Prospective examination of pregnant and nonpregnant women’s physical activity beliefs and behaviours

Abstract

Objective: The purpose was to prospectively assess if the theory of planned behaviour guided physical activity (PA) beliefs and behaviours for pregnant compared to nonpregnant women. Background: Theoretically based prospective studies can advance our understanding and promotion of PA during each trimester of pregnancy. Methods: Participants (N = 81) completed self-report assessments of their PA beliefs and behaviours at Time 1 (first trimester/baseline), Time 2 (second trimester/3 months), and Time 3 (third trimester/6 months). Results: The elicited PA beliefs and behaviours varied by assessment time and group. For the PA beliefs, the nonpregnant women’s (n = 43) salient beliefs were consistent across time. For the pregnant women (n = 38) the beliefs varied across time, with pregnant-specific beliefs that differed by trimester. For example, nausea was a common PA disadvantage reported in the first trimester, compared to increased weight/size in the third trimester; whereas the nonpregnant women reported time as the main disadvantage across all three assessments. For PA behaviour, the nonpregnant women reported more moderate PA than the pregnant women across all three assessments; with the pregnant women’s moderate PA decreasing from the first, to the second, to the third trimester. Conclusion: Trimester-specific PA interventions are encouraged to increase and maintain PA during pregnancy.