RESUMO
BACKGROUND: In Anorexia Nervosa (AN) recovery, body mass index (BMI) may not reflect body composition. To investigate recovery, bioelectrical impedance (BIA) parameters and energy expenditure were investigated in patients with active and recovering AN, with emphasis on phase angle (PA), a BIA parameter. METHODS: BMI, PA, indirect BIA parameters (fat free mass, fat mass, total body water, fat free mass index, fat mass index) and resting metabolic rate (RMR) were obtained. Data from subjects distributed to active AN (ANact, n = 9), recovered AN (ANrec, n = 9) and healthy individuals (HI) (n = 16) were compared employing univariate methods and ordinal logistic regression. RESULTS: In univariate comparison, the BMI would not distinguish recovered individuals; this distinction was observed for the PA (p = < 0,001). PA showed a good capacity to discriminate, between ANrec and HI (AUC = 0.792; CI = 0.564- 1.000; p = 0.017). In 2 models of ordinal logistic regression PA (OR = 0.123; 95% CI 0.030; 0.503 and OR = 0.091; 95% CI 0.016; 0.528) remained as a significant independent variable, indicating that increases in PA are related to higher probabilities of moving from ANact, to ANrec and to HI group. Bivariate regression indicated the presence of a relationship between PA and (R2 = 0.266, p = 0.002). CONCLUSIONS: Changes in body composition and energy expenditure were observed in recovered anorexics with normal BMI. PA can play an important role in the assessment of recovering anorexic patients.
In recovery from anorexia nervosa, the body mass index does not reflect changes in body composition. Energy expenditure can change according to body composition in an anorexia nervosa and normal individuals. To investigate distinctive parameters in recovering Anorexia Nervosa patients, we evaluated body mass index and other indices obtained from body measurements by bioimpedance among patients with anorexia nervosa with low weight and in the weight recovery phase compared with a group of normal weight women without anorexia nervosa. In conclusion, we observed that one of these indexes, the phase angle can play an important role in the assessment of nutritional status in recovering anorexia nervosa.
RESUMO
A taxa metabólica de repouso (TMR) pode ser determinada por calorimetria indireta (CI). Porém, em função da praticidade, na prática clínica na maioria das vezes esta é estimada por equações de predição, as quais foram desenvolvidas em estudos envolvendo indivíduos não atletas. Apesar de alguns autores terem indicado que tais equações não estimam adequadamente a TMR, estas têm sido bastante utilizadas para calculá-la e prescrever dietas, inclusive para atletas. O objetivo deste estudo foi comparar a TMR determinada por CI com a estimada pelas equações de Harris & Benedict (HB), Schofield, FAO/WHO/UNU e Henry & Rees (HR), em 15 homens ciclistas, de 24,4 ± 3,68 anos, apresentando índice de massa corporal de 21,97 ± 1,46kg/m² e VO2máx de 70,00 ± 5,32mL(kg.min)-1. Para comparar a TMR determinada por CI e pelas equações, utilizou-se o tratamento estatístico testes t de Student (variáveis com distribuição normal) e de Mann-Whitney (variáveis sem distribuição normal), considerando p < 0,05. Além disso, foi realizada correlação de Pearson entre TMR e massa livre de gordura (MLG). Verificou-se que a TMR foi subestimada em 23,5 por cento, 16,7 por cento, 16,8 por cento e 16,9 por cento, respectivamente, quando se utilizaram as equações de HR, FAO/WHO/UNU, Schofield e HB, em relação à TMR obtida por CI. A TMR se correlacionou com a MLG (r = 0,551, p = 0,03). Os resultados confirmam que as equações avaliadas não são adequadas para estimar a TMR em atletas. Tais resultados podem ser explicados pela maior quantidade de MLG apresentada por atletas e possivelmente maior resposta dos receptores β-adrenérgicos aos estímulos do sistema nervoso simpático, resultando em TMR mais alta que em indivíduos sedentários. Diante disso, desenvolveu-se uma equação com as variáveis MLG e idade para melhor estimativa da TMR de ciclistas. Recomenda-se, no entanto, que a equação desenvolvida seja validada em estudo envolvendo um número maior de ciclistas, para que...
The resting metabolic rate (RMR) can be determined by indirect calorimetry (IC). However, the clinical estimation of this parameter has been done using mathematical equations, which were developed in studies involving non-athletes. Although some authors have indicated that such equations do not estimate correctly the RMR, they have been constantly used to estimate such parameter and to prescribe diets, including for athletes. The objective of this study was to compare the RMR determined by IC with the ones estimated using the equations proposed by Harris & Benedict (HB), Schofield, FAO/WHO/UNU and Henry & Rees (HR), in 15 male cyclists, aged 24.4±3.68 years, body mass index of 21.97±1.46 kg/m² and VO2max of 70.00±5.32 mL(kg.min)-1. Student's t test (when data presented normal distribution) and Mann-Whitney (when data did not present normal distribution) were used to compare the RMR determined by IC and the ones estimated by the equations. Probability values below 0.05 were considered statistically significant. Pearson bivariate correlation coefficients were calculated to evaluate the relationship between RMR and fat free mass (FFM). It was verified that the RMR was significantly underestimated in 23.5 percent, 16.7 percent, 16.8 percent and 16.9 percent, respectively by the equations proposed by HR, FAO/WHO/UNU, Schofield and HB in comparison to RMR obtained by IC. RMR values were significantly correlated with FFM (r=0.551, p=0.03). These results confirm that the equations evaluated in this study are not appropriate to estimate the RMR of athletes. Such results can be explained by the fact that athletes have more FFM and possibly a greater β- adrenergic receptors response to the sympathetic nervous system, which in turn leads to RMR higher than in sedentary people. Therefore, we created an equation considering the FFM and age variables to better estimate athletesï RMR. However, this equation should be validated in a study involving...