Solving the Post Workout Puzzle
By Dr. John M Berardi, Ph.D.
The Unlikely Scientist
When I first began pushing iron, I knew very little about the science of weight training and nutrition. And to be honest, I really didn't care much about the science part. You see, I was 18 years old. At that age, all I personally cared about was being big, strong, and intimidating. Oh, and I'd better not forget to mention that I also cared a lot about sex. Somehow I figured that the pursuit of raw, intimidating "manliness" would ultimately equate to getting chicks. So most of my mental reserves were directed at getting really big and kicking everyone's ass both in and out of the gym.
Since my brain was pretty much occupied with all those deep philosophical musings, you can probably imagine that there wasn't much room in my melon for scientific thought. That was compounded with the fact that my predominant science experiences had been with Mr. Richard Wack, the very nerdy, defeated high-school chemistry teacher that had us mixing oil and water to illustrate chemical bonding or lack thereof (I swear that was his name!).
At the time, as ignorant as I was to science, there were a few scientifically validated nuggets of wisdom floating around the local gym. Sure, if I'd have known they were "science," I probably would have ignored them entirely. But since these pieces of science were cleverly disguised and because all the big guys were talking about them, I tried to use this information to it's fullest.
We discussed the merits of statements like "eating a lot of extra protein will make you grow" and "sleeping 8 hours a night will help you recover." These statements seemed to be entirely true and backed up by countless gym experiences. Today, they also happen to be backed up by well-controlled, university studies.
One statement that I was always quite fond of was the one that told me that there was a 90-minute "window of opportunity" after training in which I could eat tons of protein and carbohydrates. Since I love eating protein and carbs, I loved that particular gym "fact." And not only was it cool that it allowed me to pig out on protein and carbs after my workouts, it was equally exciting that in doing so, I would be recovering from my workout and packing on muscle mass at an alarming rate. "Who needs science?" I'd ask, "I'm gonna go eat!"
Unfortunately, somewhere along the way, this crucial piece of post-workout wisdom has been lost. As a result, few modern trainees have even heard of the "window of opportunity" concept. Some guys today just think that eating "a little something" is enough. To go even further, some even have the audacity to fast for hours after workouts in order to "burn more fat" or to "enhance their GH response." It frightens me that these new practices are almost becoming as popular as the old window I was so fond of taking full advantage of. But I'm here to do something about it!
Despite the anti-science beginnings I discussed earlier, you may be amazed to know my current profession involves scientific research. In fact, I sit here typing this article surrounded by nothing other than science textbooks and journals. It constitutes some of the literature that I've read along the way to a PhD program in exercise and nutritional biochemistry. Who would of thunk it? Armed with all this science, my plan is to unscramble the post-workout puzzle that has lead so many trainees astray.
Post-Workout 101
Over the last few years, I've spent quite a bit of time trying to unscramble the post-workout puzzle in my own mind. And as a result of my research, I've discovered that immediately after a single bout of exercise, three main physiological events must be manipulated for enhanced recovery. These changes can only be described as "destructive" in terms of both training performance and muscle protein balance.
Before I go on, I want you to keep in mind that by exercise I mean either strength and power training or endurance training. Unfortunately, no trainee is immune to the three post-exercise phenomena. These three factors are as follows:
1. Glycogen Stores are low
2. Protein Breakdown is increased
3. Muscle Protein Balance is negative
It should be noted here that in addition to the above that Protein Synthesis also goes down after an endurance training session. And Protein Synthesis either goes up or remains unchanged after a strength training session. But either way, Protein Breakdown still predominates.
For those not well versed in physiological jargon, here's a little explanation of each:
Glycogen is muscle energy. Low glycogen stores mean that there's less cellular energy for daily life and certainly less energy for subsequent workouts. In this situation, training and performance suffer.
Protein Breakdown indicates that body tissues (which are made of protein) are being degraded. Increases in protein breakdown can lead to losses of muscle mass.
