Ricardo Moreno Lima

Fat-Free Mass, Strength, and Sarcopenia are Related to Bone Mineral Density in Older Women

This study examined the association between fat-free mass (FFM) and muscle strength with bone mineral density (BMD), and compared the BMD values between sarcopenic and nonsarcopenic older women. After the exclusion criteria were applied, a total of 246 volunteers (age: 66.51+/-6.37 yr) participated in the analysis. Subjects underwent FFM and BMD evaluation by dual-energy X-ray absorptiometry and quadriceps strength by an isokinetic dynamometer. To address the potential for confounding by height, FFM values were considered relative to body height squared. For fat mass correction, fat-adjusted FFM was calculated. Individuals were classified as sarcopenic if their appendicular FFM was less than 5.45 kg/m2. All the evaluated FFM indexes were significantly correlated with the measured BMD sites. Sarcopenic individuals presented significantly lower whole body and trochanter BMD, and were significantly more prone to have low BMD. Muscle strength was also correlated with BMD sites; however, when it was expressed relative to body weight, the significance disappeared. Nevertheless, volunteers with low relative strength had higher risk of having low trochanter BMD. It can be concluded, in older women, that FFM is significantly correlated with BMD independently of height and fat mass. Muscle strength was also correlated with BMD, although the correlation was weaker when corrected for body weight. Finally, sarcopenic elderly women were more likely to have low BMD and muscle strength.

Redução da pressão arterial e do duplo produto de repouso após treinamento resistido em idosas hipertensas

BACKGROUND: Due to the existing controversies in literature about the potential benefits of resistance exercise training (RT) on arterial blood pressure (BP) at rest, and the lack of studies conducted with elderly hypertensive individuals, RT is seldom recommended as a non-pharmacological treatment for arterial hypertension. OBJECTIVE: To verify the effect of progressive RT on BP, HR, and RPP in elderly women with controlled hypertension. METHODS: 20 elderly women (66.8 ± 5.6 years of age), with a sedentary lifestyle, monitored with anti-hypertensive medication, participated in a 12-week RT program (resistance training group - RTG). Twenty-six elderly women (65.3 ± 3.4 years of age) with controlled hypertension did not engage in physical exercise during the study period, and composed the control group. RESULTS: After RT, there was a significant reduction in SBP, MBP, and DP values at rest. No significant drops in DBP and HR values at rest were observed after RT in both groups. The reduction in the RTG was 10.5 mmHg, 6.2 mmHg, and 2218.6 mmHg x bpm for SBP, MBP, and RPP, respectively. CONCLUSION: Progressive RT reduced SBP, MBP, and RPP values at rest of hypertensive elderly women who were on anti-hypertensive treatment.

Predicting insulin resistance in children: anthropometric and metabolic indicators

OBJECTIVE To predict insulin resistance in children based on anthropometric and metabolic indicators by analyzing the sensitivity and specificity of different cutoff points. METHODS A cross-sectional study was carried out of 109 children aged 7 to 11 years, 55 of whom were obese, 23 overweight and 31 well-nourished, classified by body mass index (BMI) for age. Measurements were taken to determine BMI, waist and hips circumferences, waist circumference/hip circumference ratio, conicity index and body fat percentage (dual emission X-ray absorptiometry). Fasting blood samples were taken to measure triglyceridemia, glycemia and insulinemia. Insulin resistance was evaluated by the glycemic homeostasis method, taking the 90th percentile as the cutoff point. Receiver operating characteristic curves were analyzed to a 95% confidence interval in order to identify predictors of glycemic homeostasis, and sensitivity and specificity were then calculated. RESULTS After analysis of the area under the receiver operating characteristic curve (confidence interval), indicators that demonstrated the power to predict insulin resistance were, in the following order: insulinemia = 0.99 (0.99-1.00), 18.7 microU mL(-1); body fat percentage = 0.88 (0.81-0.95), 41.3%; BMI = 0.90 (0.83-0.97), 23.69 kg m(2-(1)); waist circumference= 0.88 (0.79-0.96), 78.0 cm; glycemia = 0.71 (0.54-0.88), 88.0 mg dL(-1); triglyceridemia = 0.78 (0.66-0.90), 116.0 mg dL(-1) and conicity index = 0.69 (0.50-0.87), 1.23 for the whole sample; and were: insulinemia = 0.99 (0.98-1.00), 19.54 microU mL(-1); body fat percentage = 0.76 (0.64-0.89), 42.2%; BMI = 0.78 (0.64-0.92), 24.53 kg m(2-(1)); waist circumference = 0.77 (0.61-0.92), 79.0 cm and triglyceridemia = 0.72 (0.56-0.87), 127.0 mg dL(-1), for the obese subgroup. CONCLUSIONS Anthropometric and metabolic indicators appear to offer good predictive power for insulin resistance in children between 7 and 11 years old, employing the cutoff points with the best balance between sensitivity and specificity of the predictive technique.

