When you sleep, you are, in effect, fasting. If you get the adequate sleep that a hard-training bodybuilder should — seven to nine hours per night — you are going a long time without food. You wouldn’t go that long between meals during the day if you wanted to gain muscle mass. Go more than a couple of hours without eating and your blood sugar levels start to fall. Because your brain can run only on sugar (glucose), your body reacts by breaking down muscle protein. It converts amino acids to glucose for your brain to use. In other words, your body is literally eating your muscle mass to fuel your brain.

VERDICT: Fiction

SOLUTION: You should eat before bedtime.

Choose a slow-digesting protein for that time. A protein shake containing casein, particularly one that lists micellar casein, is good because it provides a slow and steady supply of amino acids for up to seven hours. That means it will supply your body with amino acids that can be converted to glucose, and therefore spare your muscle protein. If you take enough, about 40 grams before bedtime, not only will it prevent muscle breakdown, but the extra aminos can be used to stimulate muscle growth while you sleep.


Consider eating some healthy fats, such as two tablespoons of flaxseed oil, two tablespoons of peanut butter or one ounce of mixed nuts. The healthy fats will help to further slow the digestion of the casein protein and help maintain insulin sensitivity. Slow-digesting carbs, like those found in a cup of oatmeal or in two slices of whole-grain bread, make a good addition to protein and healthy fats. These food choices will provide a steady supply of glucose to your brain during the night, which will help prevent the breakdown of muscle protein, and they won’t get stored as fat.