Avaliação do consumo alimentar, composição corporal, espessura muscular e desempenho físico em mulheres de meia idade e idosas

Abstract

Introduction: Aging leads to loss of muscle mass and decreased strength, altering the thickness of the muscle in an evident way, especially in women, with a consequent increase in the risk of health adversities and a decline in physical and functional capacities. Objectives: a) to compare food consumption, muscle thickness, body composition and physical performance in middle-aged and elderly women; b) to analyze the association between age, muscle thickness, body composition and protein consumption in these women, and; c) to propose a model that estimates effort tolerance based on explanatory variables in middle-aged and elderly women. Methods: The sample consisted of 107 middle-aged and elderly women with a mean age of 60 ± 9.0 years and a BMI of 29 ± 4.0kg/m2. Food consumption was assessed using the QFA-Nova, biceps brachii muscle thickness (BBMT) and rectus femoris muscle thickness (RFMT) using ultrasound, body composition using DXA and Bioimpedance and physical performance using the 6MWT, handgrip strength and the 30s stand and sit test. The data obtained between the groups was compared using the independent t-test, Mann-Whitney U-test or Fisher's exact test. The correlation between age, body composition, muscle thickness and physical performance was assessed using the Pearson or Spearman correlation test, depending on the normality of the data. The association between the explanatory variables and the dependent variable (effort tolerance) was verified using the multiple linear regression test. These analyses were carried out using SPSS software version 23.0 and the significance level accepted was p<0.05. Results: Middle-aged women had higher AMMI (Appendicular muscle mass index), lean mass, energy value and HS (Handgrip Strength). Elderly women had higher intakes of protein, saturated fat, lower limb strength and endurance. There was a moderate association between age and TMM (Total Muscle Mass) (p=0.001), AMMI (p=0.002), lean mass (p<0.000) and a weak one for RFMT (p=0.044). BMI showed a strong association with TMM, AMMI, fat mass and fat percentage, and a moderate association with lean mass, RFMT and BBMT (p<0.000 in all analyses). There was also a strong association between TMM and AMMI, fat mass and lean mass; a moderate association with fat percentage and muscle thickness (p<0.000 for all analyses) and a weak association with HS (p=0.002). Fat mass showed a strong association with fat percentage, a moderate association with lean mass and BBMT (p<0.000 for these analyses) and a weak association with RFMT (p=0.002). Fat percentage showed a weak association with BBMT (p=0.008), with 6MWT (p=0.013), and lean mass showed a weak association with RFMT (p=0.003) and a moderate association with BBMT and HS (p<0.000 for both analyses). There was a strong association between RFMT and BBMT and between 30s Stand and sit test and 6MWT (p<0.000 for both analyses). In the regression analysis, the model with the explanatory variables’ handgrip strength, lower limb strength and endurance and BMI predicted 41.481 of the variances of this dependent variable (tolerance to physical effort = 41.481 + 0.509 (lower limb strength and endurance) + 0.205 (handgrip strength) - 0.156 (BMI)). Conclusion: The aging process in women shows a greater loss of muscle mass in the elderly, however these women had a higher protein intake, were more physically active, which may have favored an improvement in the strength and endurance of the lower limbs, and together with HS and BMI make up the model that best explains effort tolerance.