Gender differences in anthropometric predictors of physical performance in older adults

Mediterranean Diet Combined with Regular Aerobic Exercise and Hemp Protein Supplementation Modulates Plasma Circulating Amino Acids and Improves the Health Status of Overweight Individuals

Plant protein is considered a sustainable health-promoting strategy to prevent metabolic syndrome. Lifestyle changes (including dietary patterns and exercise) have been demonstrated to exert an effect on human health by modulating the biochemical status in humans. The objective of this study was to assess whether supplementation with hemp protein within a Mediterranean diet context together with exercise could help to ameliorate the metabolic statuses of patients prone to developing metabolic syndrome. For this study, 23 patients followed with Mediterranean diet and engaged in aerobic exercise according to the WHO's recommendations, while also being supplemented with hemp protein, for 12 weeks. A comparison of anthropometric, biochemical, and mineral data as well as amino acid values was made between the start and the end of the study, with the subjects acting as their own control group. Statistical analyses included a paired t-test, Wilcoxon paired test, Pearson correlation coefficient, and Sparse Partial Least Squares Discriminant Analysis to evaluate significant differences and correlations among parameters. There were statistically significant changes in total cholesterol, HDL-C (+52.3%), LDL-C (-54.0%), and TAG levels (-49.8%), but not in glucose plasma levels. Following the intervention, plasma concentrations of some amino acids, including α-aminoadipic acid, phosphoethanolamine, and 1-metylhistidine, increased, whereas those of asparagine and alanine declined. Different correlations between amino acids and the other parameters evaluated were reported and discussed. A Mediterranean diet combined with regular aerobic exercise, together with protein supplementation, can highly improve the metabolic parameters and anthropometric parameters of subjects with obesity and impaired glucose levels, ameliorating their health status and likely delaying the development of metabolic syndrome.

Gender Differences in Anthropometric, Functional Capacity Measures and Quality of Life in Individuals with Intellectual and Developmental Disabilities

The aim of the of the current investigation was to investigate the possible differences concerning males and females in anthropometry, body composition, functional capacity, strength and quality of life variables. After obtaining signed informed consent, 37 participants (18 males; 19 females), with mean age of 39.08 and standard deviation of 11.66 years, voluntarily participated in this study. Anthropometry, body composition, functional capacity, strength, and quality of life were assessed using validated and reliable instruments and tests for this population. The males and females were compared using a Mann-Whitney U signed rank test. Significant differences were detected among the following variables, height (p = 0.028), body mass index (p = 0.033), fat mass (p = 0.002), muscle mass (p ≤ 0.001), phase angle (p = 0.005), medicine ball throwing strength (p = 0.010), and peak toque left knee (p = 0.028), with males showing better results in all the variables. The sample in this study showed differences in the anthropometric, composition, and strength variables. Studying this population can help ensure that everyone has equal access to services and adequate support for their personal needs, improving their quality of life.

Thoughts and perspectives on biomechanical numerical models under impacts: Are women forgotten from research?

The present paper explores a series of articles in the literature which deal with impact biomechanics of the head and thorax/abdomen segments, investigating the "sex specific properties/data" used in the studies. Statements in these studies are analyzed and point out, the use of male or female subjects for the developments of finite element models and their validation against experimental data. The present analysis raises the question about "androcentrism," and how biomechanical engineering findings and the design of the derived protecting devices are focused on male subjects.

Field-Based Estimates of Muscle Quality Index Determine Timed-Up-and-Go Test Performance in Obese Older Women

Objective

The muscle quality index (MQI) is associated with numerous health outcomes in adults; however, the effects of distinct MQI on functional capacity in obese older women have not yet been fully investigated. Thus, we investigated the contribution of different muscle quality indices on TUG performance prediction in obese older women. We secondarily evaluated the association between MQI, aerobic capacity performance (Treadmill performance and 6-minute walk test), and obesity indices (BMI, body fat percentage, and neck, waist, and hip circumference).

Methods

Participants included 64 obese older women (mean age 67.05 ± 5.46 years, body fat ≥ 35%). General anthropometric, health history, body composition, treadmill exercise, and functional test (Time up and go) measures were collected. A hydraulic dynamometer was used to assess muscle strength, and Dual Energy X-ray Absorptiometry (DXA) to identify body fat percentage. The field MQI was defined as the highest reading divided by the subject's body mass index (BMI), while the laboratory MQI was obtained by the ratio of grip strength to the entire arm muscle in kilograms measured by DXA. A hierarchical multiple regression was performed to predict TUG-test performance.

Results

An increase in field MQI of one unit is associated with a decrease of 2.59 seconds in the TUG test (β = -0.540; p = 0.004). There was no association between laboratory MQI and TUG performance (β = 0.067; p = 0.712). Furthermore, field MQI displays a positive correlation (p < 0.05) with aerobic capacity performance (6-minute walk test and peak O₂ consumption) and a negative correlation (p < 0.05) with diverse obesity indices (neck and waist circumference, body fat, and BMI).

Conclusion

MQI displayed an important prediction with TUG-test, a positive correlation with aerobic capacity, and a negative correlation with obesity indices.

Impact of Body Composition Parameters on Lung Function in Athletes

Background: Given the potential risk of unhealthy weight management, the monitoring of body composition in athletes is advised. However, limited data reveal how body composition measurements can benefit athlete health and, in particular, respiratory function. The aim of this study is to evaluate the impact of body composition on pulmonary function in a population of adult athletes. Methods: Data from 435 competitive adult athletes regarding body compositions parameters and spirometry are retrospectively analyzed. Results: Our study population consists of 335 males and 100 female athletes. Muscle mass and fat-free mass are significantly and positively associated with forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) in the male and female population, while waist-to-height ratio is negatively associated with FEV1, FVC, and FEV1/FVC in the male population. In multivariable analysis, muscle mass and fat-free mass show significant association with FEV1 and FVC in both males and females (p < 0.05), and waist-to-height ratio is significantly and inversely associated with FEV1 and FVC in males (p < 0.05). Conclusions: Fat-free mass and muscle mass are positively and independently associated with FEV1 and FVC in athletes of both genders, and waist-to-height ratio is inversely associated with FEV1 and FVC only among male athletes. These findings suggest that body composition in athletes may be helpful in monitoring respiratory function.

