Sex- and endurance training-mediated cardiovascular protection through lipids during exercise

Abstract

Premenopausal women and endurance-trained individuals of either sex have reduced cardiovascular disease (CVD) risk. Endurance training shifts fuel selection towards fats to spare carbohydrates; interestingly, women prioritize fats as an energy resource more than men do during exercise. Relying on fats during exercise drives whole-body lipolysis and promotes lipid uptake and oxidation capacity in skeletal muscles. These metabolic adaptations during exercise result in protection against diet-induced obesity, a healthy body fat distribution, and reduced plasma triacylglycerol (TG) concentrations. Here, we analyze how sex differences and endurance training mediate changes in skeletal muscles, including exercise-induced lipolysis, lipid uptake and β-oxidation, intramuscular TG storage, and postexercise lipid metabolism, and discuss how regulating this processes affects CVD risk.

Keywords: CVD risk; endurance training; intramyocellular triacylglycerol (IMTG); muscle fiber types; post-exercise recovery; sex differences in fuel selection.