Even in the midst of his hectic schedule, actor Ji Sung managed to lose close to 30 lbs (13kgs) in just three weeks! He likes to work out whenever he finds some spare time, and his workout consists of 40 minutes of running on the treadmill along with 20 minutes of weight training. "There is a restaurant near our shooting premises which I frequently dine at. The restaurant accurately calculates the number of calories per dish and so it's been helpful to my diet," the actor said. A source close to the actor also commented, "Ji Sung is in tip-top shape. He doesn't run - he sprints at full speed. I ran track and field in my day, but even I can't keep up with him." Ji Sung plays the role of 'Cha Ji Hun' in the SBS drama 'Protect the Boss' that airs every Wednesday and Thursday at 9:55PM KST. Source: TV Report via Nate