Association of Handgrip Strength in Various Disabilities in Korean Adults over 50 Years Old: A Nationwide Cross-Sectional Study

Several studies have shown an association between low hand grip strength (HGS) and functional limitations. This study aims to elucidate the association between HGS and functional limitations. We used the nationwide health examination data and included 13,517 Korean adults that were aged ≥ 50 years. We measured HGS using digital dynamometer and the maximum value of the dominant hand was divided into quartiles for the analysis. Functional limitations were assessed by using self-administered questionnaires. We categorized the 24 reported causes of functional limitations into musculoskeletal, cardiometabolic, neuropsychiatric, cancers, and others. In multiple regression analysis, the functional limitations tended to increase as HGS was lowered in both sexes. When analyzing according to the reasons of functional limitations, the ORs for functional limitations due to cardiometabolic problem tended to increase as the HGS decreased in men (p for trend = 0.039). Similar trends were observed in neuropsychiatric problem in women (p for trend = 0.002) and other problems in both men and women (p for trend = 0.014 in men, p for trend = 0.004 in women). No significant trends were observed for musculoskeletal problems and cancer in both men and women. The functional limitations were inversely associated with HGS, which were inconsistent according to different etiologies of functional limitations.

Are sociodemographic and anthropometric variables effective in screening probable and confirmed sarcopenia in community-dwelling older adults? A cross-sectional study

BACKGROUND

Screening for probable and confirmed sarcopenia using sociodemographic and anthropometric indicators can be a practical, cheap, and effective strategy to identify and treat older people susceptible to this condition.

OBJECTIVES

To identify cutoff points for sociodemographic and anthropometric variables in screening probable and confirmed sarcopenia in community-dwelling older adults.

DESIGN AND SETTING

This was a cross-sectional study of community-dwelling older adults in Araranguá, Santa Catarina, Brazil.

METHODS

Sociodemographic (age, education) and anthropometric (weight, height, body mass index [BMI], waist circumference [WC], and dominant calf circumference [DCC]) factors were considered as predictors. The outcomes were probable sarcopenia (reduction in muscle strength assessed by time ≥ 15 s in the five-time sit-to-stand test) and confirmed sarcopenia (reduction in strength and muscle mass). Receiver operating characteristic curve analysis was used to analyze the ability to track sociodemographic and anthropometric variables for sarcopenia.

RESULTS

In 308 older adults, WC > 91 cm in women and age > 69 years in men were useful in screening for probable sarcopenia. The variables age, weight, BMI, WC, and DCC can be used to screen for sarcopenia in older women and men.

CONCLUSION

Sociodemographic and anthropometric variables are simple and accessible tools for sarcopenia screening in older adults.

Cognitive Dispersion Predicts Grip Strength Trajectories in Men but not Women in a Sample of the Oldest Old Without Dementia

Background and Objectives

Grip strength is a reliable marker of biological vitality and it typically demonstrates an expected decline in older adults. According to the common-cause hypothesis, there is also a significant association between cognitive and physical function in older adults. Some specific cognitive functions have been shown to be associated with grip strength trajectories with most research solely focused on cutoff points or mean cognitive performance. In the present study, we examine whether a measure of cognitive dispersion might be more informative. We therefore used an index that quantifies dispersion in cognitive scores across multiple cognitive tests, shown to be associated with detrimental outcomes in older adults.

Research Design and Methods

Using repeated grip strength measures from men and women aged 80 and older, free of dementia in the OCTO-Twin study, we estimated aging-related grip strength trajectories. We examined the association of cognitive dispersion and mean cognitive function with grip strength level and aging-related rate of change, accounting for known risk factors.

Results

Cognitive dispersion was associated with grip strength trajectories in men and the association varied by mean cognitive performance, whereas we found no association in women.

Discussion and Implications

Our results provide evidence of a sex-specific vitality association between cognitive dispersion and aging-related trajectories of grip strength. Our results support the call for integration of sex and gender in health promotion and intervention research.

The sex difference in gait speed among older adults: how do sociodemographic, lifestyle, social and health determinants contribute?

Background

This study explores whether a sex difference in sensitivity to (strength of the association) and/or in exposure to (prevalence) determinants of gait speed contributes to the observed lower gait speed among older women compared to men.

Methods

Data from the Longitudinal Aging Study Amsterdam (LASA) were used. In total 2407 men and women aged 55–81 years were included, with baseline measurements in 1992/2002 and follow-up measurements every 3–4 years for 15/25 years. Multivariable mixed model analysis was used to investigate sex differences in sensitivity (interaction term with sex) and in exposure to (change of the sex difference when adjusted) socio-demographic, lifestyle, social and health determinants of gait speed.

Results

Women had a 0.054 m/s (95 % CI: 0.076 − 0.033, adjusted for height and age) lower mean gait speed compared to men. In general, men and women had similar determinants of gait speed. However, higher BMI and lower physical activity were more strongly associated with lower gait speed in women compared to men (i.e. higher sensitivity). More often having a lower educational level, living alone and having more chronic diseases, pain and depressive symptoms among women compared to men also contributed to observed lower gait speed in women (i.e. higher exposure). In contrast, men more often being a smoker, having a lower physical activity and a smaller personal network size compared to women contributed to a lower gait speed among men (i.e. higher exposure).

Conclusions

Both a higher sensitivity and higher exposure to determinants of gait speed among women compared to men contributes to the observed lower gait speed among older women. The identified (modifiable) contributing factors should be taken into account when developing prevention and/or treatment strategies aimed to enhance healthy physical aging. This might require a sex-specific approach in both research and clinical practice, which is currently often lacking.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02279-7.

Associations between longitudinal trajectories of insomnia symptoms and sleep duration with objective physical function in postmenopausal women: the Study of Women's Health Across the Nation

STUDY OBJECTIVES

Examine the association between trajectories of self-reported insomnia symptoms and sleep duration over 13 years with objective physical function.

METHODS

We utilized data from 1627 Study of Women's Health Across the Nation (SWAN) participants, aged 61.9±2.7 y at the end of the 13-y follow-up. Latent class growth models identified trajectories of insomnia symptoms (trouble falling asleep, frequent night-time awakenings, and/or early-morning awakening) and sleep duration over 13 y. Physical function tests were performed at the end of the 13-y period: 40-ft walk, 4-m walk, repeated chair stand, grip strength, and balance. Multivariable regression analyses examined each physical function measure according to the insomnia symptom or sleep duration trajectory group.

