During the night your body is 'starved' of protein and can cause catabolism (break down of muscle tissue). You can fight this by adding Casein at night.
My Favorite Casein Recipe:
1.5 scoops Optimum Casein (vanilla)
¼ cup Frozen Berries
¼ cup Whole Oats
½ t Cinnamon
2 packets of Splenda (or your favorite sweetener)
In a bowl, mix casein, berries, cinnamon, and sweetener with enough water to make a thick batter. Top with oats and freeze for approximately 15 minutes or until solid. Be careful not to freeze too long. The consistency should be like ice cream.