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The Top 10 Post Workout Nutrition Myths
by Dave Barr
The Revolution has come, are you ready?
The world of strength training is obviously full of contradiction and confusion. Just pick up any standard bodybuilding magazine and you’ll see different people with drastically diverse views, all telling you that they have the one method to help you achieve your goals. But through all of this crap, every now and then we find certain principles that we can take to the grave and apply universally.
Examples include: "lift heavy weights and you’ll get big," "cardio helps with weight loss," and "Canadian men are hung like moose."
Another such principle is the post workout nutrient window, which states that during the time immediately post workout, our bodies are in a state of shock and physical disarray, resulting in an opportunity for enhanced nutrient absorption and accelerated recovery. In fact, it’s pretty safe to say that since its inception a decade ago, this scientifically "proven" idea has revolutionized the way we look at nutrition.
Unfortunately, this principle has become so engrained in our subculture that much of it has mutated and become dogmatic in scope. While the general principles remain, many of the studies on which they are based were done on populations that aren’t completely applicable to us, such as animals or endurance athletes.
Despite the emergence of new, more applicable science, we’ve had a very difficult time in adapting our thinking to these current and better-suited ideas.
Making the situation worse is the fact that everyone seems to have their own input about what post workout nutrition should be! This stems from what I like to call the "telephone-chain effect" (derived from the lesson-yielding children’s game), which illustrates how easily messages can change when passed through a chain of people.
How it works is that one person will dictate something to another, who in turn tells this same information to someone else, who then repeats it to another, and so on. By human nature, each person will subtly alter the message, by leaving out some parts, embellishing others, etc. to the extent that by the time you get to the tenth person, the original statement of "Hey sugar, could you mop up the mess in the pantry with the Swiffer?" becomes warped to something like "Shugart is a messed up panty sniffer."
True as it may be, obviously the point of the latter statement does not even remotely resemble the original.
But since this article is not entitled "The Top Ten Things Wrong With Our Post Workout Information," let’s get to the myths that have developed, and the current reality.
1. Replenishing Glycogen Needs to be a Focus of PWO.
I’m not just suggesting that glycogen resynthesis is not important following exercise, I’m flat out saying that for strength training it’s not even a concern! This is because it’s just really easy to get our glycogen levels back up, and timing is generally not an issue.
Although one study showed that following endurance exercise, glycogen levels were replenished more rapidly when carbohydrates were consumed shortly after the exercise (Ivy, 198, this is really of little concern to most of us. Unless we’re subscribers to Runners World, athletes in competition, or doing 2 a day workouts, why do we care so much about rapid glycogen restoration? After all, we’re mostly concerned with muscle growth, fat loss, and getting stronger.
The most common argument is that the subsequent cellular hydration and swelling will have an anticatabolic effect on muscle. I don’t believe that this is possible because cellular hydration to the extent that we get with creatine supplementation has little effect on muscle protein synthesis or breakdown in healthy men or women (Louis et al., 2003).
Then there’s the suggestion that if we don’t replenish post exercise glycogen right away, we’ll miss a window of opportunity to do so. This is largely hyperbole, exploded from bits and pieces of endurance training studies, and a perfect example of the telephone game effect.
Surprisingly, one study showed that consuming carbohydrates after strength training only increased muscle glycogen by 16% more than when water was consumed (Pascoe et al., 1993)! With this information and the huge amount of carbs that we consume on a daily basis, we should have little doubt that glycogen levels will be maximized within 24 hours of the workout.
Now these may be irrelevant points, because in the effort of keeping our focus where it ought to lie—on maximizing protein synthesis— we’re going to quickly stimulate our glycogen restoration anyway. This is because we consume rapidly absorbed carbohydrates along with our protein and amino acids, which has been shown to enhance muscle protein anabolism (Rasmussen et al., 2000).
In other words, muscle glycogen will be restored whether we make it a priority or not. This way, even those who can’t escape the dogma of having to rapidly restore glycogen get their fix, while at the same time, unknowingly assisting with muscle protein recovery.
2. Pre workout Nutrition will divert blood flow away from muscles during the workout.
One of a plethora of excuses made in an attempt to resist preworkout nutrition; this myth actually makes a lot of sense…until you become familiar with the physiology of hormones. Looking deeper, we can find that the insulin stimulated by food intake, actually enhances blood flow and subsequent nutrient delivery to muscles (Coggins et al., 2001).
Applying this principle, liquid pre workout meal consumption dramatically increases muscle blood flow and protein synthesis (Tipton et al., 2001). This elevation in muscle growth is at least twice that observed with the same drink taken post workout (Tipton et al., 2001)! In fact, this effect even lasts for an hour after the workout, so it’s like having 2 drinks for the price of 1! If you want more detail on this topic check out the article on Arginine blood flow stimulators.
Fortunately, early resistance to this research is falling by the wayside, and people are finally starting to reap the benefits that this practice has to offer. While "pre workout nutrition" just doesn’t sound as sexy as "post workout nutrition," actually doubling our muscle growth should seem pretty #### sexy to everyone!
3. The post workout meal is the most important meal of the day.
I have to admit that with all the hype on post-workout meals over the past few years, I got tangled up in this myth, too. Realistically though, as great as they are, a single post-workout meal will have minimal impact compared to what can happen if your nutrition is completely optimized. Of course it’s heresy to say that these days, but that’s a result of the myth building on itself more than any factual data. For example, as discussed in the myth #2, pre-workout meals can be 200% more effective for stimulating muscle growth compared to post-workout (Tipton et al., 2001).
Perhaps even more important than the pre-workout meal is the old standard: breakfast. No this article isn’t part of a conspiracy by MABB (Mom’s Against Bad Breakfasts) to promote the importance of this meal. Just think about it: being essentially fasted for 8-10 hours is incredibly destructive for muscle -yes even if you eat cottage cheese before bed.
This is especially true in trained individuals like us, because we have higher rates of muscle breakdown (Phillips et al. 2002) The faster we can stop this catabolism once we wake up, the better. In fact, one could even argue that the amount of muscle protein spared from this first meal would be equal to, or even greater, than that gained by a post workout meal.
