Sarcopenic obesity does not impair lower limb strength and physical performance in sufficiently active older adults: a cross-sectional study.

This study investigated the associations of sarcopenic obesity (SO) with muscle strength and physical performance in sufficiently active older adults. Data from 72 older sarcopenic obese adults classified as sufficiently active were analyzed. Participants were categorized into four groups based on sex and SO status. Muscle strength/physical performance tests were compared using independent sample t-tests. Multiple linear regression and binary logistic regression were performed to examine the associations between SO and muscle strength and physical performance, adjusting for confounding variables. Only handgrip strength showed differences between SO groups, regardless of sex (p < 0.05). SO negatively explained the variability of handgrip strength (p < 0.05). An increase in handgrip strength values was associated with a decrease in the chances of older adults being classified as SO (p < 0.05). The findings suggest that even with SO, sufficiently active older adults did not present a significant reduction in muscle strength in the lower limbs and physical performance.

Optimizing outdoor fitness equipment training for older adults: Benefits and future directions for healthy aging.

Regular physical activity is vital for the health and disease prevention of older adults. Outdoor fitness equipment has gained popularity for natural exercise spaces among middle-aged and older individuals. This narrative review demonstrates that these programs have the potential to improve cardiovascular health, muscle strength, flexibility, balance, and reduce falls, while also enhancing quality of life, alleviating depression and anxiety, and boosting self-esteem. However, our understanding is hindered by limited rigorous experimental studies. Future directions include implementing standardized measurements, conducting long-term studies, and addressing equipment limitations to enable better adjustment of training intensity and promote correct postures on machines. New, more rigorous research is needed to comprehensively understand the psychophysiological and social effects on health. Additionally, suggested modifications could render the machines more effective and safer. The primary objective is to enhance this type of machinery to encourage its use in outdoor spaces, thus aiding adults and older individuals in achieving overall health and enjoying a healthy aging process.

Characteristics of resistance training-based protocols in older adults with sarcopenic obesity: a scoping review of training procedure recommendations.

Background: Sarcopenic obesity (SO) is a clinical and functional disease characterized by the coexistence of obesity and sarcopenia. Resistance training (RT) characteristics for older adults with sarcopenia or obesity are already well established in the scientific literature. Nonetheless, we still do not know how detailed the RT protocols are described for older adults with SO. Therefore, we aimed to analyze the characteristics of RT programs, including each of their variables, recommended for older adults with SO. Methods: This is a scoping review study that was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis for Scoping Reviews. The search was carried out until November 2022 in PubMed/MEDLINE, EMBASE, Cochrane Library, Web of Science, Scopus, LILACS, Google Scholar, and medRxiv databases. The studies included SO diagnosis and RT as an intervention strategy. The RT variables analyzed were as follows: exercise selection, the volume of sets, the intensity of load, repetition cadence, rest interval between sets, and weekly frequency. Results: A total of 1,693 studies were identified. After applying the exclusion criteria, 15 studies were included in the final analysis. The duration of the RT intervention ranged from 8 to 24 weeks. All studies included full-body routines, with single/multi-joint exercises. Regarding the volume of sets, some studies fixed it in three sets, whereas others varied between one and three sets. The load was reported by repetition range and the weight lifted, elastic-band color/resistance, percentage of one repetition maximum, or perceived exertion scale. Repetition cadence was fixed in some studies, while it was self-selected between concentric and eccentric phases in others. The interval between sets of rest varied from 30 to 180 s. All studies reported progression overload during the interventions. Not all studies reported how the exercise selection, repetition cadence, and rest interval were made. Conclusion: The characteristics of RT protocols and their variables prescribed in the literature for older adults with SO were mapped. The lack of detail on some training variables (i.e., exercise selection, repetition cadence, and rest interval) was identified. RT protocols are heterogeneous and described only partially among studies. The recommendations for RT prescription details in older adults with SO are provided for future studies. Systematic review registration: https://osf.io/wzk3d/.

Handgrip strength conditional tolerance regions suggest the need for personalized sarcopenia definition: an analysis of the American NHANES database.

BACKGROUND: Handgrip strength (HGS) is a well-established clinical biomarker that assesses functional capacity in older populations. In addition, HGS is a diagnostic tool that forecasts aging health conditions, such as sarcopenia. AIMS: This paper provides HGS statistical tolerance regions and presents the need to establish HGS reference values according to patients' characteristics. METHODS: For this purpose, we used a conditional tolerance algorithm for HGS, and we observed the tolerances regions in different age strata and sex of non-sarcopenic individuals from the National Health and Nutrition Examination Survey (NHANES, wave 2011-2012). RESULTS AND DISCUSSION: Our results have critical implications for sarcopenia, since conventional and available HGS cut-offs do not consider age range. CONCLUSIONS: This paper offers new perspectives on the evolution of traditional definitions of sarcopenia according to the principles of precision medicine.

Moderate Physical Activity Reduces the Odds of Sarcopenia in Community- dwelling Older Women: A Cross-sectional Study.