Association between sarcopenia, sarcopenic obesity, muscle strength and quality of life variables in elderly women.

OBJECTIVE To investigate the association between sarcopenia, sarcopenic obesity and muscle strength and variables related to quality of life in elderly women. METHOD The sample consisted of 56 female volunteers who underwent body composition analysis (BMI and x-ray absorptiometry dual-energy DXA). Handgrip strength was measured using a Jamar dynamometer. We used the SF-36 health questionnaire to analyze quality of life. The data were analyzed with descriptive statistics and the Pearson correlation coefficient; SPSS 15.0 was used to perform the statistical analysis. RESULTS The mean age of the subjects was 64.92±5.74 years; of the 56 volunteers evaluated, 19.64% (n=11) were classified as sarcopenic obese and 45 (80.36%) were not. Thirteen volunteers (23.21%) were classified as sarcopenic while 43 (76.78%) were not. Although there were no statistically significant differences between the studied parameters and quality of life among those with sarcopenia or sarcopenic obesity, the values were lower in affected individuals. Interestingly, handgrip strength correlated positively and significantly with all of the SF-36 dimensions except VIT (p=0.08) and SM (p=0.25). CONCLUSIONS Seeing that handgrip strength is a determining factor in quality of life aspects in this population, the screening and identification of small functional changes using simple clinical measures may facilitate early intervention and help prevent disability. In contrast, neither sarcopenia nor sarcopenic obesity were found to be associated with quality of life.

Identification of sarcopenic obesity in postmenopausal women: a cutoff proposal.

Sarcopenic obesity is the combination of reduced fat-free mass (FFM) and increased fat mass (FM) with advancing age but there is lack of clear criteria for its identification. The purposes of the present investigation were: 1) to determine the prevalence of postmenopausal women with reduced FFM relative to their FM and height, and 2) to examine whether there are associations between the proposed classification and health-related variables. A total of 607 women were included in this cross-sectional study and were separated into two subsets: 258 older women with a mean age of 66.8 ± 5.6 years and 349 young women aged 18-40 years (mean age, 29.0 ± 7.5 years). All volunteers underwent body composition assessment by dual-energy X-ray absorptiometry. The FFM index relative to FM and height was calculated and the cutoff value corresponded to two standard deviations below the mean of the young reference group. To examine the clinical significance of the classification, all older participants underwent measurements of quadriceps strength and cardiorespiratory fitness. Values were compared between those who were classified as low FFM or not, using an independent samples t-test and correlations were examined. The cutoff corresponded to a residual of -3.4 and generated a sarcopenic obesity prevalence of 19.8% that was associated with reduced muscle strength and aerobic fitness among the older participants. Also, the index correlated significantly with the health-related fitness variables. The results demonstrated reduced functional capacity for those below the proposed cutoff and suggested applicability of the approach as a definition for sarcopenic obesity.

