Your six pack can be covered by skin and/or fat. Many times, what sits on our stomach has a lot to do with our genes and our habits. Generally, we pick up fat-laying qualities from our parents and/or our relatives. When we work out, we can tone the muscles and use stored fat from anywhere in our bodies but this may or may not affect the fat on our stomach. Working our stomach muscles won't tone loose skin either -- this is heavily influenced by our genes. Hope this helps.