Proteomic changes induced by acute exercise and high-intensity interval training during pregnancy: a pilot randomised controlled trial

Physical activity is essential for maternal health during pregnancy, with WHO guidelines recommending at least 150 min of moderate-intensity aerobic physical activity per week. However, there is a lack of data on the impact of higher-intensity exercise during pregnancy, including the potential health effects of high-intensity interval training (HIIT). In this study, we aimed to analyse the changes induced by a cardiopulmonary exercise test (CPET) up to volitional exhaustion and an 8-week HIIT program on the urine proteome of pregnant women, using the SWATH-MS technique and provide insights into molecular processes influenced by HIIT. We recruited 18 women with uncomplicated singleton pregnancies between 13 and 28 weeks of gestation. All women underwent CPET to assess their peak oxygen uptake (VO2 peak), oxygen uptake at the anaerobic threshold (VO2/AT), and heart rate at the anaerobic threshold (HR/AT). Of these women, 9 participated in HIIT sessions three times for 8 weeks and were encouraged to exceed their HR/AT during the exercise intervals. Furthermore, nine women in the EDU group attended educational classes once a week and were advised to engage in moderate to vigorous physical activity independently, in accordance with current recommendations. We observed significant alterations in the urinary proteome after the CPET, with a higher scale of differentially expressed proteins compared to the changes observed after 8 weeks of the HIIT program. Notable changes included proteins involved in calcium ion binding, enzyme inhibitory activity, and immune system pathways, particularly neutrophil degranulation. Proteins such as ARSA, NPC2, MME, and CD177 showed significant regulation, indicating metabolic adaptations and immune responses. The observed downregulation of proteins, such as TFF2, associated with insulin resistance, suggests that HIIT may have potential benefits in preventing gestational diabetes. Our findings demonstrate that while CPET induces immediate metabolic and immune changes, regular HIIT leads to adaptations, reflected in a decrease in the number of altered proteins over time. Further studies are needed to confirm these findings and explore the long-term benefits of HIIT for pregnant women. Nevertheless, this pilot research provides a novel proteomic perspective on the impact of HIIT during pregnancy, underscoring its potential to improve maternal health through targeted metabolic and immune system adaptations.