An exercise scientist reveals exactly how long you need to work out to get in great shape

Have a reunion or a wedding coming up, and you'd like to get in top shape before running into your ex? Exercise Scientist Shawn Arent tells us just how long you'll need to lose those pounds. Shawn Arent is the director of the Center for Health and Human Performance at Rutgers University and a Fellow in the American College of Sports Medicine. Follow Tech Insider:On Facebook