Muscle Protein Balance is regulated by the balance between Protein Synthesis and Protein Breakdown in the following way:
Muscle Protein Balance = Protein Synthesis - Protein Breakdown
Immediately after an endurance workout, protein synthesis (building) goes down and protein breakdown goes up. This leads to a negative Muscle Protein Balance and a loss of muscle.
And immediately after a strength workout, protein building either stays the same or slightly goes up but protein breakdown goes way up. This also leads to a negative Muscle Protein Balance and a loss of muscle.
As a result of these three post workout phenomena, a failure to rapidly bring the body back into recovery mode (i.e., to increase glycogen stores, to increase protein synthesis, and to prevent protein breakdown), has severeal potential consequences:
1. Prolonged muscle soreness and fatigue.
2. Poor subsequent performances on the track, field, and/or in the gym.
3. Symptoms of and or full-flegged staleness and overtraining.
4. Minimal gains in muscle mass despite a well-designed training program.
5. Losses of muscle mass and a secondary lowering of metabolic rate can occur if volume and intensity get high enough
"But wait just a minute!" you shout. "I thought exercise was supposed to increase performance, metabolic rate, and muscle mass! Now you're telling me that it could do just the opposite." Slow down, tiger. Let me explain.
It's interesting and very telling to look at the time course of changes in protein and glycogen balance after a workout. Back in 1995, researchers showed that immediately after strength training, protein balance is negative (indicating muscle loss) due to the big increase in protein breakdown and the marginal increase in protein synthesis (1).
Furthermore, this situation seemed to persist for a few hours after the workout. But a few hours later, an interesting switch occurred. Protein synthesis started to climb and breakdown started to fall (although it was still elevated).
This ultimately (about 24 hours later) can lead to a muscle protein balance where synthesis is equal to breakdown (no gain or loss in mass), or a positive protein balance where synthesis is greater than protein breakdown (voila, muscle gains).
So, even if you do everything wrong after hitting the iron, it's only the first few hours after the workout that are extremely catabolic. Twenty-four hours later, though, the body has normalized itself and is either neutral or slightly anabolic. So it appears that under normal circumstances, we've got to lose a little muscle to gain a little muscle.
I'm here to tell you, however, that if you manage the post-workout period correctly, you don't have to lose any muscle. And not only that, if you know how, you can actually achieve and maintain a positive protein balance throughout the entire recovery process. We'll talk more about this later on.
Unfortunately for our endurance friends, the prognosis isn't as good as it is for the muscle bound. Immediately after an endurance-training bout, muscle protein balance is very negative because there's both a big increase in protein breakdown and a big decrease in protein synthesis.
This situation, however, isn't as quickly reversible as it is in our muscle heads. In these athletes there remains a large negative protein balance for 8 hours or more after endurance exercise (2). Uh, say goodbye to the muscle!
Please keep in mind that these exercise studies were done with a day of rest following the training and measurement period. And most importantly, they were done without proper post-workout nutrition!
So, what about the athletes who are training every day (and up to two times or more per day) and then screw up on the post-workout nutrition? One can only speculate that they'll suffer from a big negative muscle protein balance. Since they're training time and time again before protein balance has been brought back to normal, they'll nearly always be in a state of protein breakdown. Bye-bye muscle, metabolism, and training intensity!
With this explained, I'd like to get back to the original objection. I believe that since the average trainee isn't training with the high frequency and intensity that could lead to large and persistent losses in muscle mass and metabolic rate, he or she has very little to worry about in terms of losses of muscle mass and metabolic rate.
With that said, however, the first four problems listed above (soreness, poor performance, overtraining, and stagnation) are often very much a reality for the average athlete and their valiant gym efforts could become frustrating and seem fruitless. Optimal post-workout nutrition can play heavily into the avoidance of the problems discussed above.
Competitive athletes, on the other hand, are particularly vulnerable to all of the above scenarios (including losses in mass and metabolic rate). Due to their training frequency, lack of time off, and intense work rates, most athletes are walking a fine line between their optimal training zone and overtraining. This is one of the reasons why they're subject to all types of ailments during their seasons.
