title: Regulation of exercise carbohydrate metabolism by estrogen and progesterone in women.
abstract: To assess the roles of endogenous estrogen (E2) and progesterone (P4) in regulating exercise carbohydrate use, we used pharmacological suppression and replacement to create three distinct hormonal environments: baseline (B), with E2 and P4 low; estrogen only (E), with E2 high and P4 low; and estrogen/progesterone (E + P), with E2 and P4 high. Blood glucose uptake (R(d)), total carbohydrate oxidation (CHO(ox)), and estimated muscle glycogen utilization (EMGU) were assessed during 60 min of submaximal exercise by use of stable isotope dilution and indirect calorimetry in eight eumenorrheic women. Compared with B (1.26 +/- 0.04 g/min) and E + P (1.27 +/- 0.04 g/min), CHO(ox) was lower with E (1.05 +/- 0.02 g/min). Glucose R(d) tended to be lower with E and E + P relative to B. EMGU was 25% lower with E than with B or E + P. Plasma free fatty acids (FFA) were inversely related to EMGU (r(2) = 0.49). The data suggest that estrogen lowers CHO(ox) by reducing EMGU and glucose R(d). Progesterone increases EMGU but not glucose R(d). The opposing actions of E(2) and P(4) on EMGU may be mediated by their impact on FFA availability or vice versa.
authors.affiliation: Department of Exercise Science, University of Massachusetts, Amherst, MA 01003, USA.
authors.forename: Tara M
authors.initials: TM
authors.lastname: D'Eon
authors.forename: Carrie
authors.initials: C
authors.lastname: Sharoff
authors.forename: Stuart R
authors.initials: SR
authors.lastname: Chipkin
authors.forename: Dan
authors.initials: D
authors.lastname: Grow
authors.forename: Brent C
authors.initials: BC
authors.lastname: Ruby
authors.forename: Barry
authors.initials: B
authors.lastname: Braun
mesh_terms: D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D050260:Carbohydrate Metabolism; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology; D004837:Epinephrine / Q000097:blood; D004967:Estrogens / Q000008:administration & dosage*; D015444:Exercise / Q000502:physiology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D006003:Glycogen / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000097:blood; D019344:Lactic Acid / Q000097:blood; D008597:Menstrual Cycle / Q000502:physiology; D009638:Norepinephrine / Q000097:blood; D010084:Oxidation-Reduction; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D011374:Progesterone / Q000008:administration & dosage*; D012146:Rest / Q000502:physiology
chemical_list: D001786:Blood Glucose; D004967:Estrogens; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D019344:Lactic Acid; D011374:Progesterone; D006003:Glycogen; D009638:Norepinephrine; D004837:Epinephrine