Interval training and cardiometabolic health in reproductive-aged females

Take home message

• Interval training, including high-intensity interval training (HIIT) and sprint interval training (SIT), can be an alternative exercise option that is time-efficient and provides multiple health benefits in reproductive-aged females.
• Recent studies indicate that HIIT is safe during pregnancy and is well tolerated by the fetus; however, more research is needed to confidently integrate HIIT into physical activity guidelines for pregnant individuals.

Background

• Physical activity is crucial for female health, particularly during preconception, pregnancy, and postpartum, to improve both maternal and infant health.
• Despite the known benefits, physical inactivity remains high among reproductive-aged females, highlighting the need for practical and enjoyable exercise solutions like interval training.
• Interval training, including HIIT and SIT, is a time-efficient and effective modality that can offer superior cardiometabolic benefits compared to moderate-intensity continuous exercise.

How the study was done

• The participants from the studies reviewed were reproductive-aged females, including those with specific health conditions such as: overweight/obesity, polycystic ovary syndrome (PCOS), and females undergoing artificial reproductive techniques (ART).
• The interventions primarily involved different forms of interval training, including HIIT at ‘near maximal’ efforts and SIT at ‘all-out’ efforts.
• The outcomes measured in the studies included various cardiometabolic and reproductive health parameters such as adiposity, cardiorespiratory fitness, and insulin sensitivity.

What the researchers found

• HIIT and SIT significantly improve cardiorespiratory fitness, insulin sensitivity, and body composition in reproductive-aged females, including those with overweight/obesity and PCOS.
• HIIT can be more effective in improving insulin sensitivity and reducing visceral fat than moderate-intensity continuous training in women with overweight/obesity.
• Based on a small number of studies, HIIT can be safe during pregnancy, and can improve maternal cardiorespiratory fitness and glycemic control without adverse effects on fetal health.

Conclusion

• Emerging evidence suggests that HIIT improves cardiometabolic and reproductive outcomes in reproductive-aged females, including those with obesity, PCOS, diabetes, and gestational diabetes mellitus.
• While HIIT appears safe and beneficial during pregnancy, more research is needed to confirm its safety and effectiveness, particularly in the postpartum period, to better integrate it into physical activity guidelines.