The competitive athlete frequently has to suffer through excessive fatigue yet an inability to sleep at night, chronic muscle soreness, gastrointestinal and appetite alterations, irritability, loss of sex drive, and frequent infections and flu-like symptoms, just to name a few.
While overtraining in these athletes is brought on by a complex interaction between many factors, nutrition is one factor that is so easy to manage. Any competitive athlete would be foolish to ignore it as they wage war against the dreaded adversary - overtraining.
Back to Recovery Mode
At this point, if I've accomplished my mission, you should be pretty terrified by the negative effects of the unmanaged post-workout period. But now that you're afraid, I'm going to tell you exactly how you can best avoid the aforementioned problems.
In October of 2000, I was sitting in a conference center in Canmore, Alberta. There I was, listening to a presentation by one of the world's experts on post-workout and recovery nutrition (2). Up until this point, I thought I had a pretty good idea of how to eat during the post-workout period in order to maximize recovery. But after this presentation I realized that I had been missing one essential piece of the post-workout puzzle. In this article, grasshopper, I'm going to share the secrets with you.
For rapid recovery from exercise, immediately after a workout (strength or endurance), we must:
1. Rapidly replenish the low glycogen stores in our muscles
2. Rapidly decrease the muscle protein breakdown that occurs with exercise
3. Rapidly force further increases in muscle protein synthesis in weight trainers and/or restore muscle-protein synthesis in endurance athletes
In looking over this list, there are several things to keep in mind. First, remember that glycogen replenishment is important for several things. It's necessary for maintaining peak performance in both resistance and endurance training (3,4,5). In addition, if glycogen stores remain low, muscle protein breakdown can result and lead to loss of muscle mass (6). Finally, since glycogen attracts water to the muscle, the cellular hydration that results may stimulate new growth.
Another thing to consider is the protein balance factor. By rapidly increasing protein synthesis while simultaneously decreasing protein breakdown, you can shift to a positive muscle protein balance within 1 hour after the workout (7). Did you get that? You can recover within 1 hour!
Remember I said earlier that typically a trainee has to wait 24 hours for a positive muscle protein balance (1)? Unfortunately, even after this 24-hour period, recovery only means that there's at best only a neutral muscle protein balance (there's no longer breakdown, but building isn't occurring either). Using recovery nutrition, you can recovery nearly a day earlier that you otherwise would have!
And protein balance isn't just about muscle. If the body remains in a negative protein balance for too long, every cellular function can be affected. Hormones and hormonal precursors may be deficient. Neurotransmitters could be altered. And even the enzymes that are necessary for everything from cellular metabolism to digestion could be depleted. Not a pretty picture.
"Why are you putting so much priority on the post-workout period?" you might be asking. Well, it's because there are many parallels between the physiological effects of intense training and those seen in several illnesses. What happens during illness? Well, illness can lead to the degradation of many vital physiological processes. This degradation leads to stress on the body that can lead to further deterioration of the patient's condition.
In such situations, protein breakdown increases dramatically, creating the same negative protein balance as seen after a workout. Get it? Clinicians recognize the fact that the net negative protein balance seen in illness is a downward spiral that has to be stopped. So with proper nutrition and supplementation, they manage it. And that's exactly what athletes and weight trainers need to do.
So with the three important post-workout goals of increasing glycogen storage, increasing protein synthesis, and preventing protein breakdown in mind; I've devised a killer plan for attacking all three to promote optimal recovery after exercise. But I want to keep you in suspense for one more week before I tell you all the details. I know you'll spend the week in anxious anticipation but trust me, you won't be disappointed.
It's been a week since I laid out the main repercussions of training and how they manifest themselves during the post-workout period. So now that you've had a chance to think about that, I'm ready to drop the recovery plan. Are you excited? I hope so. I also hope the build-up has been pretty dramatic. You have to realize, I've had to wait years for this information.
With the publication of each new study, I could see that we were getting closer to understanding the post-workout puzzle. But, as Tom Petty once said, "the waiting is the hardest part". Finally, this year, with the culmination of a number of research projects, it's pretty clear what type of nutrition we need for optimal post-workout recovery.
