Background & aims: Non-exercise activity thermogenesis (NEAT) and substrate oxidation are significant components of Energy Balance; their regulation may be modulated according to nutritional status and their impairment has been advocated as a factor facilitating the development of excess body fat. Methods: In this study body composition, resting metabolic rate (RMR), fidgeting as a component of NEAT and respiratory quotient (RQ), an index of preferential substrate oxidation, have been evaluated in 80 young women: 20 restrictive anorexia nervosa (rAN: BMI 15.1+/-1.6 kg/m(2)); 20 constitutional leanness (CL: BMI 17.2+/-1.0); 20 obese patients (Ob: BMI 43.8+/-10.0) and 20 controls (CTR: BMI 21.7+/-2.4). Results: Fat free mass, fat mass and RMR progressively increased from rAN to Ob (p < 0.05). Fidgeting was higher in CL (67.2+/-27.2 kcal; p < 0.05) than in the other groups. Lipid oxidation, evaluated with RQ showed a negative correlation with fidgeting in CL (r=-0.433; p<0.05) and positive in Ob (r=0.572; p<0.05) and in rAN (r=0.434; p<0.05). Conclusion: Our findings support the regulatory function of NEAT, its protective role to prevent excess body fat accumulation and its positive relation with fat oxidation in CL.
BMR variability in women of different weight
Montagnese, C.Writing – Original Draft Preparation
;
2007
Abstract
Background & aims: Non-exercise activity thermogenesis (NEAT) and substrate oxidation are significant components of Energy Balance; their regulation may be modulated according to nutritional status and their impairment has been advocated as a factor facilitating the development of excess body fat. Methods: In this study body composition, resting metabolic rate (RMR), fidgeting as a component of NEAT and respiratory quotient (RQ), an index of preferential substrate oxidation, have been evaluated in 80 young women: 20 restrictive anorexia nervosa (rAN: BMI 15.1+/-1.6 kg/m(2)); 20 constitutional leanness (CL: BMI 17.2+/-1.0); 20 obese patients (Ob: BMI 43.8+/-10.0) and 20 controls (CTR: BMI 21.7+/-2.4). Results: Fat free mass, fat mass and RMR progressively increased from rAN to Ob (p < 0.05). Fidgeting was higher in CL (67.2+/-27.2 kcal; p < 0.05) than in the other groups. Lipid oxidation, evaluated with RQ showed a negative correlation with fidgeting in CL (r=-0.433; p<0.05) and positive in Ob (r=0.572; p<0.05) and in rAN (r=0.434; p<0.05). Conclusion: Our findings support the regulatory function of NEAT, its protective role to prevent excess body fat accumulation and its positive relation with fat oxidation in CL.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
