Bedtime Story

Weight lifters today are more informed about training and nutrition than they were a decade ago. But as often is the case, a little information can be dangerous. Unfortunately, you and your wallet are the ones in danger in this case.

Take the phenomenon of overnight catabolism, for example. First, you learn what the word catabolic means. It's the opposite of anabolic and has to do with muscle wasting. Then you learn that you become catabolic during sleep at night. As a result, you make it your goal to prevent this catabolism at any cost.

Now here comes the dangerous part. The big bad Knottinghams of the supplement world realize your unnecessary desperation and begin to use this information against you, spinning scientific-sounding tales based on spurious assumptions and false promises. They come as a wolf dressed in sheep's clothing and, unlike the fairy tales of our youth, it becomes difficult to distinguish the heroes from the villains.

Keeping with the overnight catabolism theme, Knottingham's new golden arrow is his so-called "nighttime anti-catabolic protein formula." He's been trying to convince would-be supplement consumers that his super expensive, slow-released protein blends are the only way to prevent wasting away to nothing overnight. Using fancy words and a couple of inappropriate references, he claims that the conventional protein powders on the market today are useless for overnight consumption and that only his special high-tech blend will make you huge.

With furrowed brow, I unsheath my arrow.

When tucking into bed at night, you're about to embark on a six to eight hour journey of rest and repair. After all, it's been a long day in the forest. However, during this time you aren't feeding the body. We call this the post-absorptive period. If you haven't heard of this post-absorptive period before, let me explain.

Throughout the day, the first hour or two after eating is referred to as the post-prandial period. During this time, the body digests and absorbs nutrients. When you eat and even during the post-prandial period, the body's maintenance needs for blood glucose and energy are met. At this time it begins to synthesize proteins and glycogen in the liver and muscle.

Once this period is over, the post-absorptive period sets in. After the absorption of the nutrients from your last meal is complete and the nutrients in the blood have been delivered, the body begins using those stored nutrients for energy. Then, in order to maintain blood glucose and tissue metabolism, the liver and muscle start metabolizing and sending glucose and amino acids out into the blood.

If you're eating frequently during the day, the overnight period is your longest post-absorptive period. It should be no surprise that after an overnight fast and a long post-absorptive period, some of the muscle glycogen and muscle protein will have been depleted. In fact, research has verified this hypothesis and shown specifically that after the overnight fast, muscle protein breakdown exceeds muscle protein synthesis. Interestingly, the opposite is true in the splanchnic region (gut, liver, etc) because in these tissues, synthesis exceeds breakdown. Therefore during the night, muscle is broken down to feed the gut/liver/etc and presumably other tissues as well (1).

Nuts and Berries of the Forest Won't Do It

Understanding what happens after an overnight fast, I'm sure you're now wondering how you might keep out of the post absorptive period and prevent overnight muscle losses. Well, the secret is in understanding how the body handles protein and amino acids under normal conditions. Remember, net muscle-protein status (anabolism or catabolism) is determined by a simple equation: protein synthesis minus protein breakdown.

Large increases in blood amino acid levels (100-200% above the fasted baseline) are necessary for increasing protein synthesis. Therefore a protein meal containing at least 20-30 grams of fast-digesting protein (like whey) can accomplish such a goal.

Interestingly, to inhibit protein breakdown we only need small increases in blood amino-acid levels (25-50% above fasted baseline). However, these small increases must be prolonged (4-5 hours) in order to realize this inhibition of protein breakdown. In this situation, a slow-digesting protein like casein is necessary.

So, at this point you might be asking why you can't simply consume whey protein every few hours in order to maintain super-high levels of blood amino acids. It makes sense that this would keep amino acid levels high for a very long period of time, thus stimulating protein synthesis and preventing protein breakdown, right? Well, not so fast, Little John.

Unfortunately, when large increases in blood amino acid levels (+100%) are achieved via intravenous infusion for a prolonged period of six hours, protein synthesis only increases from the 30 minute to the two-hour mark. After two hours, protein synthesis rates almost immediately return to baseline. Unbelievably, protein synthesis rates remain at baseline levels from the two hour to the six hour marks, even with the same level of hyperaminoacidemia (2).

So it's clear that keeping amino acid levels elevated all day won't keep protein synthesis rates racing along. It's my guess that if you were to try to do this, breakdown would simply balance synthesis and you wouldn't get any bigger. It's my theory that you need those phasic bursts in amino-acid levels to stimulate protein synthesis.

If you're keeping up, this presents a confusing picture as to how to time your meals for optimal protein growth. In my opinion, large bursts of hyperaminoacidemia every four hours or so (to stimulate synthesis in a phasic manner), coupled with a prolonged low-level hyperaminoacidemia (to chronically inhibit breakdown) may be the best way to coerce the muscles into getting huge. So how can you accomplish this? That's easy, at least when you're awake.

Consider the "pros" and "cons" of the bodybuilder's two main sources of protein:

1. Whey protein intake (30g) produces large transient hyperaminoacidemia. After an hour, blood amino acids are elevated by about 300%. After two hours, about 92%. After four hours, you're back to baseline. This is ideal for increased protein synthesis but does nothing for protein breakdown (3,4).
2. Casein protein intake (30g) produces moderate but prolonged hyperaminoacidemia. After two hours, blood amino acids are elevated by about 32% and after four hours by about 35%. After seven hours, blood amino acids are still elevated. This is ideal for prevention of protein breakdown but does nothing for protein synthesis (3,4).

The next question is, where the heck are you gonna find whey and casein protein in Sherwood Forest? Well, if you can find a cow or a goat, you're in luck.