INTRODUCTION: The time spent in different physical activity (PA) intensities is associated with sarcopenia risk for community-dwelling older women. AIM: To evaluate the role of sitting time and physical activity (PA) level as predictors of sarcopenia odds. METHODS: In a cross-sectional study, physically independent older women (n = 67) performed the six-minute walk test to identify functional limitation (≤ 400 m). Sedentary time (as sitting time) and PA (light, moderate and vigorous) were obtained with the International Physical Activity Questionnaire (IPAQ). Sarcopenia was diagnosed as recommended by the Society of Sarcopenia, Cachexia and Wasting Disorders (SCWD). Sarcopenia odds (low muscle mass and functional limitation) was predicted by binary logistic regression, considering the weekly sitting time and PA as independent variables. RESULTS: Sarcopenia prevalence was 7.5% (n = 5), with functional limitation present in 38.8% (n = 26), and low muscle mass in 22.4% (n = 15). The predictive model (p = 0.014) involved moderate PA as the only significant predictor (OR = 0.999; p = 0.005; 95% CI: 0.998-1.000) of functional limitation. Moderate PA prevents sarcopenia odds. Each weekly hour of moderate PA decreased sarcopenia odds by 6%. CONCLUSION: Time spent in moderate PA can prevent sarcopenia.

Multicompartment body composition analysis in older adults: a cross-sectional study.

BACKGROUND: During aging, changes occur in the proportions of muscle, fat, and bone. Body composition (BC) alterations have a great impact on health, quality of life, and functional capacity. Several equations to predict BC using anthropometric measurements have been developed from a bi-compartmental (2-C) approach that determines only fat mass (FM) and fat-free mass (FFM). However, these models have several limitations, when considering constant density, progressive bone demineralization, and changes in the hydration of the FFM, as typical changes during senescence. Thus, the main purpose of this study was to propose and validate a new multi-compartmental anthropometric model to predict fat, bone, and musculature components in older adults of both sexes. METHODS: This cross-sectional study included 100 older adults of both sexes. To determine the dependent variables (fat mass [FM], bone mineral content [BMC], and appendicular lean soft tissue [ALST]) whole total and regional dual-energy X-ray absorptiometry (DXA) body scans were performed. Twenty-nine anthropometric measures and sex were appointed as independent variables. Models were developed through multivariate linear regression. Finally, the predicted residual error sum of squares (PRESS) statistic was used to measure the effectiveness of the predicted value for each dependent variable. RESULTS: An equation was developed to simultaneously predict FM, BMC, and ALST from only four variables: weight, half-arm span (HAS), triceps skinfold (TriSK), and sex. This model showed high coefficients of determination and low estimation errors (FM: R2adj: 0.83 and SEE: 3.16; BMC: R2adj: 0.61 and SEE: 0.30; ALST: R2adj: 0.85 and SEE: 1.65). CONCLUSION: The equations provide a reliable, practical, and low-cost instrument to monitor changes in body components during the aging process. The internal cross-validation method PRESS presented sufficient reliability in the model as an inexpensive alternative for clinical field use.

Association of minimally processed and ultra-processed food daily consumption with obesity in overweight adults: a cross-sectional study.

Introduction: Introduction: food type represents higher odds of having obesity (OB), especially in overweight (OW) subjects. Minimally and ultra-processed foods can be associated with the odds of having OB in OW subjects. Objective: to investigate the association of minimally and ultra-processed food consumption with OB in OW adults. Methods: we included 15,024 participants (9,618 OW [25.0-29.9 kg/m2], 5,406 OB [≥ 30 kg/m2]) with ages ranging from 18 to 59 years from the 2019 baseline survey of the Surveillance of Risk Factors and Protection for Chronic Diseases by Telephone Survey (VIGITEL, Brazil). Minimally and ultra-processed food daily consumption scores and confounding variables (age, sex, scholarly, physical activity, hypertension, and diabetes) were measured. Binary logistic regression analyzes the association of minimally and ultra-processed food consumption scores with OB (odds ratio [OR]). Results: minimally processed food consumption score quartiles (1st = 1[food-score/day]; 2nd = 6[food-score/day]; 3rd = 7[food-score/day]; 4th = 8[food-score/day]) presented higher values compared to ultra-processed food (1st = 1[food-score/day]; 2nd = 1[food-score/day]; 3rd = 2[food-score/day]; 4th = 4[food-score/day]). For each score of minimally processed food consumed, there was a -5.9 % odds of OB. Thus, the higher quartile (4th) of minimally processed food consumption score represents less odds of OB (OR: -47.2 %; p < 0.001). Each ultra-processed food score consumed presented odds of 3.7 % of OB. Therefore, higher consumption of ultra-processed food (4th quartile) shows higher odds of OB (OR: +14.8 %; p < 0.001). All associations remained significatively even after being adjusted by the confounders. Conclusion: the consumption scores of minimally processed and ultra-processed foods presented a magnitude capable of impacting OW adults' odds of OB, even when controlled by sociodemographic factors, physical activity, hypertension, and diabetes.

