Effect of Weight Cycling in Females (2004)
Group or Institution
Waikato Institute of Technology (Wintec)
Author(s)
Andrea Braakhuis, Jodie Collins, Elaine Rush
Abstract
Background /Aims: Many reports state that repeated weight loss followed by weight gain (weight cycling) causes women to become metabolically efficient and therefore regain weight after dieting. Metabolic efficiency has been observed in obese subjects, but not in normal weight dieters. The aim of this study is to investigate what effect long term weight cycling has on metabolic function and eating behaviour in a normal weight population.
Aims/Method: Subjects were limited to those with similar fat, fat free mass and body weight then grouped by previous weight fluctuates but currently weight stable (weight cyclers) versus those who have remained weight stable (non-weight cyclers). Indirect calorimetry, 7-day nutritional intake and activity, three-factor eating questionnaire and a DEXA scan were performed.
Results: There were no significant differences in resting metabolism, however the weight cyclers were lower (4.8 ± 1.0 versus 5.0 ± 1.1 MJ/day). Restrained eating was different (p=0.04) between non-weight cyclers (3.9 ± 2.9) and weight cyclers (6.7 + 3.7). Disinhibition was different (p=0.03) between non-weight cyclers (5.1 ± 2.2) and weight cyclers (7.8 ± 3.7), but no difference in hunger between groups. Therefore the mentality of dieting still exists in weight cyclers despite no longer engaging in dieting activities.
Self reported daily activity, presented as a multiple of the basal metabolic rate, was higher in the weight cyclers (1.7 ± 0.2) than the non-weight cyclers (1.5 ± 0.2).
Conclusions: Resting metabolic rate did not differ between groups, however will power, resistance to eating cues and daily activity levels did. Therefore, in order for subjects who have dieted to obtain the same body composition they must have compensatory psychological and physical behaviours.
Keywords: Weight cycling, resting metabolic rate, body composition, fat mass, fat free mass