You do want to take in plenty of carbs prior to practice. However, they have to be very low GI and you should eat them 1-2 hours before practice. Sluggishness is due to fluctuations in blood glucose. Loe GI carbs elimintate this problem and provide slow "realease" energy. Eat them long enough so that the bulk doesn't sit in your stomach. Mashed sweet potatos are ideal. They aren't heavy in the stomach, and are very low GI.
Following practice you need to replenish muscle glycogen. For this you need high GI carbs. Liquids are your best bet here as they digest very rapidly providing your muscles with nearly imediate glucose and also water. It's also easier on the stomach as often times you won't be hungry after an event.