Simard Laurence, Girard Stéphanie, Lemoyne Jean, Babineau Véronique, Ruchat Stephanie-May
Department of Human Kinetics, Université du Québec à Trois-Rivières, Trois-Rivières, Canada.
Department of Obstetrics and Gynecology of CIUSSS de la Mauricie et du Centre-du-Québec, affiliated with the Université de Montréal, Trois-Rivières, Canada.
Health Psychol Behav Med. 2025 Feb 27;13(1):2468841. doi: 10.1080/21642850.2025.2468841. eCollection 2025.
Physical activity (PA) provides maternal and fetal health benefits, but only 27.5% of Canadian pregnant women meet PA recommendations. Theory-based interventions like the theory of planned behavior (TPB) are useful in explaining what drives behavior. The first objective of this study was to validate the TPB model to predict prenatal moderate-to-vigorous physical activity (MVPA), including testing of the novel interaction between intention and perceived behavioral control (PBC). The second objective was to identify which specific beliefs predict intention toward prenatal MVPA to support intervention.
We used a prospective correlational design. Healthy pregnant women completed two electronic questionnaires: at baseline, to assess TPB constructs, and one month later, to assess MVPA practice. Structural equation modeling was conducted with Latent Moderated Structural Equations. The interaction was interpreted with the pick-a-point method and the Johnson-Neyman graphical method.
The sample consists of 193 women ( = 31.2±3.6). Results indicate that prenatal MVPA at one month was marginally predicted by intention ( = 0.149; < 0.10) and PBC ( = 0.322; < 0.05, MVPA = 20%), but when their interaction was added to the model, MVPA increased to 44%. Specifically, the relationship between intention and MVPA is stronger when PBC is high (0.5 standard deviation over the mean). In the full model including the interaction, attitude ( = 0.59; < 0.001), subjective norm ( = 0.20; < 0.01) and PBC ( = 0.26; < 0.05) all made a significant contribution to predicting MVPA intention ( = 88%). Finally, the following beliefs displayed significant indirect paths toward the intention of being physically active: behavioral beliefs: unlikely to be more tired and likely feel better mentally; normative beliefs: approval from friends and from mother/father; and control beliefs: being tired and missing social support.
Interventions aiming to promote regular MVPA during pregnancy should prioritized the six significant beliefs identified to significantly predict intention toward prenatal MVPA.
体育活动对母婴健康有益，但只有27.5%的加拿大孕妇达到体育活动建议标准。基于理论的干预措施，如计划行为理论（TPB），有助于解释行为的驱动因素。本研究的首要目标是验证TPB模型以预测产前中等至剧烈体育活动（MVPA），包括对意图与感知行为控制（PBC）之间新型相互作用的测试。第二个目标是确定哪些具体信念可预测产前MVPA的意图，以支持干预措施。
我们采用前瞻性相关设计。健康孕妇完成两份电子问卷：一份在基线时用于评估TPB结构，另一份在一个月后用于评估MVPA实践情况。使用潜在调节结构方程进行结构方程建模。采用选点法和约翰逊 - 内曼图形法解释相互作用。
样本包括193名女性（平均年龄=31.2±3.6岁）。结果表明，一个月时的产前MVPA在一定程度上可由意图（β=0.149；p<0.10）和PBC（β=0.322；p<0.05，MVPA解释率=20%）预测，但当将它们的相互作用添加到模型中时，MVPA解释率增至44%。具体而言，当PBC较高（高于均值0.5个标准差）时，意图与MVPA之间的关系更强。在包含相互作用的完整模型中，态度（β=0.59；p<0.001）、主观规范（β=0.20；p<0.01）和PBC（β=0.26；p<0.05）均对预测MVPA意图（解释率=88%）有显著贡献。最后，以下信念对体育活动意图显示出显著的间接路径：行为信念：不太可能更疲惫且可能感觉精神状态更好；规范信念：来自朋友以及母亲/父亲的认可；控制信念：感到疲惫和缺少社会支持。
旨在促进孕期规律进行MVPA的干预措施应优先考虑已确定的六个显著信念，这些信念可显著预测产前MVPA的意图。
