title: Physical activity, sedentary behaviors, and estimated insulin sensitivity and secretion in pregnant and non-pregnant women.
abstract: BACKGROUND
  Overweight and obesity during pregnancy raise the risk of gestational diabetes and birth complications. Lifestyle factors like physical activity may decrease these risks through beneficial effects on glucose homeostasis. Here we examined physical activity patterns and their relationships with measures of glucose homeostasis in late pregnancy compared to non-pregnant women.
  
  
  METHODS
  Normal weight and overweight women without diabetes (N = 108; aged 25-35 years) were studied; 35 were pregnant (in gestational weeks 28-32) and 73 were non-pregnant.Insulin sensitivity and β-cell response were estimated from an oral glucose tolerance test. Physical activity was measured during 10-days of free-living using a combined heart rate sensor and accelerometer. Total (TEE), resting (REE), and physical activity (PAEE) energy expenditure were measured using doubly-labeled water and expired gas indirect calorimetry.
  
  
  RESULTS
  Total activity was associated with reduced first-phase insulin response in both pregnant (Regression r2 = 0.11; Spearman r = -0.47; p = 0.007) and non-pregnant women (Regression r2 = 0.11 Spearman; r = -0.36; p = 0.002). Relative to non-pregnant women, pregnant women were estimated to have secreted 67% more insulin and had 10% lower fasting glucose than non-pregnant women. Pregnant women spent 13% more time sedentary, 71% less time in moderate-to-vigorous intensity activity, had 44% lower objectively measured total activity, and 12% lower PAEE than non-pregnant women. Correlations did not differ significantly for any comparison between physical activity subcomponents and measures of insulin sensitivity or secretion.
  
  
  CONCLUSIONS
  Our findings suggest that physical activity conveys similar benefits on glucose homeostasis in pregnant and non-pregnant women, despite differences in subcomponents of physical activity.
authors.affiliation: Genetic Epidemiology and Clinical Research Group, Department of Public Health and Clinical Medicine, Section for Medicine, Umeå University Hospital, Umeå, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Gradmark
authors.forename: Jeremy
authors.initials: J
authors.lastname: Pomeroy
authors.forename: Frida
authors.initials: F
authors.lastname: Renström
authors.forename: Susanne
authors.initials: S
authors.lastname: Steiginga
authors.forename: Margareta
authors.initials: M
authors.lastname: Persson
authors.forename: Antony
authors.initials: A
authors.lastname: Wright
authors.forename: Les
authors.initials: L
authors.lastname: Bluck
authors.forename: Magnus
authors.initials: M
authors.lastname: Domellöf
authors.forename: Steven E
authors.initials: SE
authors.lastname: Kahn
authors.forename: Ingrid
authors.initials: I
authors.lastname: Mogren
authors.forename: Paul W
authors.initials: PW
authors.lastname: Franks
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D004734:Energy Metabolism / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D005951:Glucose Tolerance Test; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism / Q000502:physiology; D018670:Monitoring, Ambulatory; D011247:Pregnancy / Q000378:metabolism / Q000502:physiology*; D012044:Regression Analysis; D057185:Sedentary Behavior
chemical_list: D001786:Blood Glucose; D007328:Insulin