HIIT Versus MICT on Abdominal Fat Mass and Lipid Oxidation in Postmenopausal Women (MATISSE)

Postmenopausal women, as men, are more prone to central or android obesity than premenopausal women. Abdominal fat mass accumulation is associated with an increase of cardiovascular disease (CVD) risk. Most exercise programs designed for weight loss have focused on about 30 min several times per week of moderate intensity continuous training (MICT). Disappointingly, such exercise programs have led to either none or low fat loss. Accumulating evidence suggests that high intensity interval training (HIIT) should be an effective exercise protocol for reducing body fat of overweight individuals, especially at the abdominal level. Resistance Training (RT) is associated with increased muscle mass and strength gain in main muscles groups. Thus, RT seems to be an interesting strategy to fight against deconditioning and autonomy loss with age. Development of muscle mass enhances resting metabolism rate. Thus, RT could raise daily energy expenditure ie. substrates' oxidation including lipids. The aim of our study was to compare the effects of a 12-week moderate intensity continuous training (MICT) program with high intensity interval training (HIIT) program combined or not with a resistance training (RT) program on total abdominal and visceral fat mass and substrate utilization in postmenopausal women. It is hypothesized that HIIT compared to MICT program would result in significantly greater whole body and regional fat mass losses (abdominal and visceral) and would improve lipid oxidation at rest and during prolonged moderate exercise. It is also hypothesized that HIIT associated with RT could be the best strategy to reduce fat mass.