RESULTS

Five insomnia symptom trajectories and two sleep duration trajectories were identified. Women with a consistently high likelihood of insomnia symptoms and women with a decreased likelihood of insomnia symptoms (i.e., improving) had slower gait speed (3.5% slower 40-ft walk [consistently high], 3.7% slower 4-m walk [improving]; each P≤.05) than those with a consistently low likelihood of insomnia symptoms. In contrast, women with a steep increase in the likelihood of insomnia symptoms over time and women with persistent insufficient sleep duration had lower odds of having a balance problem (odds ratio [OR]=0.36 and OR=0.61, respectively; each P<.02) compared to those with a consistently low likelihood of insomnia symptoms and those with persistent sufficient sleep duration, respectively.

CONCLUSION

These results suggest that women's sleep during midlife has important implications for maintaining physical function during the transition into older adulthood.

Comparison of field- and laboratory-based estimates of muscle quality index between octogenarians and young older adults: an observational study

Muscle quality (the ratio of strength to lean muscle mass) might be a better indicator of muscle function than strength alone. Differences in muscle quality index (MQI) between octogenarians and young older adults remain unclear. The aims of the present cross-sectional study were to compare (1) MQI between octogenarians and young older adults, (2) lab versus field-based MQI tools, and (3) determine possible confounding factors affecting MQI in older adults. Compiled data from two cross-sectional studies included 175 younger and older adults (31 men and 144 women) with a mean age of 75.93±9.49 years. Participants with age ≥80 years old were defined as octogenarians (n=79) and <80 years was defined as young older adults (n=96). Laboratory MQI was derived from the ratio of grip strength to arm muscle mass (in kg) measured by dual-energy x-ray absorptiometry. Field-based MQI was quantified from the ratio of grip strength to body mass index (BMI). Octogenarians displayed lower field (P=0.003) and laboratory MQI (P<0.001) as compared with young older adults. There was a strong correlation effect between field MQI and laboratory MQI (P=0.001, R=0.85). BMI (P=0.001), and diabetes mellitus (P=0.001) negatively affected MQI. Women presented lower MQI (P=0.001) values than men. In light of this information, rehabilitation specialists should consider the use of field-based MQI as a tool for evaluation and follow-up of older population.

Quadriceps Lipid Content Has Sex-Specific Associations With Whole-Muscle, Cellular, and Molecular Contractile Function in Older Adults

Increased adiposity is associated with reduced skeletal muscle function in older adults, but the mechanisms underlying this relationship remain unclear. To explore whether skeletal muscle properties track with adiposity, whole-muscle, cellular, and molecular function were examined in relation to adiposity measured at various anatomical levels in healthy older (60-80 years) men and women. Although women had greater absolute and relative body and thigh fat than men, quadriceps muscle attenuation, an index of intramuscular lipid content, was similar between sexes. At the whole-muscle level, greater quadriceps attenuation was associated with reduced knee extensor function in women, but not men. In women, decreased myosin heavy chain I and IIA fiber-specific force was associated with higher intramuscular lipid content, which may be explained, in part, by the reduced myofilament lattice stiffness found in myosin heavy chain IIA fibers. Longer myosin attachment times in myosin heavy chain I fibers from men and women were associated with greater amounts of adipose tissue, suggesting that fat deposits lead to slower myosin-actin cross-bridge kinetics. Our results indicate greater quantities of adipose tissue alter myofilament properties and cross-bridge kinetics, which may partially explain the adiposity-induced decrements in single-fiber and whole-muscle function of older adults, especially women.

Relevance of sex, age and gait kinematics when predicting fall-risk and mortality in older adults

Approximately one-third of elderly people fall each year with severe consequences, including death. The aim of this study was to identify the most relevant features to be considered to maximize the accuracy of a logistic regression model designed for prediction of fall/mortality risk among older people. This study included 261 adults, aged over 65 years. Men and women were analyzed separately because sex stratification was revealed as being essential for our purposes of feature ranking and selection. Participants completed a 3-m walk test at their own gait velocity. An inertial sensor attached to their lumbar spine was used to record acceleration data in the three spatial directions. Signal processing techniques allowed the extraction of 21 features representative of gait kinematics, to be used as predictors to train and test the model. Age and gait speed data were also considered as predictors. A set of 23 features was considered. These features demonstrate to be more or less relevant depending on the sex of the cohort under analysis and the classification label (risk of falls and mortality). In each case, the minimum size subset of relevant features is provided to show the maximum accuracy prediction capability. Gait speed has been largely used as the single feature for the prediction fall risk among older adults. Nevertheless, prediction accuracy can be substantially improved, reaching 70% in some cases, if the task of training and testing the model takes into account some other features, namely, sex, age and gait kinematic parameters. Therefore we recommend considering sex, age and step regularity to predict fall-risk.

Development and validation of an equation to estimate body fat in elderly women

Abstract The purpose of this present study was to develop and validate a prediction equation for body composition assessment using anthropometric measures of elderly women. This is cross-sectional correlational study with 243 older women ± 64.5 years old and body mass index (BMI) ± 28.70 kg/m². For the development of the equation it was utilized the method of hold-out sample validation. The participants were randomly divided into equation development group (96 elderly women) and a group for validation (147 elderly women). Total body mass, height, waist and hip circumferences, ratio waist-hip ratio and BMI were measured. The whole-body dual-energy X-ray absorptiometry (DXA) assessed body composition (percentage of body fat, fat mass, and fat-free mass). The equations were developed using multiple linear regression, with validation by the stepwise method; the comparison of the equations was analyzed by the paired Student's t test and the analysis of residual scores by the method of Blant and Altman. The New Equation presents a strong correlation (R = 0.83) and (R² = 0.69), and a standard error of estimation equals to 3.21% for percentage body fat prediction. The mean difference between the estimations of percentage body fat from DXA and the New Equation was 0.11% (t(0,180); P = 0.850). Therefore, the New Equation had an accuracy of 93.5% and a total error of 1.8%. The body fat estimation in older women using this New Equation based on BMI and age is valid and accurate.

