i myself run after a workout. it does cut into your muscle mass a little but helps in cutting. you really can't get big and lose at the same time, but you can get bigger and lose at the same time. drink your protein right after you get done lifting and before you hit the cardio that will help. Also try to keep you cardio somewhat light and your heartbeat lowered like 120-140 because that will help burn fat, don't go all out sprinting because then your just endurance training, and if your like just about every one else on here you don't want to be a triathlete but bigger and more cut. also sometimes i go to do cardio and just can't becuase my workout wore me out to much, so if you can't don't!!! you don't want to lose any precious muscle cause your pushing yourself to run. remember lifting comes first and then cardio. listen to your body, it will be the best trainer you have, it will tell you what you need and what you can do.