Maximize Post-Workout Glycogen Synthesis
There are two key factors to rapidly increasing post-workout glycogen synthesis (8):
1. Adequate carbohydrate availability (to convert to muscle glycogen) (9)
2. High insulin levels (to stimulate glycogen storage and shuttle carbs into the muscle) (9)
Endurance athletes have traditionally been encouraged to consume 1.2 g of carbohydrate per kg of body weight immediately after training/competition (8,10). In addition, they are encouraged to continue this supplementation every 2 hours up until 6 hours after their exercise bout. Recent evidence, however, indicates that the addition of protein to a carb drink can actually increase insulin levels higher than carbs alone (11,12). There seems to be a synergistic insulin release with protein plus carbs.
The current recommendations for endurance athletes have therefore changed to include protein. Eating every 2 hours is still recommended, but now endurance athletes are encouraged to consume 0.8 g of carbs per kg of bodyweight in combination with 0.4 g of protein / kg of bodyweight. This means that a 154 lb endurance athlete should be consuming 56 g of carbs and 28 g of protein at each meal: right after training, and 2, 4, and 6 hours after training.
Since most of the research on this topic has been done in endurance athletes, we have to speculate about what strength athletes would need in this regard. From the research, it's clear that strength athletes actually have higher glycogen synthesis rates after exercise than endurance athletes so they can more rapidly refill their glycogen stores (13).
But since strength athletes don't deplete their glycogen stores as badly as endurance athletes, they would need fewer total calories. With this said, I believe it's reasonable to suggest that a strength athlete consume one meal of 0.8g of carbohydrate and 0.4 g of protein / kg of body weight immediately after training.
This means that the 154 lb weight lifter would need 56 g of carbs and 28 g of protein while the 220 lb weight lifter would need about 80 g of carbs and 40 g of protein after a weight-training workout. Since glycogen synthesis rates are so high in strength athletes, they would only need to consume this type of meal immediately after the workout and then resume normal eating about 2-3 hours later.
If the strength athlete is in a bulking cycle, the post-workout recommendations would include 2 servings of recommended formula, one immediately after training and one 30-60 minutes later. Normal eating could be resumed 2-3 hours later.
A couple of final factors need to be discussed. First, the research is very clear that if you wait to consume your post-workout nutrition, you lose (14). One study showed that if the post-workout beverage was consumed immediately after training, glycogen synthesis was three times higher than if the beverage was consumed just two hours later. So the sooner you drink the drink, the better the recovery rate.
Secondly, with respect to the types of carbohydrate and protein to consume, it's clear that immediately after training, liquid nutrition is best tolerated (8,15). Since liquid nutrition is more rapidly digested and absorbed, nutrients are more rapidly delivered to the muscle. In addition, according to the literature, the optimal carbohydrates to consume are glucose and glucose polymers, like maltodextrin (8).
As far as the best protein to consume, you want to choose a protein that is absorbed as rapidly as the ingested carbs so that the synergistic insulin response can be maximized. Now that's hard to find. Most intact proteins (yes, even in powdered form) take several hours to be fully absorbed. We need protein that can get absorbed within minutes, just like the carbs do. Without this simultaneous absorption of both, the insulin response will be disappointing. So what to do? Well, since one of the most quickly digested proteins is whey hydrolysate, it's the protein of choice for our purposes here (10).
Stop Protein Breakdown Dead in its Tracks
The scientific literature is pretty clear in terms of how to prevent post-workout protein breakdown. And it can be summarized in one word... Insulin.
In previous years, scientists knew that the hormone insulin had a big impact on muscle-protein balance, but they just couldn't figure out if it impacted the synthesis or breakdown. Several studies within the last few years, however, have indicated that insulin is the main regulator of post-workout protein breakdown.
In one very detailed study published in May of 1999, it was clearly demonstrated that at rest, high blood levels of insulin increased protein synthesis by about 67% while not changing protein breakdown (16). However, during the post-workout period, insulin infusion decreased protein breakdown by about 30% without impacting protein synthesis.