Introducción: Introducción: el tipo de alimentación representa una mayor probabilidad de tener obesidad (OB), especialmente en sujetos con sobrepeso (SO). Los alimentos mínimamente procesados y ultraprocesados se pueden asociar con las probabilidades de tener OB en sujetos con SO. Objetivo: investigar la asociación del consumo de alimentos mínimamente procesados y ultraprocesados con la OB en adultos con SO. Métodos: se incluyeron 15.024 participantes (9.618 SO [25,0-29,9 kg/m2], 5.406 OB [≥ 30 kg/m2]) con edades entre 18 y 59 años de la encuesta basal 2019 de la Vigilancia de Factores de Riesgo y Protección para Enfermedades Crónicas mediante una Encuesta Telefónica (VIGITEL, Brasil). Se midió el puntaje de consumo diario de alimentos mínimamente procesados y ultraprocesados y variables de confusión (edad, sexo, escolaridad, actividad física, hipertensión y diabetes). Mediante una regresión logística binaria se analizóla asociación de las puntuaciones de consumo de alimentos mínimamente procesados y ultraprocesados con la OB (odds ratio [OR]). Resultados: los cuartiles de puntuación de consumo de alimentos mínimamente procesados (1.º = 1[alimento-puntuación/día]; 2.º = 6[alimento-puntuación/día]; 3.º = 7[alimento-puntuación/día]; 4.º = 8[alimento-puntuación/día]) presentaron valores superiores en comparación con los alimentos ultraprocesados (1.º = 1[alimento-puntuación/día]; 2.º = 1[alimento-puntuación/día]; 3.º = 2[alimento-puntuación/día]; 4.º = 4[alimento-puntuación/día]). Por cada punto de alimentos mínimamente procesados consumidos, hubo una probabilidad de OB del -5,9 %. Por lo tanto, el cuartil más alto (4.º) de puntuación de consumo de alimentos mínimamente procesados representa menos probabilidades de OB (OR: -47,2 %; p < 0,001). Cada puntaje de alimentos ultraprocesados consumidos presentó probabilidades de 3.7 % de OB. Por lo tanto, un mayor consumo de alimentos ultraprocesados (cuartil 4.º) muestra mayores probabilidades de OB (OR: +14,8 %; p < 0,001). Todas las asociaciones se mantuvieron significativamente incluso después de ajustarlas por los factores de confusión. Conclusión:las puntuaciones de consumo de alimentos mínimamente procesados y ultraprocesados impactaron en la probabilidad de desarrollar OB en adultos con SB, incluso cuando se controló por factores sociodemográficos, actividad física, hipertensión y diabetes.

Otago Exercise Program Plus Cognitive Dual-task can Reduce Fall Risk, Improve Cognition and Functioning in Older Adults.

BACKGROUND: The risk of falling increases with neuromusculoskeletal and cognitive changes resulting from aging. Physical exercise shows beneficial effects on the risk of falling, but the results are unknown when associated with cognitive activity dual-task (DT). OBJECTIVE: The objective of the study was to evaluate the impacts of the Otago Exercise Program (OEP) plus DT cognitive activity on the risk of falling in older adults. METHODS: 36 older adults (83.5 ± 5.7 years) participated in a quasi-experimental study, distributed in two experimental groups and a control group: 1) OEP (OEPG; n=12), 2) OEP plus DT (OEPDTG; n = 12), and a control group (CG; n=12). Older adults were evaluated at pre- and post- 12 weeks of intervention. The thresholds for the risk of falling were considered as multiparameter scores of the 10 Meter Walking Test (10MWT), evocative 10MWT, Timed Up and Go (TUG), Sit to Stand Test (STS), and The Four-Stage Balance Test (Four-Stage), and the Montreal Cognitive Assessment (MoCA), to test the cognitive impairment. RESULTS: At baseline, all groups were homogeneous. Post-intervention, the experimental groups presented significant functional differences, in comparison to the CG, for 10MWT (OEPDTG: p= 0.002; OEPG: p= 0.002); evocative 10MWT (OEPDTG: p=0.001; OEPG: p=0.001); TUG (OEPDTG: p=0.034); STS (OEPDTG: p<0.001; OEPG: p<0.001) and cognitive for MoCA (OEPDTG: p<0.019). Significant intra-group differences (pre-post) were observed in all intervention groups, but none in CG. The risk of falling (Four-Stage) in experimental groups (OEPDTG: 33.3%; OEPG: 41.7%) was considerably lower than CG (83.3%). CONCLUSION: Otago Exercise Program alone can reduce the risk of falling due to improved functionality, but adding the dual task also improves cognitive capacity in older adults. The clinical significance of these interventions goes beyond statistics.

Handgrip strength asymmetry cut points to identify slow gait speed in six low- and middle-income countries: A cross-sectional analysis with 12,669 older adults.