Also, consuming a high quality slow protein before bed, like Low-Carb Grow! with micellar casein, will largely mitigate the catabolic effect induced by nocturnal fasting. Taking this one step further, nighttime eating will actually put your muscle into anabolic overdrive, by supplying even more amino acids to stimulate this metabolic process.
Finally, a second post workout meal can be even better for protein synthesis than the first, but I’ll get to that one in a bit.
Mini-Summary: Nocturnal feedings, breakfast, preworkout meals, and multiple post workout meals can be more beneficial for muscle growth than a single post workout meal.
4. There’s a one-hour window of opportunity for protein synthesis following a workout.
You may be wondering: is this a myth because the real window is half an hour? Two or 3 hours? Maybe 6 hours? Sadly, in the past 2 weeks I’ve read different articles, all suggesting that the "window" is one of the above lengths of time.
It’s not surprising that with this type of inconsistency that this is probably the most pervasive myth in bodybuilding today! Worse yet, it stems directly from the scientific research itself. The most often cited research on the protein synthetic post workout window, used elderly subjects (Esmark et al., 2001) and cardio exercise findings (Levenhagen et al., 2001) to make their predictions. While this is a completely acceptable practice when these are the only data we have to go on, there are a couple noteworthy problems.
Elderly individuals digest and absorb protein differently than healthy adults. In fact, they digest and absorb whey protein in a similar manner as they do casein (Dangin et al., 2003); in other words they have slow digestion and absorption for whey. Elderly also benefit from having 80% of their daily protein consumed at a single sitting (Arnal et al., 1999), in contrast to the benefits of our multiple feedings.
Additionally, the traditionally referenced Esmark et al. (2001), study showed that consuming the post workout meal just 2 hours after working out actually prevented any improvements induced by the training! Figure that one out and you get a prize.
Secondly, with regards to cardio…well, let’s just say that there’s an obvious difference between how our muscles respond to the two forms of exercise. Bear in mind that with regard to carbohydrate metabolism following a workout, there might not be much of a difference—we just don’t know, but certainly the long-term protein metabolism differences can be seen.
So now what are we supposed to base our nutrition on? Enter the most underrated scientific paper in the last 5 years. Tipton and colleagues (2003) examined responsiveness of protein synthesis for a day after a workout, and found it to reflect a 24 hour enhanced level. That’s right folks, a FULL DAY! This means that having a morning shake will have the same impact on muscle protein synthesis as one consumed following the workout!
These results shouldn’t be too surprising because we’ve known for over a decade that postworkout protein synthesis is jacked up for this long (MacDougall et al., 1995), but if you’re discovering this for the first time, then it’s pretty exciting!
Some research suggests that even 48 hours after the workout our protein synthesis levels can be elevated by ~33% (Phillips et al., 1997), giving us an even longer period during which we can maximize our muscle growth with protein drinks.
Strike one for the one hour post workout window.
5. Consuming the drink immediately following the workout will elicit the greatest protein synthesis.
It’s amazing to see how more advanced, and often experienced, people behave in the gym when it comes to getting their post workout meal. Some guys even sit there, right after their last set, and slug back a drink! In fact I’ve even heard "as soon as the weight hits the floor" touted as the war cry for the hardcore. While this is actually a sub-optimal practice for muscle growth and recovery, not to mention borderline obsessive compulsive, it’s good to see their heart is the right place.
Comparing research that used drinks consumed immediately after a workout (Tipton et al., 2001) versus those ingested an hour after training (Rasmussen et al., 2000), the results are surprising: it seems that post workout meal ingestion actually results in 30% lower protein synthesis rates than when we wait! So every time we thought that we were badass for drinking "as soon as the weight hit the floor, we were actually short changing ourselves. Not a big deal, that’s why we read T-Nation. Let’s just learn, adapt, and move on.
Strike two for the one hour post workout window.
6. The best meal to consume following a post workout meal is a good SOLID meal.
This is where we can start to apply some of the novel information presented above. While we know that our post workout window (is it really even a window any more? 24 hours is more like a giant garage door) lasts for at least 24 hours, we can’t assume that the responses to repeated meals will all be the same.
This is where research by Borsheim and pals (2002) comes in. This landmark research shows that the best thing to consume after our post workout meal is… another protein shake! In fact, if we time it right, we’ll get the same huge increase in protein synthesis. Talk about a double whammy for our muscle growth! Now considering how crazy people get when it comes to a single post workout meal, imagine how they’ll react when you tell them that they can double that effect!
Also, for those who have a hard time accepting the reality explained in myth #5, you’ll get an even bigger response from the second drink, compared to what you get from the first.
7. Insulin sensitivity is enhanced for an hour following a resistance training bout.
The term insulin sensitivity gets thrown around in the strength-training world, as only the most vague of concepts. From here on, lets universally define it as: the inverse of the quantity of insulin required for an effect of a given magnitude. In other words, high insulin sensitivity requires low levels of insulin to do the job. Make sense? Now that we have a working definition, we need to destroy the myth of the one-hour post workout window once and for all!
We know that both endurance exercise and strength training will enhance insulin sensitivity in the long term. This is a good thing. Unfortunately, with all of the hype surrounding the post workout window, people have started throwing out numbers related to how long insulin sensitivity is altered. While we know that heavily damaging eccentric exercise will actually reduce insulin sensitivity (Asp et al., 1996), this should be an extreme condition and not our regular response. So if you’ve overdone it a bit, back off and heal up!
The more common response to strength training is an increase in insulin sensitivity (Fujitani et al., 1998; Miller et al, 1984), and brand new data show even the acute effect from a single bout lasts for over 24 hours (Koopman et al., 2005). So while we’ll have an enhanced whole body insulin sensitivity following resistance training, this effect is even greater for 24 hours following exercise!
Steeerike THREE for the one hour post workout window!