Abdominal obesity, dynapenia and dynapenic-abdominal obesity as factors associated with falls

OBJECTIVE

To investigate whether abdominal obesity, dynapenia and dynapenic-abdominal obesity are associated to the prevalence of single or recurrent falls in older adults.

METHODS

We analyzed data from 1,046 community-dwelling participants of the SABE Study (Saúde, Bem-estar e Envelhecimento/Health, Well-Being and Ageing). Participants were classified as non-dynapenic/non-abdominal obese, abdominal obese only, dynapenic only, and dynapenic-abdominal obese based on waist circumference (>102cm for men and >88cm for women) and handgrip strength (<26kg for men and <16kg for women). Multinomial logistic regression models were ran to determine associations between dynapenia/obesity/dynapenic-abdominal obesity and single/recurring falls, taking non-fallers as reference.

RESULTS

Abdominal obesity (RRR=1.90 95% CI: 1.02-3.55), dynapenia (RRR=1.80 95% CI: 1.02-3.19), and dynapenic-abdominal obesity (RRR=2.06 95% CI: 1.04-4.10) were associated with a single fall. A stronger association for dynapenic-abdominal obesity compared to the other two conditions alone was found. Dynapenia was the unique condition associated with recurrent falls (RRR=2.33, 95% CI: 1.13-4.81).

CONCLUSION

The present findings have important implications for the identification of older adults with a greater chance of falls and can help in the development of rehabilitation strategies. Therefore, abdominal obese, dynapenic, and dynapenic abdominal obese individuals should be target groups for the management of falls and their consequences.

The Association between Frailty and Disability among the Elderly in Rural Areas of Korea

Background: The rapid increase in the elderly population in Korea is associated with an expanded burden of health problems. The purpose of this study was to investigate the association between frailty and physical disability among Koreans using the frailty index, which was developed to assess health conditions in elderly people. Methods: We included 503 elderly people from the Namgaram-II cohort. We used the Korean version of the Kaigo-Yobo checklist as our frailty assessment tool. For the disability assessment tool, we used the Korean version of the 12-item World Health Organization Disability Assessment Schedule (WHODAS-12). We fit multiple linear regression models for men and women for each section. Our models also included variables for musculoskeletal diseases that are known to be associated with frailty, such as sarcopenia, osteoporosis, and radiologic knee osteoarthritis. Results: After correcting for social demographic characteristics, blood profiles, high blood pressure, and diabetes, the Kaigo-Yobo results showed a significant difference in frailty between men (1.53 ± 0.74) and women (2.60 ± 0.77), and WHODAS-12 also showed a significant difference between men (6.59 ± 5.08) and women (15.99 ± 5.70). After correcting for social demographic characteristics, blood profiles, high blood pressure, and diabetes, Kaigo-Yobo and WHODAS-12 were significantly associated with each other among both men (β = 2.667) and women (β = 3.200) (p < 0.001). Conclusions: The study results show an association between frailty and disability among elderly people in rural areas. Therefore, prevention should occur at the pre-frailty stage of a person’s life to prevent further disability. Also, disability welfare programs should be provided to elderly people who present with frailty.

Preliminary study on the effects of movement velocity training of the upper limbs on gait ability in older adults: a nonrandomized controlled trial

Purpose: Movement velocity of the limbs or trunk plays an important determinant of gait speed in older adults. Movement velocity-focused training of the lower limbs or trunk has recently been shown to be an effective intervention to improve gait ability. Because movement velocities of various body regions are significantly correlated, movement velocity training of the upper limbs may also be effective for improving gait speed. Therefore, the purpose of this study was to investigate whether movement velocity training of the upper limbs in a seated position is effective for improving gait ability.

Patients and methods: This study was a nonrandomized controlled trial. The participants were older adults residing in geriatric health service facilities. They were assigned to the movement velocity training of the upper limbs group (n=26) or control group (n=15). The participants in the training group performed exercises (three times per week for 10 weeks) to move the upper limbs as quickly as possible. The outcomes were gait speed, movement velocity, and quadriceps strength. These measurements were performed preintervention and 4, 8, and 10 weeks after intervention.

Results: A significant time–group interaction was found for maximum gait speed and movement velocity of the upper limbs. Bonferroni post-hoc test showed significant improvement in gait speed between preintervention and 10 weeks after intervention in the training group. The movement velocity of the upper limbs was significantly improved between preintervention and 4, 8, and 10 weeks after intervention.

Conclusion: Movement velocity training of the upper limbs showed significant and clinically relevant improvements in maximum gait speed at 10 weeks after intervention. This training is a potentially useful intervention and can be safely performed.

Relationship of Incident Falls with Balance Deficits and Body Composition in Male and Female Community-Dwelling Elders

OBJECTIVE

Sarcopenia and obesity are reported risk factors for falls, although the data are not consistent and most studies do not make sex comparisons. We investigated whether falls were associated with balance, gait, and body composition, and whether these relationships are sex-specific.

DESIGN

Secondary analysis of 4-year follow-up data from of the New Mexico Aging Process Study.

SETTING

Albuquerque, New Mexico.

PARTICIPANTS

307 participants (M, n=122, 75.8 yr. SD5.5; F, n=183, 74.6yr SD6.1).

MEASUREMENTS

Gait and balance were assessed annually using the Tinetti test. Lean body mass (LBM), appendicular skeletal muscle mass (ASM), fat free mass (FFM), total fat mass (FM) were assessed annually by DXA. Falls were assessed using bimonthly falls calendars. Hazard ratios (HR) for 2-point worsening in gait and balance score and falls were calculated by Cox proportional hazard for men and women.

RESULTS

Baseline balance deficits, and not body composition, represented the strongest predictor of falls. For the total balance score, the variables with significant sex interactions were ASM (Male-HR 1.02 95%CI 0.60-1.73; Female-HR 1.92 95%CI 1.05-3.52, p=0.03) and FFM (Male-HR 1.04 95%CI 0.64-1.70; Female-HR 1.91 95%CI 1.12-3.24, p=0.04), after adjustment for age, sarcopenia and physical activity. The body composition relationship with balance deficits was U-shaped with the strongest predictors being low LBM in males and high FM in females.

CONCLUSIONS

Specific body composition components and balance deficits are risk factors for falls following sex-specific patterns. Sex differences need to be explored and considered in interventions for worsening balance and falls prevention.