BACKGROUND: Handgrip strength (HGS) asymmetry is associated with slow gait speed. Both mark muscle dysfunction, potential risk of falls, and adverse health outcomes. This association was found in older adults from high-income countries, but not yet studied in low- and middle-income countries. Moreover, there is no HGS asymmetry referential to identify the disabling process. Thus, our study aims to verify the association of HGS asymmetry with slowness in older adults from six low- and middle-income countries and to propose cut points to slowness. METHODS: A cross-sectional study with data from 12,669 older adults (≥60 years) of the Study on Global Aging and Adult Health (SAGE) conducted in six low- and middle-income countries were analyzed. Based in the difference between upper body sides HGS (asymmetry), participants were categorized in groups as 0.0-10.0% (reference group), 10.1-20.1%, 20.1-30.0% or >30.0%. Slow gait speed was established as <0.59 (men) and <0.51 (women) m/s. Associations of HGS asymmetry with gait speed were ascertained with logistic regression. HGS asymmetry index "[(HGS asymmetry*HGS)/(BMI*Age)]*100" cut points to identify slowness were generated with the ROC curve and Youden index (α = 5%). RESULTS: Compared to HGS reference group, those with HGS asymmetry of 10.1-20%, 20.1-30.0% and >30.0% had a superior odds for slowness [1.18(CI:1.02,1.42); 1.17(CI: 0.97; 1.44); and 1.21(CI:1.03;1.43), respectively]. HGS asymmetry index cut points to identify slowness were ≤1.14 (women) and ≤1.77 (men). CONCLUSIONS: HGS asymmetry association with slowness is present in economically disadvantaged countries. We proposed a new index for impaired muscle function with acceptable sensibility and specificity.

Being Physically Active Leads to Better Recovery Prognosis for People Diagnosed with COVID-19: A Cross-Sectional Study.

The regular practice of physical activity helps in the prevention and control of several non-communicable diseases. However, evidence on the role of physical activity in mitigating worsening clinical outcomes in people with COVID-19 is still unclear. The aim of this study was to verify whether different levels of physical activity provide protection for clinical outcomes caused by SARS-CoV-2 infection. A cross-sectional study was conducted with 509 adults (43.8 ± 15.71 years; 61.1% female) with a positive diagnosis of COVID-19 residing in Ribeirão Preto, São Paulo, Brazil. Participants were interviewed by telephone to determine the severity of the infection and the physical activity performed. Binary logistic regression was used to indicate the odds ratio (OR) of active people reporting less harmful clinical outcomes from COVID-19. Active people had a lower chance of hospitalization, fewer hospitalization days, less respiratory difficulty and needed less oxygen support. The results suggest that active people, compared to sedentary people, have a lower frequency of hospitalization, length of stay, breathing difficulty and need for oxygen support. These results corroborate the importance of public policies to promote the practice of physical activity, in order to mitigate the severity of the clinical outcomes of COVID-19.

Bone Mineral Content Estimation in People Living with HIV: Prediction and Validation of Sex-Specific Anthropometric Models.

People living with HIV (PWH) experience an accelerated reduction in bone mineral content (BMC), and a high risk of osteopenia and osteoporosis. Anthropometry is an accurate and low-cost method that can be used to monitor changes in body composition in PWH. To date, no studies have used anthropometry to estimate BMC in PWH. To propose and validate sex-specific anthropometric models to predict BMC in PWH. This cross-sectional study enrolled 104 PWH (64 males) aged >18 years at a local university hospital. BMC was measured using dual energy X-ray absorptiometry (DXA). Anthropometric measures were collected. We used linear regression analysis to generate the models. Cross-validations were conducted using the "leave one out", from the predicted residual error sum of squares (PRESS) method. Bland-Altman plots were used to explore distributions of errors. We proposed models with high coefficient of determination and reduced standard error of estimate for males (r2 = 0.70; SEE = 199.97 g; Q2PRESS = 0.67; SEEPRESS = 208.65 g) and females (r2 = 0.65; SEE = 220.96 g; Q2PRESS = 0.62; SEEPRESS = 221.90 g). Our anthropometric predictive models for BMC are valid, practical, and a low-cost alternative to monitoring bone health in PWH.

Association between classic and specific bioimpedance vector analysis and sarcopenia in older adults: a cross-sectional study.

BACKGROUND: To verify (1) the association between classic and specific bioelectrical impedance vector analysis (BIVA) with body composition, hydration, and physical performance in older adults with and without sarcopenia; (2) which BIVA most accurately distinguishes sarcopenia. METHODS: A sample of 94 older adults with and without sarcopenia (29 men and 65 women, 60-85 years) was evaluated. The classic and specific BIVA procedures, Dual energy X-ray absorptiometry (DXA), and deuterium dilution were performed. Sarcopenia was defined by muscle weakness and low skeletal muscle index, while severity was indicated by low physical performance. RESULTS: The BIVA's potential to monitor hydration and muscle mass loss in older adults seems feasible. Classic and specific BIVA were able to distinguish sarcopenia in women (p < 0.001), but not in men. When the sarcopenia criteria were individually analyzed, both classic and specific BIVA were able to distinguish low skeletal muscle index in women, while only classic BIVA did for men. For the criterion of slow physical performance, only the classic BIVA showed severity differences for women. The vectors of adults without sarcopenia of both sexes tended to be positioned in the left region of the ellipses, revealing a predominance of soft tissues. CONCLUSIONS: Classic BIVA has a distinct sarcopenic association with body composition, hydration, and physical performance in older adults, while specific BIVA was similar between groups. Both BIVAs are sensible to detect female morphological changes (skeletal muscle index) but not for functional (handgrip, 6-min walk test) sarcopenia criteria. These procedures are promising tools for monitoring sarcopenia risks during aging.