8. Whey is a "fast" protein, ideal for post workout.
Back when it first came out, whey protein was pretty kick ass because it was discovered to be very high quality. Then research came out that made it even more kick ass, because we could classify it as a "fast" digesting protein compared to casein (Boirie et al., 1997).
You know what? This research stands today, because compared to casein, whey protein really is fast! Then again, a tortoise is also fast compared to a snail, but that doesn’t mean we want to take a tortoise to a greyhound park. In other words, we’ve been considering whey a "fast" protein only because we’ve been comparing it to something incredibly slow. When we compare the digestibility of whey to the gold standard of amino acids, on which we base nearly all of our post workout nutritional data, whey flat out sucks.
This is incredibly frustrating because all of the ways to maximize protein synthesis we’ve been discussing have used amino acids. So we need to either use pure amino acids or use something that closely resembles their absorptive properties. This is where whey protein hydrolysate comes in. The protein is already broken up into large peptides, so we get a rapid absorption with peak levels reaching the blood at around 80 minutes (Calbet and MacLean, 2002), compared to 60 minutes for pharmaceutical grade amino acids (Borsheim et al., 2002).
Unfortunately, even the highly touted whey isolate is completely useless for our timing purposes here, because it just takes too long to get taken up by the gut (Dangin et al., 2002). This is all discussed in more detail in the official product review of Surge, complete with graphs of blood amino acid profiles: http://www.t-nation.com/readTopic.do?id=459463
In light of these data and the growing body of literature contradicting the versatility and usefulness of whey protein, it should henceforth be classified as "moderate" or "intermediate" speed protein, with only whey hydrolysate and amino acids existing as truly "fast."
It may be difficult to adjust our thinking, but this is simply more dogma that needs to be destroyed in order to bring us up to date with the proper application of research.
9. Using antioxidants post workout enhances recovery.
Here’s another myth that just makes sense: we work out, cause all kinds of damage to our bodies, then we use antioxidants to help clean up the mess. Simple and sweet. The reality? Neither simple or sweet. In fact, it may not surprise you to find that there is a clear lack of data on antioxidant supplementation following exercise.
Taking a step back to look at the basis for the theory, it’s been shown that damaging eccentric exercise didn’t change the normal levels of our body’s antioxidants (Child et al., 1999). In other words, our body has a natural antioxidant defense capability, and this was not stressed at all despite the exercise and the subsequent muscle damage.
This is contradicted by other data showing that there is an impact of exercise on natural antioxidant levels (Lee et al., 2002; Goldfarb et al., 2005), but clearly the case is not closed. With this conflicting research, you’d have to wonder if antioxidant supplementation would have any effect at all! Oh it does, my oxidized friend, but the effects are not what we’d expect!
Once again, here’s one of the most underrated research papers of the last 5 years—take note folks because this is one of those studies you need to know about. This groundbreaking research by Childs and buddies (2001) examined the impact of post workout antioxidant supplementation on subsequent muscle damage and healing.
You’ll be shocked to know they found that this practice actually increased muscle damage and delayed recovery! That’s right, the microtrauma experienced by the muscle cells was exacerbated by the antioxidants. With this, the greater the damage, the more time it takes to repair.
It seems that there are pro-oxidant effects happening here, meaning that the "antioxidants" actually started causing the damage they were meant to clean up! While this effect is thought to occur with excessive antioxidant use, it’s surprising that these effects were seen at a Vitamin C dosage of ~1100mg and ~900mg N-Acetyl Cysteine per day, for a 200 lb guy, neither of which are all that incredibly high. To my knowledge, this is the only study to investigate antioxidant supplementation after strength training. This makes the findings incredibly powerful because they are directly applicable to us!
On a personal note, I was pretty blown away when I read this paper because I’d been using Vitamin C post workout for years. While these data aren’t strong enough to make me swear off antioxidants altogether, they clearly show that we can overdo it quite easily with these supplements. More importantly, these data help us rethink the post workout window dogma.
10. Aspirin and ibuprofen are good anti-inflammatories for muscle recovery.
The topic of muscle inflammation is pretty hot these days because it’s thought that minimizing this natural response will enhance recovery. By allowing us to hit the gym or get back on the field quicker, we can once again stimulate our bodies with a hard training session.
While the theory holds some water, we need to be careful how far we take it. For example, the use of traditional pain relievers, like aspirin and ibuprofen, has been increasingly common, because most people just don’t like the feeling of muscle soreness (T-Nation readers excepted because we’re hardly "most people"
.
A common effect of these pain relievers is that they exert a powerful anti-inflammatory effect. This fact has excited some budding pseudo-scientists, because they reason that using these common drugs will reduce muscle inflammation and enhance recovery. Great theory, poor applicability.
Early research showed that post workout use of these drugs inhibited our natural production of a chemical necessary for muscle growth and repair (Trappe et al., 2001). Further investigation showed that sure enough, muscle protein synthesis was completely shut down when these drugs were combined with strength training (Trappe et al., 2002). As a final kick in the teeth, using these drugs resulted in no effect on either inflammation (Peterson et al., 2003), or muscle soreness (Trappe et al., 2002).
Essentially we get the worst of all worlds when combining nonsteroidal anti-inflammatory drugs (NSAIDS) like aspirin and ibuprofen, with strength straining. Having said that, it is important to note that there are several different ways of affecting inflammation, some may be good, others are clearly bad. Keep in the back of your mind that limiting inflammation is a good idea, but certainly be aware that it is not universally beneficial.
Ten Take Home Points
—glycogen restoration is all too easy to achieve and may not be as critical as once thought
—protein synthesis needs to be the focus of our recovery intervention
—pre-workout meals actually enhance muscle blood flow and nutrient delivery during exercise
—pre-workout meals, nocturnal feeding, and multiple post workout drinks are more beneficial than a single post workout drink
—the "post workout window" lasts at least 24 hours
—consuming a protein shake immediately after training hinders optimal results
—strength training acutely enhances insulin sensitivity for at least 24 hours
—whey protein is generally only moderate speed, while whey hydrolysate and pure amino acids are "fast"
—antioxidants taken after exercise may increase muscle damage and delay recovery
—aspirin and ibuprofen can prevent the exercise-induced elevation in muscle protein synthesis thus hindering growth and prolonging recovery
Five Frequently Asked Questions
FAQ: If we don’t care about glycogen, then why would we use high glycemic carbs post workout?
