Find out how many calories that you should be taking in and eat good carbs ( low glycemic ) and good protein. You will need to increase your protein as you increase your muscle so that your body uses the protein for that muscle. If you are not eating enough calories for your body and increased work load, your body will use that protein for fuel, robbing it from your muscles. This you do not want. Make sure that your cardio is intense, meaning, push yourself beyond your comfort zone and challenge yourself. This will help you to burn more calories. Again, you have to be aware of how many calories your body needs to sustain it and your cardio expenditure.