Foreign allometric exponents adequately normalize isokinetic knee extension strength to identify muscle weakness and mobility limitation in Portuguese older adults: a cross-sectional study.

BACKGROUND: Identifying muscle weakness is challenging, because the reduction of strength with aging does not depend only on sarcopenia, but also on sensorimotor deficits. Nevertheless, this identification is improved by adjusting muscle strength allometrically, by removing the influence of body size. However, the effectiveness of foreign models to normalize these (dys)functionalities is not yet tested. This study aimed to compare and apply foreign allometric exponents for normalizing isokinetic knee extension strength in Portuguese older adults to identify muscle weakness/mobility limitation. Additionally, to attest any populational difference, data of these people and Brazilian older adults were compared METHODS: This is a cross-sectional study encompassing 226 Portuguese (n = 132) and Brazilian (n = 94) older adults. Mobility limitation (six-minute walk test, at lowest quartile), lower limb strength (knee extension isokinetic strength at 60º/s), and body dimensions measures were taken. Foreign allometric exponents (b) were used to normalize Portuguese strength (strength/body-size variablesb). Non-normalized and normalized strength were compared (ROC) to generate the most accurate cut-point for identifying muscle weakness/mobility limitation. RESULTS: Older Portuguese men and women had better mobility than their Brazilian counterparts. Older Portuguese women had superior muscle strength to Brazilian women. Normalization from 11 foreign models removed the influence of body size on muscle strength, with a negligible correlation (r ≤ 0.30). In contrast to the non-normalized strength, the normalized strength cut-off points were sufficiently accurate (AUC ≥ 0.70) to avoid identifying false-negative cases of weakness/mobility limitation. CONCLUSIONS: Portuguese older women were stronger and had superior functional capacity compared to Brazilian ones. Normalized foreign models improved the accuracy in identifying muscle weakness/mobility limitation in Portuguese older adults. The isokinetic knee extension muscle strength normalized, even using foreign allometric exponents, should be better than no adjustment.

Sleep Quality and Quality of Life Among Older Adults During COVID-19 Pandemic: A Cross-Sectional Study.

BACKGROUND: Although home confinement reduces the number of SARS-CoV-2 infections, it may negatively impact the psychological and physical health of older adults. OBJECTIVE: The present study attempted to describe the quality of life (QoL) of older adults before and during the COVID-19 outbreak, focusing on evaluating QoL, physical activity, sitting time, and sleep quality during home confinement. METHODS: The present study was conducted in 1,063 older adults (91 % females) enrolled in a Brazilian social program. They were interviewed for QoL (EQ-5D), physical activity (international physical activity questionnaire-short), and sleep quality [Pittsburgh sleep quality index (PSQI)] after 11.6 ± 2.4 weeks of confinement. Logistic regression confirmed changes in QoL. RESULTS: The QoL (86.5 ± 14.7) decreased significantly during confinement (66.0 ± 21.0; P < 0.001), whereas the PSQI global score was 6.8 ± 3.9 points. Older adults spent 18.7 ± 29.8 min/day in moderate to vigorous physical activity, whereas they spent 325.5 ± 144.4 min/day sitting. The PSQI global score [odds ratio (OR): 1.10], sitting time (OR: 1.001), and diseases (OR: 1.23) were significantly associated with low QoL (P < 0.05). CONCLUSION: Confinement has a deleterious effect on QoL, which is influenced by quality of sleep, sitting time, and disease. Awareness regarding the significance of sleep and physical exercise in older adults can mitigate the damage to their health during confinement.

Allometrically adjusted handgrip strength and chair stand test cut points to identify sarcopenia in older Portuguese adults / Pontos de corte da força de preensão manual e teste de sentar e levantar da cadeira ajustados alometricamente para identificar sarcopenia em idosos portugueses

ABSTRACT Absolute muscle strength or adjusted by body mass index (BMI) are useful to identify sarcopenia. However, these values are not accurate for older adults with extreme body sizes because the nonlinear relationship between strength and body size. The purpose was to determine cut-off points for identify sarcopenia in older adults using allometric coefficients to normalise handgrip strength (HGS) and 30-sec chair stand test (30-s CST) by body size. Allometric exponents were proposed with log-linear models for body-size variables (body mass, height and BMI). The remotion of body-size effect on muscle strength with allometric normalisation was tested by partial correlation. Cut-off points for low muscle strength were established by ROC curve and Youden index considering functional limitation (six-minute walk test<400m). Allometric exponents provided for body-size variables range from -0.01 to 2.28 (HGS) and -0.27 to 0.21 (30-s CST). The effect of body size on muscle strength was removed with allometric normalisation (r<0.30). Cut-off points accuracy was always adequate (AUC≥0.78; p<0.001). In conclusion, cut-off points of HGS and 30-s CST allometrically normalised were proposed to identify sarcopenia in Portuguese older adults and allometry maintained adequate the accuracy (AUC>70%). Allometry removed influence of body size on the expression of HGS and 30-s CST and permits evaluate muscle strength regardless of body-size.

