If you want to lose fat running and cardio are absolutely needed but the biggest thing is lower your calorie intake. If you only burn 2500 calories a day and you take in 3000 you are going to gain weight. You need to be at the point where you are taking in fewer calories than you need. But be careful, what I mean is you have to lower them below the extra calories needed from working out but still satisfying you basic caloric intake for any given day. That way your body will burn the extra fat(stored energy), which means less body fat. Keep your protein high and your carbs regular. Lower your sugars, fats, and impact carbs(beer, etc...).