Exercise counteracts declines in lipolysis and fat oxidation after
dietary-induced weight loss in obese, postmenopausal women.
Nicklas, Barbara J., Ellen M. Rogus, and Andrew P. Goldberg.
Division of Gerontology, Department of Medicine, University of
Maryland, and the Geriatric Research, Education, and Clinical Center
(GRECC), Geriatrics Service, Baltimore Veterans Administration
Medical Center, Baltimore, MD 21201
APStracts 4:0080E, 1997.
Weight loss (WL) by hypocaloric diet decreases adipocyte lipolysis and
fat oxidation, adaptations which might predispose individuals to
regain weight. Our hypothesis was that the addition of endurance
exercise (EX) to dietary-induced WL (6 mo; 250-350 kcal/d deficit)
would prevent declines in abdominal (ABD) and gluteal (GLT) adipocyte
lipolysis and fat oxidation in obese, older women. At baseline, the
WL (n=9) and WL+EX (n=11) groups had similar body composition, fat
distribution, aerobic fitness (VO2max), and resting fat metabolism.
Reductions in body weight (WL=11%, WL+EX=8%), percent body fat and
intra-abdominal fat area with the interventions were similar in both
groups, but VO2max increased (9%, P<0.01) only in the WL+EX group.
Basal, adrenergic receptor- and post-receptor-stimulated lipolysis in
ABD and GLT adipocytes decreased (20-70%, P<0.05) in the WL group,
but did not change in the WL+EX group. Fat oxidation decreased (38%,
P<0.05) in the WL group, but not in the WL+EX group. The changes in
fat oxidation and GLT lipolysis differed significantly between
groups. Fat oxidation correlated positively with ABD and GLT
adipocyte basal lipolysis at baseline (r=0.45 & r=0.53, P<0.05),
and the changes in fat oxidation with the interventions correlated
positively with changes in ABD and GLT adipocyte basal lipolysis
(r=0.50, & r=0.42, P<0.05) in the entire group of women. These
results indicate that exercise counteracts the decline in fat
oxidation with WL, in part by maintaining adipocyte lipolytic
responsiveness in some weight-reduced, postmenopausal women.
Received 29 January 1997; accepted in final form 25 March 1997.
APS Manuscript Number E42-7.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 15 April 1997