RESUMO A força muscular absoluta ou ajustada pelo índice de massa corporal (IMC) é útil para identificar a sarcopenia. No entanto, esses valores não são precisos para idosos com tamanhos corporais extremos devido à relação não linear entre força e tamanho corporal. O objetivo foi determinar os pontos de corte para identificar a sarcopenia em idosos usando coeficientes alométricos para normalizar a força de preensão manual (FPM) e teste de sentar e levantar da cadeira em 30 segundos (30-s CST) por tamanho corporal. Os expoentes alométricos foram propostos com modelos log-lineares para variáveis de tamanho corporal (massa corporal, estatura e IMC). A remoção do efeito do tamanho corporal na força muscular com normalização alométrica foi testada por correlação parcial. Os pontos de corte para baixa força muscular foram estabelecidos pela curva ROC e índice de Youden considerando a limitação funcional (teste de caminhada de seis minutos<400m). Os expoentes alométricos fornecidos para variáveis de tamanho corporal variam de -0,01 a 2,28 (FPM) e -0,27 a 0,21 (30-s CST). O efeito do tamanho corporal na força muscular foi removido com normalização alométrica (r<0,30). A precisão dos pontos de corte sempre foi adequada (AUC≥0,78; p<0,001). Em conclusão, foram propostos pontos de corte para FPM e 30-s CST normalizados alometricamente para identificar sarcopenia em idosos portugueses e a alometria manteve a precisão adequada (AUC>70%). A alometria removeu a influência do tamanho corporal na expressão da FPM e 30-s CST e permite avaliar a força muscular independentemente do tamanho corporal.

Cross-validation of 20 anthropometric prediction equations for appendicular muscle mass in older Brazilian women: a cross-sectional study / Validação cruzada de 20 equações antropométricas de massa muscular apendicular para idosas brasileiras: um estudo transversal

Objective: To test the cross-validation of anthropometric prediction equations for appendicular muscle mass (AMM) in older Brazilian women. Methods: Sixty-seven older women (69.84 ± 5.95 years old) underwent anthropometric measurements. AMM (kg) reference values obtained by dual-energy X-ray absorptiometry (AMMDXA) were compared to 20 anthropometric equations for estimating AMM in older adults. A paired t-test (p > 0.05), standard error of estimate (SEE < 3.50 kg), and r2 > 0.70 confirmed the validity of the equations. The agreement between predictions and the reference was also verified (Bland-Altman analysis of agreement between methods). Results: Four American equations and one Mexican equation were not statistically different from AMMDXA (p > 0.05) but did not present suitable r2 values for validation. The American equation from the National Health and Nutrition Examination Survey (NHANES), AMM (kg) = (-0.04 × age [years]) + (0.46 × calf circumference [cm]) + (0.32 × arm circumference [cm]) + (0.11 × thigh circumference [cm]) ­ (0.27 × body mass index [BMI, kg/m2 ]) + (0.07 × waist circumference [cm]) ­ 13 119 showed the best performance (r2 = 0.64; SEE = 3.24 kg), with minimal mean difference (0.26 kg), no heteroscedasticity for extreme values, and with high agreement with the Brazilian sample (-3.90 to 3.40 kg). Conclusion: When specific equations for a given population are not available, the use of generic equations of greater sample representativeness with scientifically and reliably analyzed data is allowed.

Objetivo: Testar a validação cruzada das equações antropométricas preditivas da massa muscular apendicular (MMA) em idosas brasileiras. Metodologia: Sessenta e sete idosas (69,84 ± 5,95 anos) foram submetidas a medidas antropométricas. Os valores de referência da MMA (kg) fornecida pela absorciometria de raios X de dupla energia (MMADXA) foi comparada com 20 equações antropométricas preditivas para estimar a MMA para idosos. Teste t pareado (p > 0,05), erro padrão de estimativa (EPE) < 3,50 kg e r2 > 0,70 confirmaram a validade das equações. A concordância entre as previsões e a referência também foi verificada (análise de concordância entre métodos de Bland-Altman). Resultados: Quatro equações americanas e uma equação mexicana não foram estatisticamente diferentes da MMADXA (p > 0,05), mas nenhuma delas apresentou r2 adequado para validação. A equação americana dos dados do National Health and Nutrition Examination Survey (NHANES), MMA (kg) = (-0,04 × idade [anos]) + (0,46 × circunferência da panturrilha [cm]) + (0,32 × circunferência do braço [cm]) + (0,11 × circunferência da coxa [cm]) ­ (0,27 × índice de massa corporal-IMC [kg/m2 ]) + (0,07 × circunferência da cintura [cm]) ­ 13,12 apresentou o melhor desempenho (r2 = 0,64; EPE = 3,24 kg): com diferença média mínima (0,26 kg), sem heterocedasticidade para valores extremos e alta concordância com a amostra brasileira (-3,90 a 3,40 kg). Conclusão: Quando não existem equações específicas para uma determinada população, é permitida a utilização de equações genéricas de maior representatividade amostral, cujos dados tenham sido analisados de forma científica e confiável

