Effect of dietary restriction and/or exercise on 23-h metabolic rate and body composition in female rats.
This study examined the effects of three levels of dietary intake [ad libitum fed (AL), moderately severe (MSR), and severe restriction (SR)] and two levels of exercise [cage confinement (CC) and exercise training (E)] on 23-h resting metabolic rate (RMR) and body composition in 47 female Sprague-Dawley rats. At the end of the 9-wk study, the MSR and SR groups weighed approximately 81 and 61%, respectively, of the AL-CC group. RMR was depressed for the MSR and SR groups compared with the AL-CC group. This was true whether expressed on an absolute (ml/min) or relative (ml.min-1.kg-0.75) basis. On a relative basis, which accounts for changes caused by weight loss alone, the RMR decreased by approximately 12 and 19%, respectively, for the MSR and SR groups compared with the AL-CC group. Although E resulted in significant differences in fat mass, percent fat, percent water, and heart mass between the AL groups, there were no significant differences between E and CC groups at either the MSR or SR level of dietary intake for any of the variables measured (i.e., body composition, muscle mass, RMR). Thus E does not appear to affect the composition of lost weight or RMR during diet-induced weight loss for female rats of normal weight.
Ballor
D L
DL
Department of Human Development Studies, University of Vermont, Burlington 05405-0117.
D000818:Animals; D001823:Body Composition / Q000502:physiology*; D001834:Body Water / Q000502:physiology; D004032:Diet; D005260:Female; D006321:Heart / Q000033:anatomy & histology; D050356:Lipid Metabolism; D009132:Muscles / Q000033:anatomy & histology / Q000378:metabolism / Q000502:physiology; D009929:Organ Size / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology; D010805:Physical Conditioning, Animal; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D011506:Proteins