HIIT and MICT exercise protocols compared for maternal and child health during pregnancy

Inactivity during pregnancy and postpartum is recognized as a significant health risk, contributing to conditions like gestational diabetes, excessive weight gain, lipid disorders, hypertension, preeclampsia, and depressive symptoms. It also increases the risk of functional and structural disorders such as stress urinary incontinence, back pain, and diastasis recti abdominis (DRA). For children, maternal inactivity can lead to premature delivery, miscarriage, fetal macrosomia, and metabolic disorders. While regular exercise is known to mitigate these risks, the specific benefits of high-intensity interval training (HIIT) during pregnancy remain underexplored compared to moderate-intensity continuous training (MICT). This study aims to fill this knowledge gap.

This study is a protocol for a randomized controlled trial involving pregnant women, who will be divided into three groups: a HIIT group, a MICT group, and an educational program control group. Participants will receive standard obstetric care throughout the study. The exercise programs will be implemented during pregnancy and after childbirth. Comparative groups will also include non-pregnant women. Primary endpoints include selected biological and psychological parameters of mothers, and health parameters of their children. Secondary outcomes include postpartum weight retention, mental well-being, and symptoms of depression assessed at inclusion, gestational week 35-37, eight weeks postpartum, and one year postpartum. Functional parameters like urinary incontinence, back pain, and DRA will also be evaluated.

The study's primary hypothesis posits that HIIT, as a stronger exercise stimulus, will yield superior outcomes on selected biological and psychological parameters of mothers and health parameters of their children compared to MICT. This includes better preventive effects on pregnancy complications and non-communicable diseases in these populations. The second hypothesis suggests that HIIT and MICT, when tailored to the perinatal period, will not significantly differ in their effectiveness for maintaining normal functional parameters in women, specifically in preventing conditions like urinary incontinence, back pain, and diastasis recti abdominis (DRA).

Key secondary outcomes to be measured include postpartum weight retention, mental well-being, and symptoms of depression at multiple time points: at inclusion, gestational weeks 35-37, eight weeks after delivery, and one year after delivery.