Gender difference in the effect of body composition on energy metabolism.
OBJECTIVE
The aim of this study was to investigate the relationship between energy expenditure (EE) and fat mass (FM) by using a cross-sectional approach to study the linear relationship between body composition variables and EE phenotypes as well as an intervention design to investigate the effect of body weight loss on energy metabolism in both genders.


METHODS
The correlations and linear relationships between body weight, FM, fat-free mass (FFM) and abdominal fat vs 24 h EE (EE 24) and sleeping metabolic rate (SMR) were compared between 65 men and 35 women, and before and after weight loss in 10 men and 10 women.


RESULTS
Our results showed that for a given FM, men displayed a higher EE than women, independently of FFM. Furthermore, regression analysis revealed that after body weight loss, men displayed a lower SMR for a given FM or FM adjusted for FFM compared to before the treatment, but this was not so in women. However, when FM was adjusted for abdominal fat deposition, the difference between the conditions was no longer observed.


CONCLUSIONS
FM has a significant impact on EE only in men. We suggest that abdominal adipose tissue may exert a potent regulatory effect on energy metabolism which would be more detectable in men who generally store more fat in this compartment than women.
Dionne
I
I
Physical Activity Sciences Laboratory and Lipid Research Center, Laval University, Ste-Foy, Québec, Canada.
Després
J P
JP
Bouchard
C
C
Tremblay
A
A
D000005:Abdomen; D000273:Adipose Tissue; D000328:Adult; D001067:Appetite Depressants / Q000627:therapeutic use; D001481:Basal Metabolism; D001823:Body Composition; D001835:Body Weight; D004734:Energy Metabolism; D005260:Female; D005277:Fenfluramine / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012727:Sex Characteristics; D012890:Sleep / Q000502:physiology; D015431:Weight Loss
D001067:Appetite Depressants; D005277:Fenfluramine