Originally Posted by Clint
You've got the right idea. Basically eat more. What you might want to do is add a carb & protein drink after any intense lacross games/practices. Do 2:1 high GI carbs to whey protein - Either buy some dextrose from the health food store and mix it with whey or combine gatorade and whey. That will help prevent any muscle loss and add some addition calories to your diet. If that isn't enough add a casein shake (like muscle milk) before bed.
That's some excellent advice.
In addition to loosing water weight you will be loosing muscle glycogen which can contribute to a significant amount of the weight you are loosing.
Depending on when your playing you game (at night or during the day) I would recommend a 2:1 or 3:1 carb to protein ratio. 3:1 being for after a day time game.
You may also want to try supplementing with 30mg of Zinc before bed time to keep your energy and hormone levels in check. Hard training athletes almost always have a Zinc deficiency. There is an oral test you can take to asses the deficiency but you would need to visit a homeopath/or naturopathy to do it.
Chocolate milk would be an excellent choice for a night time game. It's a little higher than 2:1 but the casein in the milk would slow the protein absorption for a sustained feeding effect throughout the night. Try 500ml-1 litre post game/practice.
During the day you can mix a whey protein powder and some simple sugar like dextrose in the 3:1 ratio aiming for 15-25grams of protein immediately after the game. Around 1-2 hours later have another shake of similar mix or have a whole meal of meat and some vegetables.