-year-olds (11.93 vs 16.69 years). Survival estimates were also lower among men who were weak at baseline for only ≥75-year-olds (5.80 vs 7.39 years). Lower strength at baseline (per 0.1 decrement) was significantly associated with mortality (hazard ratio [HR]: 1.10; 95% confidence interval [CI]: 1.01-1.19) for women only. There was a strong independent, longitudinal association between strength decline and early mortality, such that each 0.10 decrease in strength, within participants over time, resulted in a HR of 1.12 (95% CI: 1.00-1.25) for women and a HR of 1.15 (95% CI: 1.04-1.28) for men.

CONCLUSIONS

Longitudinal declines in strength are significantly associated with all-cause mortality in older Mexican Americans.

Handgrip strength is associated with metabolic syndrome among middle-aged and elderly community-dwelling persons

The association of low muscle strength with cardio-metabolic risks remains controversial. The present study included 742 men aged 70 ± 9 years and 937 women aged 70 ± 8 years from a rural village. We examined the cross-sectional relationship between relative muscle strength defined by handgrip strength (HGS)/body weight (BW) ratio, and metabolic syndrome (MetS) based on the modified criteria of the National Cholesterol Education Program's Adult Treatment Panel (NCEP-ATP) III report and its components. Of these, 203 men (27.4%) and 448 women (47.8%) had MetS. In men, increasing quartile of HGS/BW ratio was significantly and independently associated with high waist circumference {odds ratio, 0.31; 95% confidence interval (CI), 0.24-0.41} and elevated triglyceridemia (0.71, 0.59-0.86). In women, it was also significantly and independently associated with high waist circumference (0.41; 0.36-0.48), high blood pressure (0.78; 0.66-0.92), Low HDL-cholesterolemia (0.84; 0.73-0.98) and elevated triglyceridemia (0.65; 0.53-0.79). In both genders, the prevalence of MetS significantly decreased in relation to increasing HGS/BW ratio. After adjustment for age, smoking status, drinking status, LDL-C, estimated glomerular filtration ratio (eGFR), and medication, the respective odds ratio (95% CI) for the quartile of HGS/BW ratio for MetS was 1.00, 0.54 (0.34-0.85), 0.32 (0.19-0.53), and 0.16 (0.09-0.29) in men, and 1.00, 0.76 (0.50-1.16), 0.33 (0.22-0.51), and 0.16 (0.10-0.25) in women. These results suggest that HGS/BW ratio was significantly and negatively associated with an increased risk of cardio-metabolic disorders in Japanese-community dwelling persons.

Neuromuscular dysfunction in type 2 diabetes: underlying mechanisms and effect of resistance training

Diabetic patients are at higher risk of developing physical disabilities than non-diabetic subjects. Physical disability appears to be related, at least in part, to muscle dysfunction. Several studies have reported reduced muscle strength and power under dynamic and static conditions in both the upper and lower limbs of patients with type 2 diabetes. Additional effects of diabetes include a reduction in muscle mass, quality, endurance and an alteration in muscle fibre composition, though the available data on these parameters are conflicting. The impact of diabetes on neuromuscular function has been related to the co-existence of long-term complications. Peripheral neuropathy has been shown to affect muscle by impairing motor nerve conduction. Also, vascular complications may contribute to the decline in muscle strength. However, muscle dysfunction occurs early in the course of diabetes and affects also the upper limbs, thus suggesting that it may develop independently of micro and macrovascular disease. A growing body of evidence indicates that hyperglycaemia may cause an alteration of the intrinsic properties of the muscle to generate force, via several mechanisms. Recently, resistance exercise has been shown to be an effective strategy to counteract the deterioration of muscular performance. High-intensity exercise seems to provide greater benefits than moderate-intensity training, whereas the effect of a power training is yet unknown. This article reviews the available literature on the impairment of muscle function induced by diabetes, the underlying mechanisms, and the effect of resistance training on this defect. Copyright © 2015 John Wiley & Sons, Ltd.

Grip Strength as a Marker of Hypertension and Diabetes in Healthy Weight Adults

INTRODUCTION

Muscle strength may play a role in cardiometabolic disease. We examined the relationship between hand grip strength and diabetes and hypertension in a sample of healthy weight adults.

METHODS

In 2015, we analyzed the National Health and Nutrition Examination Survey 2011-2012 for adults aged ≥20 years with healthy BMIs (between 18.5 and <25) and no history of cardiovascular disease (unweighted n=1,467; weighted n=61,587,139). Hand grip strength was assessed with a dynamometer. Diabetes was based on hemoglobin A1c level and reported diabetes diagnosis. Hypertension was based on measured blood pressure and reported hypertension diagnosis.

RESULTS

Individuals with undiagnosed diabetes compared with individuals without diabetes had lower grip strength (51.9 vs 69.8, p=0.0001), as did individuals with diagnosed diabetes compared with individuals without diabetes (61.7 vs 69.8, p=0.008). Mean grip strength was lower among individuals with undiagnosed hypertension compared with individuals without hypertension (63.5 vs 71.5, p=0.008) as well as among individuals with diagnosed hypertension compared with those without hypertension (60.8 vs 71.5, p<0.0001). In adjusted analyses controlling for age, sex, race, smoking status, and first-degree relative with disease, mean grip strength was lower for undiagnosed diabetes (β=-10.02, p<0.0001) and diagnosed diabetes (β=-8.21, p=0.03) compared with individuals without diabetes. In adjusted analyses, grip strength was lower among individuals with undiagnosed hypertension (β=-6.6, p=0.004) and diagnosed hypertension (β=-4.27, p=0.04) compared with individuals without hypertension.

CONCLUSIONS

Among healthy weight adults, combined grip strength is lower in individuals with diagnosed and undiagnosed diabetes and hypertension.