The Religion of Pre and Post Workout Nutrition

The basic non-science summary is: the study found that CAS was good at preventing protein breakdown (proteolysis), but was not so good for increasing protein synthesis. WP had basically the opposite effects: it increased protein synthesis but didn’t prevent protein breakdown. The problem is that they were using fasted subjects for a single meal. ***

Keep that in mind as we move along here…

So far so good right? So what can we conclude from this study and how useful are the results? Like so many studies, the results were interesting—and of little use to people in the real world. Do these results hold up under more “real world” conditions where people are eating every few hours and/or mixing the proteins with other macronutrients (i.e., carbs and fats)?

The answer is probably not, which is exactly what the researchers found when they attempted to mimic a more realistic eating pattern of multiple meals and or the addition of other macronutrients. The follow up study was called “The digestion rate of protein is an independent regulating factor of postprandial protein retention.” Four groups of five to six healthy young men received:

So what did they find? In a nut shell, giving people multiple doses of whey—which more closely mimics how people really eat-—had basically the same effects as a single dose of casein, and mixing either with fats and proteins pretty much nullified any big differences between the two proteins.

Even that’s not the end of the story, however, as multiple follow up studies done by the same group and others found these effects could also be different in older versus younger people and male versus female! How messed up is that?! So how much press did these follow up studies get? Little or none, as I recall.

Now, a later study did attempt to examine the actual net amino acid uptake after resistance training with whey vs. casein, and found both proteins had essentially the same effects on net muscle protein synthesis after exercise despite different patterns of blood amino acid responses.

Does that put to rest the issue or debate of one protein vs. the other post-workout? No, as there are yet more conflicting studies out there and my bet is still on whey as the superior post-workout protein, but it’s important to realize the answer is far from established at this time.

Got Milk?

Milk: nature’s original MRP. Despite all the fancy proteins out there all claiming to be the next step in the evolution of proteins that “will blast you past your plateaus in the gym,” good old milk seems to be competing—and winning—against some “high tech” products on the market. We have various studies finding increased protein synthesis and other positive effects when a purified protein supplement (e.g., whey, soy, casein, etc.) ingested right after or before a workout—usually in conjunction with carbohydrates—but what about good old milk, a “real” food?

One recent study found good old milk to be an effective post-workout drink that increased net muscle protein synthesis after resistance training. Yet another recent study compared 2 cups of skim milk as a post workout drink compared to a soy drink and a “sports drink.”

In this study, the milk and soy drinks were matched for basic macronutrient ratios and calories and all three were matched for total calories. 56 male volunteers were split into three groups, with all put on a resistance training program for 12 weeks. The volunteers were then randomly assigned one of the three drinks to consume as a post workout drink and again one hour after the workouts.

Although no major differences were found in strength between the 3 groups, the group getting the milk had the greatest increase in muscle mass (via increases in Type I and II fibers) with researchers concluding “…chronic post exercise consumption of milk promotes greater hypertrophy during the early stages of resistance training in novice weightlifters when compared with isoenergetic soy or carbohydrate consumption.”

But it gets better: how about our favorite childhood drink, chocolate milk? How about chocolate milk vs. two commercial energy/fluid replacement drinks, such as Gatorade and Endurox R4?

One recent study—albeit a small one—found chocolate milk as effective as Gatorade, and more effective than Endurox, as a recovery drink for trained cyclists between exhaustive bouts of endurance exercise.

Now is this a condemnation of sports drinks and an endorsement for milk/chocolate milk as the last word on post-workout drinks? Not at all: remember those essential questions I mentioned above? You have to look at such a study in context—in other words, at the experimental design and how that applies to the “real world.” The subjects fasted for 10 - 12 h prior to the chocolate milk experiment, and these drinks were the only food these guys had for 14 - 16 hours. The results may have been quite different had they been following their normal eating patterns.

They also measured effects on endurance vs.—say—strength or increased protein synthesis, etc.

So, in the context of this particular study design, look at it this way: chocolate milk has casein (a “slow” protein), and whey (a “fast” protein) as well as calcium, some vitamins and a bunch of carbohydrates—so it makes a pretty good, cheap MRP, if that’s all you are going to get all day long. It’s not a half-bad post-workout drink either. It’s not the best MRP—or post workout drink—I could design, but it’s cheap and easy to find. The reality is that there are some inexpensive foods out there can be used, and most of your old school bodybuilders and strong men used milk as the original post workout drink/MRP.

The study that looked at milk vs. soy and sports drink, was done in novice weight lifters, so that too needs to be taken into consideration. Regardless, milk, in particular chocolate milk, should make a perfectly acceptable and inexpensive post workout drink and people who think it’s too “old school” or not “high tech” enough to be if any use are clearly misinformed and the victim of marketing.

Now the study we need to see that does not exist, of course, is milk or chocolate milk vs. a well thought out post-workout drink of—say—whey and maltodextrin (high GI carb source), in experienced weight lifters who are not fasted—but don’t hold your breath on that one. Studies like that get expensive quickly and also pose practical issues. For example, if you wanted to match the protein content of—say—2 scoops of whey isolate to chocolate milk (so the groups were getting an equivalent amount of protein), the subjects would need to drink a large volume of milk (remember, milk is mostly water).

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