Knee extension rate of velocity development affects walking performance differently in men and women

PURPOSE

Acceleration capacity affects physical function, but whether it differentially affects men versus women or weak versus strong individuals is less known. We investigated whether knee extension rate of velocity development (RVD, a measure of acceleration) is associated with walking performance independent of peak torque and whether the relationships differ in men versus women and in weak versus strong individuals.

METHODS

Relationships of RVD with walking performance were assessed in 326 women and 365 men aged 26-96 years enrolled in the Baltimore Longitudinal Study of Aging. Tests included knee extension peak torque and RVD assessed during a 180°·s^-1 isokinetic strength test and four walking performance measures (usual-paced and fast-paced 6 m walks and 2.5 min usual-paced and 400 m fast-paced walks). Sex-stratified linear regression models were adjusted for age, race, height, appendicular lean mass, fat mass, peak torque, knee pain, and RVD*peak torque interaction.

RESULTS

In men, RVD was not independently associated with any walking performance measure (p > 0.05), and, for the 6 m-usual walk only, there was a significant RVD*peak torque interaction (p < 0.0001). In women, RVD was independently associated with usual-paced walks (p < 0.05) and there were significant RVD ∗ peak torque interactions for all measures. Strength-specific analyses indicated that RVD was most associated with performance among weaker individuals.

CONCLUSION

RVD is associated with walking performance in women, but less in men, and is most related to performance when strength is low. Strategies to accomplish motor tasks may be sex-specific. Future studies are needed to understand the mechanisms underlying such sex differences.

Reduced body weight or increased muscle quality: Which is more important for improving physical function following exercise and weight loss in overweight and obese older women?

The purpose of this study was to examine the relative contributions of changes in muscle quality and body composition to changes in lower-extremity physical function (LEPF) following a 6-month exercise and weight loss intervention in overweight and obese older women. Thirty-eight overweight and obese (BMI = 30.0 ± 4.4 kg/m²) older (age = 69.3 ± 4.1 y) women completed 6 months of multicomponent exercise (cardiorespiratory, resistance, balance and flexibility training) and weight loss (hypocaloric diet that reduced energy intake by ~500 kcal/d). Body composition was measured via dual-energy X-ray absorptiometry and muscle quality (N-m/kg) was defined as maximal concentric isokinetic knee torque divided by upper-leg lean mass. The standardized scores of four objective measures of physical function were summed to yield a composite LEPF Z-score. At 6 months, there were significant reductions in body weight (-9.6 ± 3.5%, p < 0.01), absolute fat mass (-6.8 ± 2.4 kg, p < 0.01) and relative adiposity (-4.9 ± 2.1%, p < 0.01). There were also improvements in both muscle quality (+1.6 ± 1.8 N-m/kg, p < 0.01) and individual measures of LEPF (11-57%, p < 0.01). Multivariate linear regression indicated that increased muscle quality was the strongest independent predictor of an improvement in LEPF Z-score (standardized β = 0.64, p < 0.01) and explained 34% of the variance. A reduction in body weight also predicted an improvement in LEPF, independent of the change in muscle quality. In conclusion, muscle quality can be increased in the presence of clinically meaningful weight loss, and is the primary determinant of improved physical function in overweight/obese older women.

Knee extension rate of torque development and peak torque: associations with lower extremity function

BACKGROUND

With aging, the ability to generate muscle force decreases, contributing to declines in physical functions such as walking. While most studies assess muscle force by peak torque, the rate of torque development (RTD) reflects a dynamic component of muscle performance that is important for physical function. Using data from the Baltimore Longitudinal Study of Aging, we assessed whether RTD adds significantly to peak torque in associations with lower extremity performance. If so, RTD may help identify weak older adults for screening and intervention.

METHODS

We assessed associations of RTD and peak torque with physical performance independent of demographics, BMI, body composition, and each other in 1089 Baltimore Longitudinal Study of Aging participants (49.7% women; aged 26 to 96 years; women, 64.0 ± 13.8 years; men, 68.4 ± 14.4 years). Peak torque was assessed by isometric and 30 deg/s isokinetic knee extension tests. Peak RTD was operationalized as the maximum torque-time slope among successive 50 ms epochs over the first 3 s of a test of knee extension isometric strength, with the knee joint positioned at 120 deg of flexion. A battery of lower extremity performance tests included gait speed during a 6 m walk at usual and fast pace (6 m usual and fast), time to complete a 400 m walk at fast pace (400 m), distance covered in a 2.5 min walk at normal pace (2.5 min), time to complete 5 and 10 chair stands, and two summary tests of lower extremity performance. Sex-stratified generalized linear regression models were adjusted for age, race, BMI, appendicular lean mass, and whole body fat mass.

RESULTS

In men, independent of either measure of peak torque and cofactors, RTD was a significant (P < 0.05) predictor of all lower extremity performance tests except the 400 m and 2.5 min walks. In women, independent of peak torque, RTD was only a significant independent correlate of the 6 m fast walk (P < 0.001).

CONCLUSIONS

RTD independently contributes to physical functions in men but less in women. The mechanisms underlying the sex difference are unclear and require further study.

The Need for Standardized Assessment of Muscle Quality in Skeletal Muscle Function Deficit and Other Aging-Related Muscle Dysfunctions: A Symposium Report

A growing body of scientific literature suggests that not only changes in skeletal muscle mass, but also other factors underpinning muscle quality, play a role in the decline in skeletal muscle function and impaired mobility associated with aging. A symposium on muscle quality and the need for standardized assessment was held on April 28, 2016 at the International Conference on Frailty and Sarcopenia Research in Philadelphia, Pennsylvania. The purpose of this symposium was to provide a venue for basic science and clinical researchers and expert clinicians to discuss muscle quality in the context of skeletal muscle function deficit and other aging-related muscle dysfunctions. The present article provides an expanded introduction concerning the emerging definitions of muscle quality and a potential framework for scientific inquiry within the field. Changes in muscle tissue composition, based on excessive levels of inter- and intra-muscular adipose tissue and intramyocellular lipids, have been found to adversely impact metabolism and peak force generation. However, methods to easily and rapidly assess muscle tissue composition in multiple clinical settings and with minimal patient burden are needed. Diagnostic ultrasound and other assessment methods continue to be developed for characterizing muscle pathology, and enhanced sonography using sensors to provide user feedback and improve reliability is currently the subject of ongoing investigation and development. In addition, measures of relative muscle force such as specific force or grip strength adjusted for body size have been proposed as methods to assess changes in muscle quality. Furthermore, performance-based assessments of muscle power via timed tests of function and body size estimates, are associated with lower extremity muscle strength may be responsive to age-related changes in muscle quality. Future aims include reaching consensus on the definition and standardized assessments of muscle quality, and providing recommendations to address critical clinical and technology research gaps within the field.

