The sports drinks have too much sugar/calories. Many protein shakes have too much sugar too, so read your labels.
Water. Maybe add a splash of fruit juice.
Specifically, Smart Water is a good choice because it has added electrolytes, but not the sugars and calories.
Protein drinks are good before and after workouts. They give an energy boost before a workout. Also, restore muscles after a workout. Water is most preferable during workouts. You have to stay hydrated while working out.