Milk protein is composed of 80% casein and 20% whey. Milk is interesting in that, believe it or not, the whey and casein fractions are absorbed separately. In one study, subjects consumed skimmed milk and were evaluated over the course of eight hours. With milk-protein ingestion, there's a rapid rise in blood amino acids within one hour (probably as a result of the whey fraction), a plateau from one to three hours (a combination of simultaneous whey and casein absorption), and then there's a progressive decline over the course of the next eight hours. However, blood amino acids are still elevated at the eight hour point as a result of the casein fraction. (5).

While this discussion has only dealt with milk proteins, it may be safe to say that most animal proteins are probably similar to casein in their slow digestion and absorption profiles. So, during the day, eating a combination of fast digesting and slow-digesting proteins every four hours or so is probably the best way to maintain a highly positive daily protein status. Again, this can be done with milk proteins alone or with a combination of whey or milk protein and animal protein at each meal.

In the end, though, don't get too obsessed with seeking out your favorite cow every four hours. Research has shown that eating animal protein alone does a nice job of increasing post-prandial protein synthesis, too.

All these recommendations are interesting for the waking hours while you're robbing from the rich, but what about at night when bedding down with the lovely Maid Marian?

Well, if I had an ideal nighttime protein shake to set by the bed, it would include a combination of ingredients that promotes two large bursts of hyperaminoacidemia every four hours (leading to two bursts of synthesis – one at bedtime and one four hours later) and a prolonged low-level hyperaminoacidemia (to inhibit breakdown). Now, part of this can be accomplished with a milk-isolate blend taken immediately before bed. There are many such blends on the market.

At this point, you might be asking yourself why I simply don't recommend milk. Well, I'm hesitate to suggest milk as a result of the recent data showing that unfermented, intact milk (skim or whole) may not be all that great for you. The high incidence of milk allergies and lactose intolerance coupled with a huge insulin index makes me hesitant to give my endorsement to the moo juice. However, milk products like cottage cheese behave differently than milk and are another solid choice. The whey content of cottage cheese could use some beefing up though, so don't be afraid to throw in some whey or milk isolates.

Although quite effective, unfortunately this route doesn't allow for the second burst of fast protein and hyperaminoacidemia that we want about four hours into our slumber. So the simplest way to do this would be to make a big shake/meal before bed, consume half at bedtime and the other half in the middle of the night.

You can certainly wake up in the middle of the night to provide the body with some protein nutrition, but some people believe doing so will disturb sleep patterns and in the long run, you'll be worse for the waking. So why not formulate a special high-tech protein powder that will accomplish our goal of two large bursts of hyperaminoacidemia every four hours (two bursts of synthesis – one at bedtime and one four hours later) and a prolonged low-level hyperaminoacidemia (to inhibit breakdown) without having to wake up to get it?

Such a formula might contain 15g of regular whey protein, 30g of casein, and 15g of time-released, encapsulated whey protein that sits around in the gut for four hours and is magically released during one big digestive burst at that time. With such a formula, the 60g protein dose would definitely keep you covered for the overnight fast and might help you pack on a little extra muscle.

Excited yet? Well, don't fall for the trap. I'm sorry to tell you that such a formula is probably impossible to make. First of all, I'm not aware of any technology that will allow such a precision release of protein at a predetermined time. Secondly, if there were a way to do this, the costs would certainly be prohibitive.

But what about the current crop of overnight protein formulas popping up in magazine ads? What are they supposed to do? Well, unfortunately they don't even claim to accomplish the goals I set out above. All they claim to do is provide you with a slow released protein that keeps blood levels of amino acids low and stable all night, thus minimizing protein breakdown. Considering that plain old cottage cheese can accomplish this goal, these formulations aren't so revolutionary.

In fact, either milk protein blends or homemade whey/casein combinations may even be superior to slow digesting proteins alone, as indicated above. The combination of fast and slow may be best for both increasing muscle protein synthesis and preventing muscle protein breakdown. So why the need for fancy overnight protein products? At a price of four to seven bucks per 50g of protein (based on the brands I've looked at), I can't see one. All I can see is the rich robbing from the misinformed poor.

To summarize this little bedtime story:

• About halfway through the night your body runs out of muscle-building fuel and leaves you in a catabolic state. To prevent this, it's a good idea to get some protein before bed.
• The so-called "nighttime anti-catabolic protein formulas" hitting the market are overpriced, overhyped, and aren't even ideal for battling catabolism.
• A better and more-affordable choice is plain old cottage cheese and/or a blend of proteins like those found in Metabolic Drive® Protein (Milk itself isn't a good choice however.)

Armed with these arrows of information, I'll now let you go do battle with catabolism and all those unscrupulous Sheriff of Knottinghams out there. Now, where'd that little muffin Maid Marian run off to?

1. Meek SE et al. Differential regulation of amino acid exchange and protein dynamics across splanchnic and skeletal muscle beds by insulin in healthy human subjects. Diabetes. 1998 Dec;47(12):1824-35.
2. Bohé J et al. Latency and duration of stimulation of human muscle protein synthesis during continuous infusion of amino acids. Journal of Physiology. 2001 Apr;532(2):575-579.
3. Dangin M et al. The digestion rate of protein is an independent regulating factor of postprandial protein retention. Am J Physiol Endocrinol Metab. 2001 Feb;280(2):E340-8.
4. Boirie Y et al. Slow and fast dietary proteins differently modulate postprandial protein accretion. Proc Natl Acad Sci USA. 1997 DEC;94:14930-14935.
5. Bos C et al. Assessment of net postprandial protein utilization of N-labelled milk nitrogen in human subjects. British Journal of Nutrition. 1999 APR;81(3):221-226.