A: Don’t forget that the main goal is to maximize protein synthesis, which is likely accomplished using quickly absorbed carbohydrates and greatly elevating insulin.
FAQ: In the study with the pre workout drink, what did they consume and when did they drink it?
A: Pure amino acids and sucrose were consumed immediately before training started.
FAQ: Doesn’t consuming carbs before a workout cause a blood sugar crash during the workout?
A: Usually no, our catecholamine response seems to keep out blood sugar elevated without problems. But if you’re just starting to try this, consume carbs during the workout or have them ready just in case.
FAQ: If there is a 24-hour post workout window, why do we care about consuming multiple drinks?
A: The multiple drink method is still the best way to maximize our anabolic response following training. We take advantage of this "window" by spiking our blood amino acid level as often as we can.
FAQ: If there is a 24-hour post workout window, why do we care about fast or intermediate speed proteins?
A: The multiple drink method can only be used when fast proteins or amino acids are consumed. It just doesn’t work with intermediate speed proteins.
CONCLUSIONS
It’s safe to say that we’ve been brought up to date with the current research regarding strength training and nutrition. Perhaps more importantly it’s clear that the post workout dogma has been destroyed. Unfortunately, with all of this destruction going on, there is a knowledge gap that needs to be filled, which will allow us to apply these new findings.
In other words, we need to figure out what all of this science stuff means, and how we can best use it to our advantage. In an upcoming article, I’ll introduce the Anabolic Index: a detailed blueprint for making use of this latest information, allowing us to maximize our anabolic potential.
Until then, Raise the Barr!
Thanks to: Nathan Devey, Nathan Dewsbury, Tan Huaiyu, Jonathan Boyle, my Phrenologist Dr. Ryan Smith, and everyone who helped review this document.
Dave can be reached via e-mail at [email protected].
References
1. Arnal MA, Mosoni L, Boirie Y, Houlier ML, Morin L, Verdier E, Ritz P, Antoine JM, Prugnaud J, Beaufrere B, Mirand PP. Protein pulse feeding improves protein retention in elderly women. Am J Clin Nutr. 1999 Jun;69(6):1202-8
2. Asp S, Daugaard JR, Kristiansen S, Kiens B, Richter EA. Eccentric exercise decreases maximal insulin action in humans: muscle and systemic effects. J Physiol. 1996 Aug 1;494 ( Pt 3):891-8.
3. Boirie Y, Dangin M, Gachon P, Vasson MP, Maubois JL, Beaufrere B. Slow and fast dietary proteins differently modulate postprandial protein accretion. Proc Natl Acad Sci U S A. 1997 Dec 23;94(26):14930-5.
4. Borsheim E, Tipton KD, Wolf SE, Wolfe RR. Essential amino acids and muscle protein recovery from resistance exercise. Am J Physiol Endocrinol Metab. 2002 Oct;283(4):E648-57.
5. Calbet JA, MacLean DA. Plasma glucagon and insulin responses depend on the rate of appearance of amino acids after ingestion of different protein solutions in humans. J Nutr. 2002 Aug;132(:2174-82.
6. Child R, Brown S, Day S, Donnelly A, Roper H, Saxton J. Changes in indices of antioxidant status, lipid peroxidation and inflammation in human skeletal muscle after eccentric muscle actions. Clin Sci (Lond). 1999 Jan;96(1):105-15.
7. Childs A, Jacobs C, Kaminski T, Halliwell B, Leeuwenburgh C. Supplementation with vitamin C and N-acetyl-cysteine increases oxidative stress in humans after an acute muscle injury induced by eccentric exercise. Free Radic Biol Med. 2001 Sep 15;31(6):745-53.
8. Coggins M, Lindner J, Rattigan S, Jahn L, Fasy E, Kaul S, Barrett E. Physiologic hyperinsulinemia enhances human skeletal muscle perfusion by capillary recruitment. Diabetes. 2001 Dec;50(12):2682-90.
9. Dangin M, Boirie Y, Garcia-Rodenas C, Gachon P, Fauquant J, Callier P, Ballevre O, Beaufrere B. The digestion rate of protein is an independent regulating factor of postprandial protein retention Am J Physiol Endocrinol Metab 280: E340-E348, 2001
10. Dangin M, Guillet C, Garcia-Rodenas C, Gachon P, Bouteloup-Demange C, Reiffers-Magnani K, Fauquant J, Ballevre O, Beaufrere B. The rate of protein digestion affects protein gain differently during aging in humans. Physiol. 2003 Jun 1;549(Pt 2):635-44.
11. Esmarck B, Andersen JL, Olsen S, Richter EA, Mizuno M, Kjaer M. Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans. J Physiol. 2001 Aug 15;535(Pt 1):301-11.
12. Fujitani J, Higaki Y, Kagawa T, Sakamoto M, Kiyonaga A, Shindo M,
Taniguchi A, Nakai Y, Tokuyama K, Tanaka H. Intravenous glucose tolerance test-derived glucose effectiveness in strength-trained humans. Metabolism. 1998 Jul;47(7):874-7.
13. Goldfarb AH, Bloomer RJ, McKenzie MJ. Combined antioxidant treatment effects on blood oxidative stress after eccentric exercise. Med Sci Sports Exerc. 2005 Feb;37(2):234-9.
14. Ivy JL, Katz AL, Cutler CL, Sherman WM, Coyle EF. Muscle glycogen synthesis after exercise: effect of time of carbohydrate ingestion. J Appl Physiol. 1988 Apr;64(4):1480-5.
