title: Pre-gravid physical activity and reduced risk of glucose intolerance in pregnancy: the role of insulin sensitivity.
abstract: OBJECTIVE
  Pre-gravid physical activity has been associated with a reduced risk of gestational diabetes mellitus (GDM), although neither the types of exercise nor the physiologic mechanisms underlying this protective effect have been well-studied. Thus, we sought to study the relationships between types of pre-gravid physical activity and metabolic parameters in pregnancy, including glucose tolerance, insulin sensitivity and beta-cell function.
  
  
  METHODS
  A total of 851 women underwent a glucose challenge test (GCT) and a 3-h oral glucose tolerance test (OGTT) in late pregnancy, yielding four glucose tolerance groups: (i) GDM; (ii) gestational impaired glucose tolerance (GIGT); (iii) abnormal GCT with normal glucose tolerance on OGTT (abnormal GCT NGT); and (iv) normal GCT with NGT on OGTT (normal GCT NGT). Pre-gravid physical activity was assessed using the Baecke questionnaire, which measures (i) total physical activity and (ii) its three component domains: work, nonsport leisure-time, and vigorous/sports activity.
  
  
  RESULTS
  Glucose tolerance status improved across increasing quartiles of pre-gravid total physical activity (P = 0.0244). Whereas neither work nor nonsport leisure-time activity differed between glucose tolerance groups, pre-gravid vigorous/sports activity was significantly higher in women with normal GCT NGT compared to women with (i) abnormal GCT NGT (P = 0.0018) (ii) GIGT (P = 0.0025), and (iii) GDM (P = 0.0044). In particular, vigorous/sports activity correlated with insulin sensitivity (measured by IS(OGTT)) (r = 0.21, P < 0.0001). Furthermore, on multiple linear regression analysis, pre-gravid vigorous/sports activity emerged as a significant independent predictor of IS(OGTT) in pregnancy (t = 4.97, P < 0.0001).
  
  
  CONCLUSIONS
  Pre-gravid vigorous/sports activity is associated with a reduced risk of glucose intolerance in pregnancy, an effect likely mediated by enhanced insulin sensitivity.
authors.affiliation: Leadership Sinai Centre for Diabetes, Mount Sinai Hospital, Toronto, Canada.
authors.forename: Ravi
authors.initials: R
authors.lastname: Retnakaran
authors.forename: Ying
authors.initials: Y
authors.lastname: Qi
authors.forename: Mathew
authors.initials: M
authors.lastname: Sermer
authors.forename: Philip W
authors.initials: PW
authors.lastname: Connelly
authors.forename: Bernard
authors.initials: B
authors.lastname: Zinman
authors.forename: Anthony J G
authors.initials: AJ
authors.lastname: Hanley
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D016640:Diabetes, Gestational / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D018149:Glucose Intolerance / Q000453:epidemiology* / Q000503:physiopathology*; D005951:Glucose Tolerance Test; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D050417:Insulin-Secreting Cells / Q000502:physiology; D016014:Linear Models; D009043:Motor Activity / Q000502:physiology*; D011247:Pregnancy / Q000502:physiology*; D011248:Pregnancy Complications / Q000453:epidemiology / Q000503:physiopathology; D012307:Risk Factors
references.citation: Diabetes Care. 2006 Oct;29(10):2223-30
references.pmid: 17003297
references.citation: Diabetes Care. 2000 Apr;23(4):460-4
references.pmid: 10857935
references.citation: Diabetes. 2005 Aug;54(8):2404-14
references.pmid: 16046308
references.citation: Acta Physiol (Oxf). 2008 Jan;192(1):127-35
references.pmid: 18171435
references.citation: Acta Obstet Gynecol Scand. 2007;86(11):1290-6
references.pmid: 17851805
references.citation: N Engl J Med. 1999 Dec 2;341(23):1749-56
references.pmid: 10580075
references.citation: Diabetes. 1979 Dec;28(12):1039-57
references.pmid: 510803
references.citation: Epidemiology. 2006 Jan;17(1):31-7
references.pmid: 16357592
references.citation: Diabetes Care. 2001 Sep;24(9):1602-7
references.pmid: 11522706
references.citation: N Engl J Med. 2002 Feb 7;346(6):393-403
references.pmid: 11832527
references.citation: Diabetologia. 1985 Jul;28(7):412-9
references.pmid: 3899825
references.citation: Diabetologia. 2001 Aug;44(8):972-8
references.pmid: 11484073
references.citation: Diabetes Care. 2005 May;28(5):1207-8
references.pmid: 15855591
references.citation: Am J Physiol Endocrinol Metab. 2007 Jul;293(1):E421-7
references.pmid: 17488807
references.citation: Arch Intern Med. 2006 Mar 13;166(5):543-8
references.pmid: 16534041
references.citation: Clin Endocrinol (Oxf). 2007 Nov;67(5):754-60
references.pmid: 17608815
references.citation: Diabetes Care. 2003 Jul;26(7):2005-9
references.pmid: 12832303
references.citation: Med Sci Sports Exerc. 2000 Sep;32(9 Suppl):S498-504
references.pmid: 10993420
references.citation: Diabetologia. 2005 May;48(5):993-1001
references.pmid: 15778860
references.citation: Diabet Med. 2007 Mar;24(3):245-52
references.pmid: 17305786
references.citation: Med Sci Sports Exerc. 1997 Jun;29(6 Suppl):S1-205
references.pmid: 9243481
references.citation: Diabet Med. 1995 Oct;12(10):931
references.pmid: 8846687
references.citation: Eur J Clin Nutr. 2007 Jun;61(6):736-42
references.pmid: 17180158
references.citation: Diabetes Care. 1997 May;20(5):867-71
references.pmid: 9135958
references.citation: Diabetes Care. 2008 Oct;31(10):2026-31
references.pmid: 18628572
references.citation: Diabetologia. 2006 Nov;49(11):2604-13
references.pmid: 16957814
references.citation: Diabetes Care. 2002 Oct;25(10):1862-8
references.pmid: 12351492
references.citation: Diabetes Care. 2004 Mar;27(3):799-800
references.pmid: 14988306
references.citation: J Clin Invest. 2005 Mar;115(3):485-91
references.pmid: 15765129
references.citation: Paediatr Perinat Epidemiol. 2008 Jan;22(1):47-59
references.pmid: 18173784
references.citation: Am J Epidemiol. 2004 Apr 1;159(7):663-70
references.pmid: 15033644
references.citation: Obstet Gynecol. 2006 Nov;108(5):1200-7
references.pmid: 17077243
references.citation: Diabetes Care. 1999 Sep;22(9):1462-70
references.pmid: 10480510
references.citation: Diabetes Care. 2008 Jul;31(7):1275-81
references.pmid: 18356402
references.citation: Gynecol Endocrinol. 2008 Apr;24(4):224-9
references.pmid: 18382910
references.citation: Am J Clin Nutr. 1982 Nov;36(5):936-42
references.pmid: 7137077
references.citation: Diabetologia. 2003 Jan;46(1):3-19
references.pmid: 12637977
references.citation: Diabetes. 2002 Sep;51(9):2796-803
references.pmid: 12196473
references.citation: Diabetes Care. 2007 Jul;30 Suppl 2:S134-40
references.pmid: 17596461
references.citation: J Clin Endocrinol Metab. 2004 May;89(5):2306-11
references.pmid: 15126557