depends what your goals are
cardio to lose weight is best done in the AM prior of you eating much carbs at all
http://www.bodybuildingforyou.com/ar...s-fat-loss.htm you will be shocked at how much fat you will burn doing this
now to build muscle is thats your goal with weight training you need to eat a good pre meal and post mean and def needs to include carbs
your best bet is dedicate days or do day and night split and read the above link