
Hydration doesn't mean pounding a water or gatorade right before the game. Rather, drinking good fluids throughout the day!
Here is a great article that explains how dehydration affects the body. For example, did you know that dehydration can reduce your athletic performance by 7%- 60%? and, if you wait until you feel thirsty to drink you will still be 25-50% dehydrated after you quench your thirst!
Check it out: http://www.livestrong.com/article/531789-dehydration-in-sports-performance/