ACE and ACTN3 Genotypes in Older Women: Muscular Phenotypes

This study examined the association between ACE I/D and ACTN3 R577X polymorphisms and muscle-related phenotypes and their adaptation to resistance training in older women. Volunteers (n=246;age=66.7 ± 5.5 years) underwent quadriceps strength assessment using isokinetics and fat-free mass by dual energy X-ray absorptiometry. 79 volunteers performed 24 weeks of resistance training and 75 were studied as controls. Genotypes were identified by standard procedures. No associations were observed for muscle strength for either gene, but volunteers carrying the D/D genotype presented higher appendicular fat-free mass compared to the I-allele carriers (6.3 ± 0.1 vs. 6.1 ± 0.1 kg/m (2)). The X-allele carriers presented higher relative fat-free mass when compared to homozygous R/R (16.3 ± 0.1 vs. 15.9 ± 0.1 kg/m (2)). All fat-free mass variables were significantly greater for carriers of both X/X and D/D genotypes. In response to RT, only the I-allele carriers significantly increased fat-free mass and a significant training × genotype interaction was noted. These findings do not support a pivotal role for the studied polymorphisms in determining muscle strength in older women, but suggest a modest role in fat-free mass determination. Of note, the results provide a novel insight that these genetic variations may interact to determine muscle mass in older women.

EFFECTS OF 24 WEEKS OF PROGRESSIVE RESISTANCE TRAINING ON KNEE EXTENSORS PEAK TORQUE AND FAT-FREE MASS IN OLDER WOMEN

Rabelo, HT, Bezerra, LA, Terra, DF, Lima, RM, Silva, MAF, Leite, TK, and de Oliveira, RJ. Effects of 24 weeks of progressive resistance training on knee extensors peak torque and fat-free mass in older women. J Strength Cond Res 25(8): 2298-2303, 2011—This study examined the effects of resistance training (RT) on knee extensor peak torque (KEPT) and fat-free mass (FFM) in older women. Seventy-eight volunteers (67.1 ± 5.9 years old) underwent 24 weeks of progressive RT (RTG) while 76 (67.4 ± 5.9 years old) were studied as controls (CG). Dominant knee extension peak torque was assessed using an isokinetic dynamometer (Biodex System 3) and FFM measurements were performed by dual-energy x-ray absorptiometry. Muscle strength and FFM were evaluated before and after the intervention in all volunteers. Participants in the RTG trained major muscle groups 3 times per week during 24 weeks. Training load was kept at 60% of 1 repetition maximum in the first 4 weeks, 70% in the following 4 weeks, and 80% in the remaining 16 weeks, with repetitions, respectively, decreasing from 12, 10, and 8. A Split-plot analysis of variance was performed to examine between- and within-group differences, and the level of significance was accepted at p ≤ 0.05. It was observed that the RTG showed significant increases in KEPT (from 89.9 ± 21.8 to 102.8 ± 22.6 N·m; p < 0.05) and FFM (from 36.4 ± 4.0 to 37.1 ± 4.2 kg, p < 0.05). Appendicular FFM was also significantly increased after the intervention period in the RTG (13.9 ± 1.8 to 14.2 ± 1.9 kg, p < 0.05). None of these changes were observed for the CG. Consistent with the literature, it is concluded that a progressive RT program promotes not only increases in muscle strength, as evaluated by an isokinetic dynamometer, but also in FFM as evaluated by the DXA, in elderly women.

Predição da resistência à insulina em crianças: indicadores antropométricos e metabólicos

OBJECTIVE: To predict insulin resistance in children based on anthropometric and metabolic indicators by analyzing the sensitivity and specificity of different cutoff points. METHODS: A cross-sectional study was carried out of 109 children aged 7 to 11 years, 55 of whom were obese, 23 overweight and 31 well-nourished, classified by body mass index (BMI) for age. Measurements were taken to determine BMI, waist and hips circumferences, waist circumference/hip circumference ratio, conicity index and body fat percentage (dual emission X-ray absorptiometry). Fasting blood samples were taken to measure triglyceridemia, glycemia and insulinemia. Insulin resistance was evaluated by the glycemic homeostasis method, taking the 90th percentile as the cutoff point. Receiver operating characteristic curves were analyzed to a 95% confidence interval in order to identify predictors of glycemic homeostasis, and sensitivity and specificity were then calculated. RESULTS: After analysis of the area under the receiver operating characteristic curve (confidence interval), indicators that demonstrated the power to predict insulin resistance were, in the following order: insulinemia = 0.99 (0.99-1.00), 18.7 µU×mL-1; body fat percentage = 0.88 (0.81-0.95), 41.3%; BMI = 0.90 (0.83-0.97), 23.69 kg×m2-¹; waist circumference= 0.88 (0.79-0.96), 78.0 cm; glycemia = 0.71 (0.54-0.88), 88.0 mg×dL-1; triglyceridemia = 0.78 (0.66-0.90), 116.0 mg×dL-1 and conicity index = 0.69 (0.50-0.87), 1.23 for the whole sample; and were: insulinemia = 0.99 (0.98-1.00), 19.54 µU×mL-1; body fat percentage = 0.76 (0.64-0.89), 42.2%; BMI = 0.78 (0.64-0.92), 24.53 kg×m2-¹; waist circumference = 0.77 (0.61-0.92), 79.0 cm and triglyceridemia = 0.72 (0.56-0.87), 127.0 mg×dL-1, for the obese subgroup. CONCLUSIONS: Anthropometric and metabolic indicators appear to offer good predictive power for insulin resistance in children between 7 and 11 years old, employing the cutoff points with the best balance between sensitivity and specificity of the predictive technique.

