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.Design/Patients/Measurements-851 women underwent a glucose challenge test (GCT) and a 3-hr oral glucose tolerance test (OGTT) in late pregnancy, yielding 4 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 3 component domains: work, non-sport 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 non-sport 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).
CIHR Author Manuscript
CIHR Author Manuscript
CIHR Author ManuscriptConclusions-Pre-gravid vigorous/sports activity is associated with a reduced risk of glucose intolerance in pregnancy, an effect likely mediated by enhanced insulin sensitivity.