Want to blow away your belly without logging months of mind-numbing hours on the treadmill? High Intensity Interval Training (HIIT) will kickstart your metabolism like no other workout, burning more than twice the calories as a lighter and longer session, according to a study from Southern Illinois University. And the total amount of time you need to dedicate to HIIT: 20 minutes. It really is the least time exercising for the biggest results.
In a way, moderate-intensity physical activity is that "magic pill" a lot of people are looking for, because the health benefits go beyond keeping your waistline trim: Not only can it reduce your risk of cancer, stroke, diabetes and heart attacks, but studies have shown that physical activity can significantly improve the moods of patients with major depressive disorders.