Drinking water is necessary when playing sports, especially in warm climates. As bodies undergo physical exertion they begin to sweat. As this sweat evaporates it cools our bodies down. If we do not have enough fluids in us this process cannot happen which leads to dangerous circumstances.
The same principle applies to our spiritual well-being. We have got to stay hydrated with Christ, the living water. Christ said of Himself, "But whosoever drinketh of the water that I shall give him shall never thirst; but the water that I shall give him shall be in him a well of water springing up into everlasting life."