Identification of muscle weakness in older adults from normalized upper and lower limbs strength: a cross-sectional study.

BACKGROUND: To propose cut-off points for older adults' weakness for upper and lower limbs muscle strength normalized by body size with the ratio standard/muscle quality and allometric scaling. METHODS: Ninety-four community-dwelling older adults (69.1% women) were assessed for 49 body-size variables (anthropometry, body composition and body indexes), handgrip strength (HGS), one maximum repetition measurement for knee extensors (1RM), isokinetic knee extension peak torque at 60°/s (PT), and six-minute walk test (6MWT). Ratio standard or muscle quality (muscle strength/body size) and allometric scaling (muscle strength/body sizeb; when b is the allometric exponent) were applied for body-size variables significantly correlated with HGS, 1RM and PT. Cut-off points were computed according to sex based on mobility limitation (6MWT < 400 m) with ROC curve and Youden index. RESULTS: Absolute HGS, 1RM and PT cut-off points were not adequate because they were associated with body size (r > 0.30). But it was corrected with muscle strength normalization according to body size-variables: HGS (n = 1); 1RM (n = 24) and PT (n = 24). The best cut-off points, with the highest area under the curve (AUC), were found after normalization for men: HGS/forearm circumference (1.33 kg/cm, AUC = 0.74), 1RM/triceps skinfold (4.22 kg/mm, AUC = 0.81), and PT/body mass*height0.43 (13.0 Nm/kg*m0.43, AUC = 0.94); and for women: HGS/forearm circumference (1.04 kg/cm, AUC = 0.70), 1RM/body mass (0.54 kg/kg, AUC = 0.76); and PT/body mass0.72 (3.14 Nm/kg0.72; AUC = 0.82). CONCLUSIONS: Upper and lower limbs muscle weakness cut-off points standardized according to body size were proposed for older adults of both sexes. Normalization removes the effect of extreme body size on muscle strength (both sexes) and improves the accuracy to identify weakness at population level (for women, but not in men), reducing the risk of false-negative/positive cases.

The Associations of Objectively Measured Physical Activity, Fundamental Motor Skills and Time in Sedentary Behavior in Children: A Cross-Sectional Study.

Reduced levels of children's physical activity (PA) and fundamental motor skills (FMS) along with increased sedentary behaviors have been observed in recent years. Yet, associations between these variables are not yet well established. This study aimed to observe the associations between FMS, PA and sedentary time in elementary school children. We evaluated 148 children (70 boys; Mage = 8.7, SD = 1.4 years old) from a private school using the Test of Gross Motor Development - Second Edition (TGMD-2) to measure FMS and examine locomotor, object control, and gross motor skills. We used accelerometry to measure PA performed on weekdays, weekends and total PA. We used descriptive statistics, partial correlations controlling for sex and age, and linear regression adjusted for sex and equivalent motor age to explain the relationships. Total moderate to vigorous PA (MVPA) (ß: 0.153; p = .009) and weekend MVPA (ß: 0.171; p = .003) were significantly associated with FMS, regardless of gender and equivalent motor age. Sedentary time was not significantly associated with FMS (p = .065). Girls and boys who met PA recommendations (≥60 minutes/day of moderate to vigorous PA) had higher frequencies of high ratings on the TGMD-2 (p < .001 e p = .001, respectively). MVPA was associated with children's FMS development, possibly affecting the quality of movement performed in children's daily lives.

Normalizing calf circumference to identify low skeletal muscle mass in older women: a cross-sectional study / Normalización de la circunferencia de la pantorrilla para identificar la masa muscular esquelética baja en las mujeres mayores: un estudio transversal

Introduction: functional limitation is a result of sarcopenia and is associated with loss of skeletal muscle mass (SMM). Cost-effective methods are important for the identification of sarcopenia. Objective: to propose cutoff points for normalized calf circumference (CC) in order to identify low SMM in older women based on their functional limitation.Methods: in this descriptive, cross-sectional study the CC values of a young female sample (n = 78) were used to establish cutoff points (-2 SD) for low SMM in older women (n = 67). Functional limitation was identified by the six-minute walk test (≤ 400 m). CC was normalized by body mass, height, and BMI. The diagnostic accuracy of CC was calculated with a ROC curve, using functional limitation as standard. Results: cutoff points and area under the curve (AUC) were: CC (≤ 28.5; 0.62); CC·body mass-1 (≤ 0.40; 0.63); CC·height-2 (≤ 8.52; 0.55) and CC·BMI-1 (≤ 1.10; 0.73). Only CC·BMI-1 achieved a desirable accuracy (AUC > 0.7) to distinguish functional limitation. Conclusion: the accuracy attained supports the use of CC·BMI-1 to identify low SMM in older women. In the clinical context it is possible to predict the risk of sarcopenia when sophisticated methods for determining SMM are not available. (AU)