15. Koopman R, Manders RJ, Zorenc AH, Hul GB, Kuipers H, Keizer HA, van Loon LJ. A single session of resistance exercise enhances insulin sensitivity for at least 24 h in healthy men. Eur J Appl Physiol. 2005 May;94(1-2):180-7.
16. Lee J, Goldfarb AH, Rescino MH, Hegde S, Patrick S, Apperson K. Eccentric exercise effect on blood oxidative-stress markers and delayed onset of muscle soreness. Med Sci Sports Exerc. 2002 Mar;34(3):443-8.
17. Levenhagen DK, Gresham JD, Carlson MG, Maron DJ, Borel MJ, Flakoll PJ. Postexercise nutrient intake timing in humans is critical to recovery of leg glucose and protein homeostasis. Am J Physiol Endocrinol Metab. 2001 Jun;280(6):E982-93.
18. Louis M, Poortmans JR, Francaux M, Berre J, Boisseau N, Brassine E, Cuthbertson DJ, Smith K, Babraj JA, Waddell T, Rennie MJ. No effect of creatine supplementation on human myofibrillar and sarcoplasmic protein synthesis after resistance exercise. Am J Physiol Endocrinol Metab. 2003 Nov;285(5):E1089-94.
19. MacDougall JD, Gibala MJ, Tarnopolsky MA, MacDonald JR, Interisano SA, Yarasheski KE. The time course for elevated muscle protein synthesis following heavy resistance exercise. Can J Appl Physiol. 1995 Dec;20(4):480-6.
20. Miller WJ, Sherman WM, Ivy JL. Effect of strength training on glucose tolerance and post-glucose insulin response. Med Sci Sports Exerc. 1984 Dec;16(6):539-43.
21. Pascoe DD, Costill DL, Fink WJ, Robergs RA, Zachwieja JJ. Glycogen resynthesis in skeletal muscle following resistive exercise. Med Sci Sports Exerc. 1993 Mar;25(3):349-54.
22. Peterson JM, Trappe TA, Mylona E, White F, Lambert CP, Evans WJ, Pizza FX. Ibuprofen and acetaminophen: effect on muscle inflammation after eccentric exercise. Med Sci Sports Exerc. 2003 Jun;35(6):892-6.
23. Phillips SM, Tipton KD, Aarsland A, Wolf SE, Wolfe RR. Mixed muscle protein synthesis and breakdown after resistance exercise in humans. Am J Physiol. 1997 Jul;273(1 Pt 1):E99-107.
24. Phillips SM, Parise G, Roy BD, Tipton KD, Wolfe RR, Tamopolsky MA.
Resistance-training-induced adaptations in skeletal muscle protein turnover in the fed state. Can J Physiol Pharmacol. 2002 Nov;80(11):1045-53.
25. Rasmussen, BB, Tipton KD, Miller SL, Wolf SE, and Wolfe RR. An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise. J Appl Physiol 88: 386-392, 2000
26. Tipton KD, Rasmussen BB, Miller SL, Wolf SE, Owens-Stovall SK, Petrini BE, Wolfe RR. Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. Am J Physiol Endocrinol Metab. 2001 Aug;281(2):E197-206
27. Tipton KD, Borsheim E, Wolf SE, Sanford AP, Wolfe RR. Acute response of net muscle protein balance reflects 24-h balance after exercise and amino acid ingestion. Am J Physiol Endocrinol Metab. 2003 Jan;284(1):E76-89.
28. Trappe TA, Fluckey JD, White F, Lambert CP, Evans WJ. Skeletal muscle PGF(2)(alpha) and PGE(2) in response to eccentric resistance exercise: influence of ibuprofen acetaminophen. J Clin Endocrinol Metab. 2001 Oct;86(10):5067-70.
29. Trappe TA, White F, Lambert CP, Cesar D, Hellerstein M, Evans WJ.
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stukje tekst;
(misschien handig om er een sticky van te maken, aangezien ik hier geen permissie voor had
)The Top 10 Post Workout Nutrition Myths
by Dave Barr
The Revolution has come, are you ready?
The world of strength training is obviously full of contradiction and confusion. Just pick up any standard bodybuilding magazine and you’ll see different people with drastically diverse views, all telling you that they have the one method to help you achieve your goals. But through all of this crap, every now and then we find certain principles that we can take to the grave and apply universally.
Examples include: "lift heavy weights and you’ll get big," "cardio helps with weight loss," and "Canadian men are hung like moose."
Another such principle is the post workout nutrient window, which states that during the time immediately post workout, our bodies are in a state of shock and physical disarray, resulting in an opportunity for enhanced nutrient absorption and accelerated recovery. In fact, it’s pretty safe to say that since its inception a decade ago, this scientifically "proven" idea has revolutionized the way we look at nutrition.
Unfortunately, this principle has become so engrained in our subculture that much of it has mutated and become dogmatic in scope. While the general principles remain, many of the studies on which they are based were done on populations that aren’t completely applicable to us, such as animals or endurance athletes.
Despite the emergence of new, more applicable science, we’ve had a very difficult time in adapting our thinking to these current and better-suited ideas.
Making the situation worse is the fact that everyone seems to have their own input about what post workout nutrition should be! This stems from what I like to call the "telephone-chain effect" (derived from the lesson-yielding children’s game), which illustrates how easily messages can change when passed through a chain of people.
How it works is that one person will dictate something to another, who in turn tells this same information to someone else, who then repeats it to another, and so on. By human nature, each person will subtly alter the message, by leaving out some parts, embellishing others, etc. to the extent that by the time you get to the tenth person, the original statement of "Hey sugar, could you mop up the mess in the pantry with the Swiffer?" becomes warped to something like "Shugart is a messed up panty sniffer."
True as it may be, obviously the point of the latter statement does not even remotely resemble the original.
But since this article is not entitled "The Top Ten Things Wrong With Our Post Workout Information," let’s get to the myths that have developed, and the current reality.
1. Replenishing Glycogen Needs to be a Focus of PWO.
I’m not just suggesting that glycogen resynthesis is not important following exercise, I’m flat out saying that for strength training it’s not even a concern! This is because it’s just really easy to get our glycogen levels back up, and timing is generally not an issue.
