Since casein protein slowly enters the blood stream, it has very little impact on protein synthesis. It does however have a powerful effect in suppressing protein breakdown.

In other words, it’s an awesome muscle-sparing protein. Muscle growth is dependent on the balance of protein synthesis and protein breakdown.

To tip the balance in your favour, you want to increase protein synthesis and decrease protein breakdown. You can achieve this by supplementing with whey protein (fast absorption/promotes protein synthesis) and casein protein (slow absorption/suppresses protein breakdown).

To effectively take advantage of whey and casein proteins, you need to use them at the right times of the day. Casein protein is the only protein you should be taking before going to sleep. The reason is because your body needs to be sustained for six to eight hours during your sleep without food. You don’t want your hard-earned muscle being broken down in your sleep, so a protein that is slowly released over time is best.

If you took whey protein before going to bed, it would do very little since whey is absorbed and used so quickly.

Whey protein should be used first thing in the morning and after workouts. If you have to go more than three hours without food during the day or are taking a protein shake as a meal replacement, you should use a blend of whey and casein about 50/50. This will give you a quick shot of protein and a sustained release of protein to carry you through to your next meal.

Finally, if you are eating every two to three hours, you can use whey protein by itself in between meals.