Effect of age and sex on jumping mechanography and other measures of muscle mass and function

OBJECTIVES

Sarcopenia increases falls and fracture risk. Sarcopenia clinical trials require robust quantitative tools to evaluate muscle function; jumping mechanography (JM) is likely one such tool. However, US data comparing JM with traditional tests across the lifespan is limited. This study evaluated the effect of age and sex on JM compared with traditional function tests and lean mass.

METHODS

US adults (213 women/119 men; mean age 65.4 years, range 27-96) performed functional tests including JM, Short Physical Performance Battery (SPPB) and grip strength (GS). Appendicular lean mass (ALM) was measured using DXA.

RESULTS

Men had higher relative jump power [mean (SD) 28.5 (10.52) vs. 21.9 (7.11) W/kg], GS [35.5 (9.84) vs. 22.7 (6.98) kg] and ALM/ht(2) [8.25 (1.35) vs. 6.99 (1.38) kg/m2] (all p<0.0001); no difference was observed for SPPB components. JM parameters were more strongly correlated with age than traditional tests (R2=0.38-0.61 vs. R2=0.01-0.28) and weakly with GS and chair rise time (R2=0.30-0.36).

CONCLUSION

JM parameters are correlated with GS and chair rise time and demonstrate stronger correlations with age. JM shows promise as a valuable tool to evaluate and monitor interventions for sarcopenia as it could potentially detect change in muscle function more precisely than existing tools.

Sex-specific relationships of physical activity, body composition, and muscle quality with lower-extremity physical function in older men and women

OBJECTIVE

This study aims to determine the sex-specific relationships of physical activity, body composition, and muscle quality with lower-extremity physical function in older men and women.

METHODS

Seventy-nine community-dwelling men (n = 39; mean [SD] age, 76.1 [6.2] y; mean [SD] body mass index, 27.3 [3.8] kg/m(2)) and women (n = 40; mean [SD] age, 75.8 [5.5] y; mean [SD] body mass index, 27.0 [3.8] kg/m(2)) were assessed for physical activity via questionnaire, body composition via dual-energy x-ray absorptiometry scanning, leg extension power using the Nottingham power rig, and muscle quality (W/kg; the ratio of leg extension power [W] to lower-body mineral-free lean mass [kg]). A composite measure of physical function was obtained by summing Z scores from the 6-minute walk, 8-ft up-and-go test, and 30-second chair-stand test.

RESULTS

As expected, men had significantly greater levels of physical activity, lower adiposity, greater lean mass, higher leg extension power, and greater muscle quality compared with women (all P < 0.05). In linear regression analyses, muscle quality and physical activity were the strongest predictors of lower-extremity physical function in men and independently explained 42% and 29% of the variance, respectively. In women, muscle quality (16%) and percent body fat (12%) were independent predictors after adjustment for covariates.

CONCLUSIONS

Muscle quality is the strongest predictor of lower-extremity physical function in men and women, but sex impacts the importance of physical activity and adiposity. These findings suggest that older men and women may benefit from different intervention strategies for preventing physical disability and also highlight the importance of weight management for older women to preserve physical function.

Body composition as a frailty marker for the elderly community

Background

Body composition (BC) in the elderly has been associated with diseases and mortality; however, there is a shortage of data on frailty in the elderly.

Objective

To investigate the association between BC and frailty, and identify BC profiles in nonfrail, prefrail, and frail elderly people.

Methods

A cross-sectional study comprising 235 elderly (142 females and 93 males) aged ≥65 years, from the city of Amparo, State of São Paulo, Brazil, was undertaken. Sociodemographic and cognitive features, comorbidities, medication, frailty, body mass index (BMI), muscle mass, fat mass, bone mass, and fat percent (%) data were evaluated. Aiming to examine the relationship between BC and frailty, the Mann–Whitney and Kruskal–Wallis nonparametric tests were applied. The statistical significance level was P<0.05.

Results

The nonfrail elderly showed greater muscle mass and greater bone mass compared with the prefrail and frail ones. The frail elderly had greater fat % than the nonfrail elderly. There was a positive association between grip strength and muscle mass with bone mass (P<0.001), and a negative association between grip strength and fat % (P<0.001). Gait speed was positively associated with fat mass (P=0.038) and fat % (P=0.002). The physical activity level was negatively associated with fat % (P=0.022). The weight loss criterion was positively related to muscle mass (P<0.001), bone mass (P=0.009), fat mass (P=0.018), and BMI (P=0.003). There was a negative association between fatigue and bone mass (P=0.008).

Discussion: Frailty in the elderly was characterized by a BC profile/phenotype with lower muscle mass and lower bone mass and with a higher fat %. The BMI was not effective in evaluating the relationship between BC and frailty. The importance of evaluating the fat % was verified when considering the tissue distribution in the elderly BC.

Differences in physical function by body mass index in elderly Japanese individuals: The Fujiwara-kyo Study

OBJECTIVE

This study examined differences in physical function according to body mass index (BMI) in elderly Japanese individuals.

METHODS

Participants (1754 men and 1795 women aged ≥65 years) were divided into the following five BMI groups: low BMI (≤20.0), low-medium BMI (20.1-22.5), medium BMI (22.6-25.0), medium-high BMI (25.1-27.5) and high BMI (≥27.6). Physical function was measured according to BMI and sex, and associations between BMI and physical function were examined.

RESULTS

Compared with the medium BMI group, handgrip strength (HGS), knee extension torque (KET), and knee flexion torque (KFT) were significantly lower in both sexes in the low BMI group, while KET and KFT were significantly higher among men in the high BMI group. One-leg standing time (OLST) with open eyes was significantly shorter among men in the high BMI group than in the medium BMI group. The high BMI group was significantly inferior to the medium BMI group in 10m gait time (10MGT), OLST, and maximum one-step length to height ratio among women. All physical functions, except for 10MGT in men, were associated with BMI adjusted age and/or sex. Muscle strength showed a positive association with BMI in both sexes. There was a stronger association between BMI and physical performance in women compared to men.