Although one study showed that following endurance exercise, glycogen levels were replenished more rapidly when carbohydrates were consumed shortly after the exercise (Ivy, 198, this is really of little concern to most of us. Unless we’re subscribers to Runners World, athletes in competition, or doing 2 a day workouts, why do we care so much about rapid glycogen restoration? After all, we’re mostly concerned with muscle growth, fat loss, and getting stronger.
The most common argument is that the subsequent cellular hydration and swelling will have an anticatabolic effect on muscle. I don’t believe that this is possible because cellular hydration to the extent that we get with creatine supplementation has little effect on muscle protein synthesis or breakdown in healthy men or women (Louis et al., 2003).
Then there’s the suggestion that if we don’t replenish post exercise glycogen right away, we’ll miss a window of opportunity to do so. This is largely hyperbole, exploded from bits and pieces of endurance training studies, and a perfect example of the telephone game effect.
Surprisingly, one study showed that consuming carbohydrates after strength training only increased muscle glycogen by 16% more than when water was consumed (Pascoe et al., 1993)! With this information and the huge amount of carbs that we consume on a daily basis, we should have little doubt that glycogen levels will be maximized within 24 hours of the workout.
Now these may be irrelevant points, because in the effort of keeping our focus where it ought to lie—on maximizing protein synthesis— we’re going to quickly stimulate our glycogen restoration anyway. This is because we consume rapidly absorbed carbohydrates along with our protein and amino acids, which has been shown to enhance muscle protein anabolism (Rasmussen et al., 2000).
In other words, muscle glycogen will be restored whether we make it a priority or not. This way, even those who can’t escape the dogma of having to rapidly restore glycogen get their fix, while at the same time, unknowingly assisting with muscle protein recovery.
2. Pre workout Nutrition will divert blood flow away from muscles during the workout.
One of a plethora of excuses made in an attempt to resist preworkout nutrition; this myth actually makes a lot of sense…until you become familiar with the physiology of hormones. Looking deeper, we can find that the insulin stimulated by food intake, actually enhances blood flow and subsequent nutrient delivery to muscles (Coggins et al., 2001).
Applying this principle, liquid pre workout meal consumption dramatically increases muscle blood flow and protein synthesis (Tipton et al., 2001). This elevation in muscle growth is at least twice that observed with the same drink taken post workout (Tipton et al., 2001)! In fact, this effect even lasts for an hour after the workout, so it’s like having 2 drinks for the price of 1! If you want more detail on this topic check out the article on Arginine blood flow stimulators.
Fortunately, early resistance to this research is falling by the wayside, and people are finally starting to reap the benefits that this practice has to offer. While "pre workout nutrition" just doesn’t sound as sexy as "post workout nutrition," actually doubling our muscle growth should seem pretty #### sexy to everyone!
3. The post workout meal is the most important meal of the day.
I have to admit that with all the hype on post-workout meals over the past few years, I got tangled up in this myth, too. Realistically though, as great as they are, a single post-workout meal will have minimal impact compared to what can happen if your nutrition is completely optimized. Of course it’s heresy to say that these days, but that’s a result of the myth building on itself more than any factual data. For example, as discussed in the myth #2, pre-workout meals can be 200% more effective for stimulating muscle growth compared to post-workout (Tipton et al., 2001).
Perhaps even more important than the pre-workout meal is the old standard: breakfast. No this article isn’t part of a conspiracy by MABB (Mom’s Against Bad Breakfasts) to promote the importance of this meal. Just think about it: being essentially fasted for 8-10 hours is incredibly destructive for muscle -yes even if you eat cottage cheese before bed.
This is especially true in trained individuals like us, because we have higher rates of muscle breakdown (Phillips et al. 2002) The faster we can stop this catabolism once we wake up, the better. In fact, one could even argue that the amount of muscle protein spared from this first meal would be equal to, or even greater, than that gained by a post workout meal.
Also, consuming a high quality slow protein before bed, like Low-Carb Grow! with micellar casein, will largely mitigate the catabolic effect induced by nocturnal fasting. Taking this one step further, nighttime eating will actually put your muscle into anabolic overdrive, by supplying even more amino acids to stimulate this metabolic process.
Finally, a second post workout meal can be even better for protein synthesis than the first, but I’ll get to that one in a bit.
Mini-Summary: Nocturnal feedings, breakfast, preworkout meals, and multiple post workout meals can be more beneficial for muscle growth than a single post workout meal.
4. There’s a one-hour window of opportunity for protein synthesis following a workout.
You may be wondering: is this a myth because the real window is half an hour? Two or 3 hours? Maybe 6 hours? Sadly, in the past 2 weeks I’ve read different articles, all suggesting that the "window" is one of the above lengths of time.
It’s not surprising that with this type of inconsistency that this is probably the most pervasive myth in bodybuilding today! Worse yet, it stems directly from the scientific research itself. The most often cited research on the protein synthetic post workout window, used elderly subjects (Esmark et al., 2001) and cardio exercise findings (Levenhagen et al., 2001) to make their predictions. While this is a completely acceptable practice when these are the only data we have to go on, there are a couple noteworthy problems.
Elderly individuals digest and absorb protein differently than healthy adults. In fact, they digest and absorb whey protein in a similar manner as they do casein (Dangin et al., 2003); in other words they have slow digestion and absorption for whey. Elderly also benefit from having 80% of their daily protein consumed at a single sitting (Arnal et al., 1999), in contrast to the benefits of our multiple feedings.
Additionally, the traditionally referenced Esmark et al. (2001), study showed that consuming the post workout meal just 2 hours after working out actually prevented any improvements induced by the training! Figure that one out and you get a prize.
Secondly, with regards to cardio…well, let’s just say that there’s an obvious difference between how our muscles respond to the two forms of exercise. Bear in mind that with regard to carbohydrate metabolism following a workout, there might not be much of a difference—we just don’t know, but certainly the long-term protein metabolism differences can be seen.
