Changes in insulin, leptin, resistin and irisin levels and their associations with blood pressure after an 8-week supervised, online “HIIT Mama” program vs. self-performed moderate-to-vigorous physical activity during pregnancy – A randomized control

We aimed to determine changes in insulin, leptin, resistin, and irisin levels and their associations with blood pressure (BP) during pregnancy, following an 8-week high-intensity interval training (HIIT) or a self-performed moderate-to-vigorous physical activity (MVPA). The study involved 54 Caucasian women in uncomplicated, singleton pregnancy (age 32 ± 4 years, week of gestation 24 ± 4, mean ± SD). They were randomly allocated to the 8-week supervised, online “HIIT Mama” program (HIIT group, n = 34) or educational intervention and self-performed MVPA (EDU group, n = 20). All participants maintained normotension throughout the study. The HIIT program induced a statistically significant increase in insulin (p = 0.005; ES: r = 0.48; IQR: 0.005) and resistin (p < 0.001; ES: r = 0.66; IQR: 1.07). The only significant change presented by the EDU group was the decrease in resistin (p = 0.037; ES: r = 0.47; IQR: 0.82). We observed a trend towards more frequent increases after the HIIT program than after the EDU intervention in insulin (76% vs. 65%, respectively) and in leptin (63% vs. 50%, respectively). There was also a trend towards a more frequent decrease in irisin in the HIIT group than in the EDU group (65% and 53%, respectively). Despite these different responses in both groups, we observed similar associations of selected biomarkers with BP after eight weeks of interventions. In both groups, higher diastolic BP was significantly correlated with higher insulin (HIIT: r = 0.51; p = 0.002 and EDU: r = 0.45; p = 0.05) and leptin (HIIT: r = 0.39; p = 0.03 and EDU: r = 0.62; p = 0.02). We observed no association of resistin and irisin with systolic or diastolic BP in either group. Both prenatal HIIT and MVPA optimize physiological and biochemical responses maintaining normotension, without negatively affecting the course of pregnancy or neonatal outcomes.