CONCLUSION

We found that BMI influences a variety of factors related to muscle strength and physical performance. Our findings may help contribute to the prevention of mobility impairments in elderly Japanese individuals.

Effect of wrist angle on median nerve appearance at the proximal carpal tunnel

This study investigated the effects of wrist angle, sex, and handedness on the changes in the median nerve cross-sectional area (MNCSA) and median nerve diameters, namely longitudinal diameter (D1) and vertical diameter (D2). Ultrasound examination was conducted to examine the median nerve at the proximal carpal tunnel in both dominant and nondominant hands of men (n = 27) and women (n = 26). A total of seven wrist angles were examined: neutral; 15°, 30°, and 45° extension; and 15°, 30°, and 45° flexion. Our results indicated sexual dimorphism and bilateral asymmetry of MNCSA, D1 and D2 measurements. MNCSA was significantly reduced when the wrist angle changed from neutral to flexion or extension positions. At flexion positions, D1 was significantly smaller than that at neutral. In contrast, at extension positions, D2 was significantly smaller than that at neutral. In conclusion, this study showed that MNCSA decreased as the wrist angle changed from neutral to flexion or extension positions in both dominant and nondominant hands of both sexes, whereas deformation of the median nerve differed between wrist flexion and extension.

Effects of a community-based multimodal exercise program on physical function and quality of life in cancer survivors: a pilot study

The purpose of this single-arm pilot study was to examine the effects of a community-based multimodal exercise program on: physical function (Timed-Up-and-Go [TUG], 6-min walk test [6MWT], leg and chest press strength, and functional reach [FR]); and quality of life, QoL [FACT-G]), in cancer survivors. Fifty-nine cancer survivors (91.5% female; mean age 59 ± 12 years) completed supervised exercise training for 90 min twice weekly for 12 weeks. Exercise training consisted of 30 min of each of the following: (1) aerobic conditioning; (2) resistance training; and (3) balance and flexibility training. Pre-post-outcome measures were compared for statistically significant differences (p < 0.01) and were related to the International Classification of Functioning, Disability and Health Model. Effect sizes (ES), minimal clinically important differences, and minimal detectable change at 90% confidence intervals were calculated. Participants decreased TUG time by 21.1% and walked 15.5% farther during 6-MWT (p < 0.001). Leg and chest press strength increased by 34.5% and 32.7%, respectively (p < 0.001). FR increased by 15.1% (p < 0.001). Significant improvements for physical well-being (13.9%), emotional well-being (6.7%), functional well-being (13.0%), and total well-being (9.6%) were found (p < 0.01). Improvements in physical function and QoL showed "moderate to large" ESs indicating improvements in physical function and QoL are clinically meaningful.

Relationship between strength, function, and quality of life in older adults with chronic lung disease: is there an influence of gender?

PURPOSE

Chronic lung disease results in impaired quality of life (QOL) linked to loss of muscular strength and functional ability. Inequalities in strength and function may place women at greater risk than men. This study evaluated the influence of gender on the relationship between muscular strength, functional ability, and QOL.

METHODS

Older adults (N = 40) referred to a pulmonary rehabilitation program completed assessment of upper body and lower body strength, functional ability, and QOL. To compensate for gender differences, strength was normalized for body mass.

RESULTS

Strength was greater in men than in women (P < .001). No gender differences were observed for function. Men perceived better QOL related to physical function (score: 39.3 ± 3.3 vs 27.1 ± 2.1, P < .01) and social function (score: 58.0 ± 5.8 vs 41.6 ± 4.0, P < .05). In men, strength was related directly to QOL through physical function (r = 0.53, P < .05) and social function (r = 0.52, P < .05), and functional ability had no relationship to QOL. In women, strength was related to functional ability (r = 0.57, P < .05), and functional ability was directly related to QOL through physical function (r = 0.46, P < .05), and social function (r = 0.59, P < .01).

CONCLUSIONS

Functional ability mediates the relationship between strength and QOL in women, while in men strength is directly related to QOL. These gender-specific pathways to QOL may be of importance to clinicians planning interventions for older adults with chronic lung disease.

Association of thigh muscle strength with knee symptoms and radiographic disease stage of osteoarthritis: data from the Osteoarthritis Initiative

OBJECTIVE

To determine whether thigh muscle strength differs between symptomatic and asymptomatic knees, and/or different radiographic strata of knee osteoarthritis (KOA).

METHODS

Isometric extensor and flexor strength were analyzed in 3,809 Osteoarthritis Initiative participants (2,201 women and 1,608 men) with central radiographic Kellgren/Lawrence (K/L) grade readings. Isometric strength measurements were stratified by radiographic disease status (K/L grades 0, 1, 2, and 3/4) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scores. Age-adjusted, separate-slopes analysis of covariance models was used to compare strength between "symptomatic" (WOMAC score range 5-20) and "asymptomatic" (WOMAC score = 0) legs within and across K/L grade strata. Exploratory analyses focused on strength normalized to body weight and symptom frequency.

RESULTS

Isometric strength was significantly lower in symptomatic than in asymptomatic legs: -11 to -13% for extensor strength and -7 to -16% for flexor strength (P < 0.0001 for both) in men, and -9 to -17% (P = 0.029) for extensor strength, and -10 to -21% (P = 0.049) for flexor strength in women. Similar observations were made for pain frequency strata. Extensor and flexor strength were not significantly different across K/L grade strata in asymptomatic legs in either sex (P ≥ 0.12). However, strength normalized to body weight was lower at higher K/L grades in both sexes (P ≤ 0.02) because the body mass index was greater in participants with more advanced radiographic disease.

CONCLUSION

Knee symptoms (i.e., pain) appear to be the relevant determinant of isometric knee extensor and flexor strength in KOA, whereas no direct association between strength and radiographic severity was observed. These findings suggest that the reduction in thigh muscle strength in KOA is related to pain but not to the structural (radiographic) disease status.