So now what are we supposed to base our nutrition on? Enter the most underrated scientific paper in the last 5 years. Tipton and colleagues (2003) examined responsiveness of protein synthesis for a day after a workout, and found it to reflect a 24 hour enhanced level. That’s right folks, a FULL DAY! This means that having a morning shake will have the same impact on muscle protein synthesis as one consumed following the workout!
These results shouldn’t be too surprising because we’ve known for over a decade that postworkout protein synthesis is jacked up for this long (MacDougall et al., 1995), but if you’re discovering this for the first time, then it’s pretty exciting!
Some research suggests that even 48 hours after the workout our protein synthesis levels can be elevated by ~33% (Phillips et al., 1997), giving us an even longer period during which we can maximize our muscle growth with protein drinks.
Strike one for the one hour post workout window.
5. Consuming the drink immediately following the workout will elicit the greatest protein synthesis.
It’s amazing to see how more advanced, and often experienced, people behave in the gym when it comes to getting their post workout meal. Some guys even sit there, right after their last set, and slug back a drink! In fact I’ve even heard "as soon as the weight hits the floor" touted as the war cry for the hardcore. While this is actually a sub-optimal practice for muscle growth and recovery, not to mention borderline obsessive compulsive, it’s good to see their heart is the right place.
Comparing research that used drinks consumed immediately after a workout (Tipton et al., 2001) versus those ingested an hour after training (Rasmussen et al., 2000), the results are surprising: it seems that post workout meal ingestion actually results in 30% lower protein synthesis rates than when we wait! So every time we thought that we were badass for drinking "as soon as the weight hit the floor, we were actually short changing ourselves. Not a big deal, that’s why we read T-Nation. Let’s just learn, adapt, and move on.
Strike two for the one hour post workout window.
6. The best meal to consume following a post workout meal is a good SOLID meal.
This is where we can start to apply some of the novel information presented above. While we know that our post workout window (is it really even a window any more? 24 hours is more like a giant garage door) lasts for at least 24 hours, we can’t assume that the responses to repeated meals will all be the same.
This is where research by Borsheim and pals (2002) comes in. This landmark research shows that the best thing to consume after our post workout meal is… another protein shake! In fact, if we time it right, we’ll get the same huge increase in protein synthesis. Talk about a double whammy for our muscle growth! Now considering how crazy people get when it comes to a single post workout meal, imagine how they’ll react when you tell them that they can double that effect!
Also, for those who have a hard time accepting the reality explained in myth #5, you’ll get an even bigger response from the second drink, compared to what you get from the first.
7. Insulin sensitivity is enhanced for an hour following a resistance training bout.
The term insulin sensitivity gets thrown around in the strength-training world, as only the most vague of concepts. From here on, lets universally define it as: the inverse of the quantity of insulin required for an effect of a given magnitude. In other words, high insulin sensitivity requires low levels of insulin to do the job. Make sense? Now that we have a working definition, we need to destroy the myth of the one-hour post workout window once and for all!
We know that both endurance exercise and strength training will enhance insulin sensitivity in the long term. This is a good thing. Unfortunately, with all of the hype surrounding the post workout window, people have started throwing out numbers related to how long insulin sensitivity is altered. While we know that heavily damaging eccentric exercise will actually reduce insulin sensitivity (Asp et al., 1996), this should be an extreme condition and not our regular response. So if you’ve overdone it a bit, back off and heal up!
The more common response to strength training is an increase in insulin sensitivity (Fujitani et al., 1998; Miller et al, 1984), and brand new data show even the acute effect from a single bout lasts for over 24 hours (Koopman et al., 2005). So while we’ll have an enhanced whole body insulin sensitivity following resistance training, this effect is even greater for 24 hours following exercise!
Steeerike THREE for the one hour post workout window!
8. Whey is a "fast" protein, ideal for post workout.
Back when it first came out, whey protein was pretty kick ass because it was discovered to be very high quality. Then research came out that made it even more kick ass, because we could classify it as a "fast" digesting protein compared to casein (Boirie et al., 1997).
You know what? This research stands today, because compared to casein, whey protein really is fast! Then again, a tortoise is also fast compared to a snail, but that doesn’t mean we want to take a tortoise to a greyhound park. In other words, we’ve been considering whey a "fast" protein only because we’ve been comparing it to something incredibly slow. When we compare the digestibility of whey to the gold standard of amino acids, on which we base nearly all of our post workout nutritional data, whey flat out sucks.
This is incredibly frustrating because all of the ways to maximize protein synthesis we’ve been discussing have used amino acids. So we need to either use pure amino acids or use something that closely resembles their absorptive properties. This is where whey protein hydrolysate comes in. The protein is already broken up into large peptides, so we get a rapid absorption with peak levels reaching the blood at around 80 minutes (Calbet and MacLean, 2002), compared to 60 minutes for pharmaceutical grade amino acids (Borsheim et al., 2002).
Unfortunately, even the highly touted whey isolate is completely useless for our timing purposes here, because it just takes too long to get taken up by the gut (Dangin et al., 2002). This is all discussed in more detail in the official product review of Surge, complete with graphs of blood amino acid profiles: http://www.t-nation.com/readTopic.do?id=459463
In light of these data and the growing body of literature contradicting the versatility and usefulness of whey protein, it should henceforth be classified as "moderate" or "intermediate" speed protein, with only whey hydrolysate and amino acids existing as truly "fast."
It may be difficult to adjust our thinking, but this is simply more dogma that needs to be destroyed in order to bring us up to date with the proper application of research.
9. Using antioxidants post workout enhances recovery.
Here’s another myth that just makes sense: we work out, cause all kinds of damage to our bodies, then we use antioxidants to help clean up the mess. Simple and sweet. The reality? Neither simple or sweet. In fact, it may not surprise you to find that there is a clear lack of data on antioxidant supplementation following exercise.