Introducción: la limitación funcional es consecuencia de la sarcopenia y se asocia con la pérdida de masa muscular esquelética (MME). Los métodos rentables son importantes para la identificación de la sarcopenia. Objetivo: proponer puntos de corte para la circunferencia de la pantorrilla (CP), normalizada para identificar un MME bajo en mujeres mayores en función de su limitación funcional. Métodos: en este estudio descriptivo de carácter transversal se utilizaron los valores de CP de una muestra de mujeres jóvenes (n = 78) para establecer los puntos de corte (-2 DS) de la MME baja en las mujeres mayores (n = 67). La limitación funcional se identificó mediante la prueba de la marcha de seis minutos (≤ 400 m). La CP se normalizó por la masa corporal, la altura y el IMC. La precisión diagnóstica de la CP se calculó con la curva ROC, utilizando como estándar la limitación funcional. Resultados: los puntos de corte y el área bajo la curva (AUC) fueron: CP (≤ 28,5; 0,62); CP·masa corporal-1 (≤ 0,40; 0,63); CP·altura-2 (≤ 8,52; 0,55) y CP·IMC-1 (≤ 1,10; 0,73). Solo el CP·IMC-1 logró la precisión deseable (AUC > 0,7) para distinguir la limitación funcional. Conclusión: la precisión alcanzada respalda el uso de CP·IMC-1 para identificar la MME baja en las mujeres mayores. En el contexto clínico es posible predecir el riesgo de sarcopenia cuando no se dispone de métodos sofisticados para determinar la MME. (AU)

Normalizing calf circumference to identify low skeletal muscle mass in older women: a cross-sectional study.

INTRODUCTION: Introduction: functional limitation is a result of sarcopenia and is associated with loss of skeletal muscle mass (SMM). Cost-effective methods are important for the identification of sarcopenia. Objective: to propose cutoff points for normalized calf circumference (CC) in order to identify low SMM in older women based on their functional limitation. Methods: in this descriptive, cross-sectional study the CC values of a young female sample (n = 78) were used to establish cutoff points (-2 SD) for low SMM in older women (n = 67). Functional limitation was identified by the six-minute walk test (≤ 400 m). CC was normalized by body mass, height, and BMI. The diagnostic accuracy of CC was calculated with a ROC curve, using functional limitation as standard. Results: cutoff points and area under the curve (AUC) were: CC (≤ 28.5; 0.62); CC·body mass-1 (≤ 0.40; 0.63); CC·height-2 (≤ 8.52; 0.55) and CC·BMI-1 (≤ 1.10; 0.73). Only CC·BMI-1 achieved a desirable accuracy (AUC > 0.7) to distinguish functional limitation. Conclusion: the accuracy attained supports the use of CC·BMI-1 to identify low SMM in older women. In the clinical context it is possible to predict the risk of sarcopenia when sophisticated methods for determining SMM are not available.

INTRODUCCIÓN: Introducción: la limitación funcional es consecuencia de la sarcopenia y se asocia con la pérdida de masa muscular esquelética (MME). Los métodos rentables son importantes para la identificación de la sarcopenia. Objetivo: proponer puntos de corte para la circunferencia de la pantorrilla (CP), normalizada para identificar un MME bajo en mujeres mayores en función de su limitación funcional. Métodos: en este estudio descriptivo de carácter transversal se utilizaron los valores de CP de una muestra de mujeres jóvenes (n = 78) para establecer los puntos de corte (-2 DS) de la MME baja en las mujeres mayores (n = 67). La limitación funcional se identificó mediante la prueba de la marcha de seis minutos (≤ 400 m). La CP se normalizó por la masa corporal, la altura y el IMC. La precisión diagnóstica de la CP se calculó con la curva ROC, utilizando como estándar la limitación funcional. Resultados: los puntos de corte y el área bajo la curva (AUC) fueron: CP (≤ 28,5; 0,62); CP·masa corporal-1 (≤ 0,40; 0,63); CP·altura-2 (≤ 8,52; 0,55) y CP·IMC-1 (≤ 1,10; 0,73). Solo el CP·IMC-1 logró la precisión deseable (AUC > 0,7) para distinguir la limitación funcional. Conclusión: la precisión alcanzada respalda el uso de CP·IMC-1 para identificar la MME baja en las mujeres mayores. En el contexto clínico es posible predecir el riesgo de sarcopenia cuando no se dispone de métodos sofisticados para determinar la MME.