Relationship between age and elite marathon race time in world single age records from 5 to 93 years

BACKGROUND

The aims of the study were (i) to investigate the relationship between elite marathon race times and age in 1-year intervals by using the world single age records in marathon running from 5 to 93 years and (ii) to evaluate the sex difference in elite marathon running performance with advancing age.

METHODS

World single age records in marathon running in 1-year intervals for women and men were analysed regarding changes across age for both men and women using linear and non-linear regression analyses for each age for women and men.

RESULTS

The relationship between elite marathon race time and age was non-linear (i.e. polynomial regression 4(th) degree) for women and men. The curve was U-shaped where performance improved from 5 to ~20 years. From 5 years to ~15 years, boys and girls performed very similar. Between ~20 and ~35 years, performance was quite linear, but started to decrease at the age of ~35 years in a curvilinear manner with increasing age in both women and men. The sex difference increased non-linearly (i.e. polynomial regression 7(th) degree) from 5 to ~20 years, remained unchanged at ~20 min from ~20 to ~50 years and increased thereafter. The sex difference was lowest (7.5%, 10.5 min) at the age of 49 years.

CONCLUSION

Elite marathon race times improved from 5 to ~20 years, remained linear between ~20 and ~35 years, and started to increase at the age of ~35 years in a curvilinear manner with increasing age in both women and men. The sex difference in elite marathon race time increased non-linearly and was lowest at the age of ~49 years.

Biomarkers of muscle quality: N-terminal propeptide of type III procollagen and C-terminal agrin fragment responses to resistance exercise training in older adults

BACKGROUND

N-terminal peptide of procollagen type III (P3NP) and C-terminal agrin fragment (CAF) are circulating biomarkers that are related to lean body mass in older adults. P3NP is a circulating marker reflective of muscular structural remodeling while CAF is a circulating marker of neuromuscular remodeling. As resistance exercise is an established intervention that can effectively improve muscle quality, we sought to evaluate circulating biomarker changes corresponding to a resistance exercise intervention in older adults.

METHODS

Twenty-three older adults (aged 61 to 85 years) were randomized into an intervention (6-week resistance training) or control group. Resting circulating P3NP, CAF, lean body mass (LBM), muscle cross-sectional area (CSA), muscle strength, and muscle quality were determined at baseline and after the intervention or control period by enzyme-linked immunosorbent assay, dual-energy X-ray absorptiometry, ultrasound, leg extension, and relative strength, respectively. Changes in circulating biomarkers and measures of muscle mass and quality were evaluated with repeated-measures analysis of variance; clinical interpretations were made with magnitude-based inferences, and relationships between variables were evaluated with bivariate correlations.

RESULTS

The short-term resistance exercise intervention was effective at improving muscle quality by 28 % (p < 0.001) despite no significant changes in lean body mass. Baseline circulating P3NP was somewhat lower in older women (4.15 ± 1.9 ng/mL) compared with older men (4.81 ± 2.1 ng/mL). The exercise intervention tended to increase circulating P3NP (baseline = 4.53 ± 1.80 to post = 4.88 ± 1.86) and was significantly correlated with changes in LBM (r = 0.422, p = 0.045). At baseline, women (3.91 ± 1.12 pg/mL) had somewhat higher circulating CAF than men (3.47 ± 1.37 pg/mL). Circulating CAF increased by 10.4 % (3.59 to 4.00 pg/ml) in older adults following 6 weeks of resistance exercise training. Changes in circulating CAF were significantly related to changes in CSA of the vastus lateralis (r = 0.542, p = 0.008).

CONCLUSIONS

Assessment of P3NP and CAF from blood samples may provide minimally invasive and clinically informative measures of skeletal muscle status in older adults. Circulating CAF appears to increase in response to short-term resistance exercise training in older adults to a clinically meaningful magnitude. Changes in circulating P3NP in response to the intervention were less clear but appear to reflect muscle hypertrophy. Further research is needed to elucidate whether P3NP, CAF, or other biomarkers can reflect muscle qualitative adaptations with larger and longer studies.

Impact of body mass index on the relationship between muscle quality and physical function in older women

OBJECTIVES

To investigate the impact of body mass index (BMI) (normal weight, overweight, obese) on the relationship between muscle quality (MQ) and physical function in community-dwelling older women.

DESIGN

Cross-sectional study.

SETTING

University research laboratory.

PARTICIPANTS

Community-dwelling older women (n = 94, 73.6 ± 5.4 y) stratified by BMI (normal weight: 20.0-24.9 kg/m2; overweight: 25.0-29.9 kg/m2; obese: ≥ 30.0 kg/m2).

MEASUREMENTS

Body mass index using height and weight, leg extension power via the Nottingham power rig, body composition using dual-energy X-ray absorptiometry, and physical function (6-minute walk, 8-foot up-and-go, 30-second chair stand). Muscle quality was defined as leg power (watts) normalized for lower-body mineral-free lean mass (kg).

RESULTS

Following adjustments for covariates, muscle quality was significantly higher in women of normal BMI compared to overweight (10.0 ± 0.4 vs. 8.7 ± 0.4 watts/kg, p = 0.03). Muscle quality was a significant predictor of performance on the 6-minute walk and 8-foot up-and-go in normal and overweight women (all p < 0.05) and performance on the 30-second chair stand in normal and obese women (both p < 0.05). Body mass index did not significantly impact the association between MQ and physical function (all p > 0.05).

CONCLUSIONS

Muscle quality varies by BMI, yet the relationship to physical function is not significantly different across BMI groups. The results imply that interventions that increase MQ in older women may improve physical function, regardless of BMI.

Muscle Quality in Older Adults

The population of older adults in the United States is steadily growing and identifying factors that contribute to healthy aging is a public health priority. Changes in body composition are a hallmark of the aging process and have been implicated in the loss of physical function among older adults. In particular, age-related declines in muscle strength and power occur at a faster rate than the loss of muscle mass (sarcopenia), and this suggests a decrease in muscle quality of older adults. Muscle quality has traditionally been defined as muscle function (strength or power) per unit of muscle size (mass or cross-sectional area) and a growing body of literature suggests that lower body muscle quality may be critical for maintaining functional independence with age. However, the literature regarding the definition of muscle quality and its relationship with health outcomes in older adults has not been adequately reviewed. Thus, the aim of this report is to highlight the contemporary literature regarding age-related changes in muscle quality and its relationship with health outcomes in community-dwelling older adults.