Taking a step back to look at the basis for the theory, it’s been shown that damaging eccentric exercise didn’t change the normal levels of our body’s antioxidants (Child et al., 1999). In other words, our body has a natural antioxidant defense capability, and this was not stressed at all despite the exercise and the subsequent muscle damage.
This is contradicted by other data showing that there is an impact of exercise on natural antioxidant levels (Lee et al., 2002; Goldfarb et al., 2005), but clearly the case is not closed. With this conflicting research, you’d have to wonder if antioxidant supplementation would have any effect at all! Oh it does, my oxidized friend, but the effects are not what we’d expect!
Once again, here’s one of the most underrated research papers of the last 5 years—take note folks because this is one of those studies you need to know about. This groundbreaking research by Childs and buddies (2001) examined the impact of post workout antioxidant supplementation on subsequent muscle damage and healing.
You’ll be shocked to know they found that this practice actually increased muscle damage and delayed recovery! That’s right, the microtrauma experienced by the muscle cells was exacerbated by the antioxidants. With this, the greater the damage, the more time it takes to repair.
It seems that there are pro-oxidant effects happening here, meaning that the "antioxidants" actually started causing the damage they were meant to clean up! While this effect is thought to occur with excessive antioxidant use, it’s surprising that these effects were seen at a Vitamin C dosage of ~1100mg and ~900mg N-Acetyl Cysteine per day, for a 200 lb guy, neither of which are all that incredibly high. To my knowledge, this is the only study to investigate antioxidant supplementation after strength training. This makes the findings incredibly powerful because they are directly applicable to us!
On a personal note, I was pretty blown away when I read this paper because I’d been using Vitamin C post workout for years. While these data aren’t strong enough to make me swear off antioxidants altogether, they clearly show that we can overdo it quite easily with these supplements. More importantly, these data help us rethink the post workout window dogma.
10. Aspirin and ibuprofen are good anti-inflammatories for muscle recovery.
The topic of muscle inflammation is pretty hot these days because it’s thought that minimizing this natural response will enhance recovery. By allowing us to hit the gym or get back on the field quicker, we can once again stimulate our bodies with a hard training session.
While the theory holds some water, we need to be careful how far we take it. For example, the use of traditional pain relievers, like aspirin and ibuprofen, has been increasingly common, because most people just don’t like the feeling of muscle soreness (T-Nation readers excepted because we’re hardly "most people"
. A common effect of these pain relievers is that they exert a powerful anti-inflammatory effect. This fact has excited some budding pseudo-scientists, because they reason that using these common drugs will reduce muscle inflammation and enhance recovery. Great theory, poor applicability.
Early research showed that post workout use of these drugs inhibited our natural production of a chemical necessary for muscle growth and repair (Trappe et al., 2001). Further investigation showed that sure enough, muscle protein synthesis was completely shut down when these drugs were combined with strength training (Trappe et al., 2002). As a final kick in the teeth, using these drugs resulted in no effect on either inflammation (Peterson et al., 2003), or muscle soreness (Trappe et al., 2002).
Essentially we get the worst of all worlds when combining nonsteroidal anti-inflammatory drugs (NSAIDS) like aspirin and ibuprofen, with strength straining. Having said that, it is important to note that there are several different ways of affecting inflammation, some may be good, others are clearly bad. Keep in the back of your mind that limiting inflammation is a good idea, but certainly be aware that it is not universally beneficial.
Ten Take Home Points
—glycogen restoration is all too easy to achieve and may not be as critical as once thought
—protein synthesis needs to be the focus of our recovery intervention
—pre-workout meals actually enhance muscle blood flow and nutrient delivery during exercise
—pre-workout meals, nocturnal feeding, and multiple post workout drinks are more beneficial than a single post workout drink
—the "post workout window" lasts at least 24 hours
—consuming a protein shake immediately after training hinders optimal results
—strength training acutely enhances insulin sensitivity for at least 24 hours
—whey protein is generally only moderate speed, while whey hydrolysate and pure amino acids are "fast"
—antioxidants taken after exercise may increase muscle damage and delay recovery
—aspirin and ibuprofen can prevent the exercise-induced elevation in muscle protein synthesis thus hindering growth and prolonging recovery
Five Frequently Asked Questions
FAQ: If we don’t care about glycogen, then why would we use high glycemic carbs post workout?
A: Don’t forget that the main goal is to maximize protein synthesis, which is likely accomplished using quickly absorbed carbohydrates and greatly elevating insulin.
FAQ: In the study with the pre workout drink, what did they consume and when did they drink it?
A: Pure amino acids and sucrose were consumed immediately before training started.
FAQ: Doesn’t consuming carbs before a workout cause a blood sugar crash during the workout?
A: Usually no, our catecholamine response seems to keep out blood sugar elevated without problems. But if you’re just starting to try this, consume carbs during the workout or have them ready just in case.
FAQ: If there is a 24-hour post workout window, why do we care about consuming multiple drinks?
A: The multiple drink method is still the best way to maximize our anabolic response following training. We take advantage of this "window" by spiking our blood amino acid level as often as we can.
FAQ: If there is a 24-hour post workout window, why do we care about fast or intermediate speed proteins?
A: The multiple drink method can only be used when fast proteins or amino acids are consumed. It just doesn’t work with intermediate speed proteins.
CONCLUSIONS
It’s safe to say that we’ve been brought up to date with the current research regarding strength training and nutrition. Perhaps more importantly it’s clear that the post workout dogma has been destroyed. Unfortunately, with all of this destruction going on, there is a knowledge gap that needs to be filled, which will allow us to apply these new findings.
In other words, we need to figure out what all of this science stuff means, and how we can best use it to our advantage. In an upcoming article, I’ll introduce the Anabolic Index: a detailed blueprint for making use of this latest information, allowing us to maximize our anabolic potential.
Until then, Raise the Barr!
Thanks to: Nathan Devey, Nathan Dewsbury, Tan Huaiyu, Jonathan Boyle, my Phrenologist Dr. Ryan Smith, and everyone who helped review this document.
Dave can be reached via e-mail at [email protected].
References
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