Sarcopenia and sarcopenic obesity classifications and cardiometabolic risks in older women

The purpose of this study was to examine the association between sarcopenia and sarcopenic obesity (SO) with cardiometabolic risk factors in postmenopausal women. 149 volunteers (67.17±6.12 years) underwent body composition assessment using dual energy X-ray absorptiometry (DXA) and had analyzed blood samples collected for lipid profile, glucose metabolism and C-reactive protein (CRP). Sarcopenia was defined as an appendicular fat-free mass (AFFM) divided by height squared ≤5.45 kg/m(2) while SO was classified based on the residuals of a regression. Waist circumference (WC) and arterial blood pressure were also measured. Students t-tests and correlations were used for analyses. Prevalence of sarcopenia and SO were respectively 16.8 and 21.5%. WC was significantly correlated with all the examined risk factors. AFFM relative to height squared was positively correlated with systolic blood pressure (SBP) and diastolic blood pressure (DBP), CRP, insulinaemia, HOMA score, and those classified as sarcopenic presented lower HOMA score when compared to nonsarcopenic. Regarding SO, although volunteers classified presented significantly higher fat mass (FM) and lower AFFM, it was not observed association with the examined risk factors. These findings support the association between WC and cardiometabolic risk factors in older women. In contrast, the approaches used to define sarcopenia and SO are not associated with cardiometabolic impairments.

resistance training improves isokinetic strength and metabolic syndrome-related phenotypes in postmenopausal women

Purpose To examine the effects of resistance training (RT) on metabolic syndrome-related phenotypes in postmenopausal women. Patients and methods Twenty-two postmenopausal women (65.0±4.2 years) underwent 12 weeks of whole body progressive training with intensity prescribed based on rating of perceived exertion. Dominant knee extension strength was assessed using an isokinetic dynamometer before and after the intervention. Moreover, all volunteers had blood samples collected for lipid profile, glycemic control, and C-reactive protein analyses. Waist circumference and arterial blood pressure were also measured at baseline and after the training period. Student’s t-tests for paired samples and repeated measures ANOVA were used to compare dependent variables, and statistical significance was set at P<0.05. Results Isokinetic muscle strength significantly increased (P<0.01) with training. It was observed that waist circumference as well as total and low-density lipoprotein cholesterol levels significantly decreased with training (P<0.01). Total cholesterol/high-density lipoprotein cholesterol ratio, an important marker of cardiovascular disease incidence, was also significantly reduced (from 3.91±0.91 to 3.60±0.74; P<0.01) after the program. Blood glucose, basal insulin, and homeostatic model assessment of insulin resistance were also significantly reduced (P<0.01). No significant alterations were observed for resting blood pressure, triglycerides, or C-reactive protein. Conclusion Based on the observed results, it can be concluded that a 12-week progressive RT program, besides increasing isokinetic muscle strength, induces beneficial alterations on metabolic syndrome-related phenotypes in postmenopausal women. These findings highlight this mode of exercise as an important component of public health promotion programs for aged women. RT improves isokinetic strength and metabolic syndrome-related phenotypes in postmenopausal women.