whey or whey isolates

yea what atina said, but also add some weight training as well... lifting weight and cardio together will burn more calories than cardio alone, and don't be afraid your nit gonna bulk up...

None, protein is a myth, your body only absorbs a certain lb of protein.. the rest is burned has calorories. Protein does help increase muscle gain , but by changing hormones.. you don't want that.