The authors of this study concluded that at rest, insulin was anabolic, while after exercise insulin was anti-catabolic. These results have been validated by other studies showing that high blood levels of insulin considerably diminish post-workout protein breakdown without impacting protein synthesis during the post-workout period (17).
So the bottom line is that insulin is not anabolic after workouts, but it sure is anti-catabolic. And that's great because insulin is easily controlled. Also, since protein breakdown predominates during the post-workout period, getting the insulin up allows muscle breakdown to diminish so that synthesis can dominate and we can quickly get back to building muscle!
And don't forget that insulin causes vasodilation. This means the vessels "open up" and transport more blood (and nutrients) to the cells. Can you say "feed the muscle!"? And yes, that extra blood flow is full of the protein, amino acids, and carbs that you'll be ingesting immediately after the training session.
So how do we get insulin up after a workout? Well, you could always become a human pin cushion and inject your insulin right into the subcutaneous area of your abdomen. But I think there are better and certainly safer ways.
First, as mentioned earlier, by eating protein with carbs, insulin levels are higher than with carbs alone (10, 11). In the aforementioned studies the insulin response to 0.8 g of carbs/kg (in the form of glucose and maltodextrin) plus 0.4 g of protein/kg (in the form of protein hydrolysate) was 103% higher (double) than the insulin response to an equal amount of calories coming from carbs alone (1.2 carbs /kg). So the very same carb/protein beverage that we're relying on for maximizing glycogen storage is also preventing protein breakdown (10, 11). Sweet!
Secondly, certain amino acids can increase the insulin response to meals. By adding certain amino acids to the carb/protein beverage in the above study, the insulin responses were considerably higher than the carb/protein beverage alone (10, 11). In addition, research in the 60s shows that specific amino-acid combinations were more effective than others at increasing insulin release (18). So it looks like carbs + protein + amino acids is the way to go.
Complete Your Recovery by Jacking Up the Protein Synthesis...
The final piece of the post-workout puzzle is the management of protein synthesis. And although this area is a little more complex than managing protein breakdown, there are three key ingredients to increasing protein synthesis immediately after workouts:
1. A proper ratio of BCAAs
2. High blood levels of essential amino acids
3. High blood levels of insulin
In the past, a high protein intake was recommended after workouts in order to increase protein synthesis. Actually, in the Protein Roundtable I even recommended a really big protein intake immediately after the workout in order to increase protein synthesis. Well, I'm here to say that I may have been a bit off base. Yeah, yeah, I'm admitting I may have been wrong, so cherish the moment and feel free to poke fun at me the next time you see me.
Based on the research, it appears that the amount of protein intake has very little to do with pushing protein synthesis up after workouts. And in fact, too much could be counter productive (more on this later). More important to increasing protein synthesis after workouts is the ability to rapidly deliver the right type of protein or, more correctly, the right type of amino acids. In a paper published last February, researchers discussed rates of protein synthesis during several conditions (7):
1. At rest with increased insulin levels, protein synthesis increased by about 50% when compared to normal insulin levels (21).
2. At rest with high amino acids in the blood, protein synthesis increased by about 150% when compared to normal blood levels of amino acids (22).
3. After weight training, protein synthesis increased by about 100% vs. pre-training values (23).
4. After weight training with high amino acids in the blood, protein synthesis increased by 200% vs. after weight training with normal blood amino acids (22).
5. After weight training with high amino acids in the blood and high insulin in the blood, protein synthesis increase by over 400% vs. normal post-workout amino acid and insulin levels (7).
The most interesting thing was that in the last condition, the post-workout beverage only contained 6 g of protein and 36 g of carbohydrate. As long as insulin was high and correct amounts of essential amino acids and BCAAs were present, protein synthesis got jacked after the workout.
Several other studies have shown that either infused or orally administered post-workout amino acids are able to rapidly increase protein synthesis as well as rapidly create a positive muscle protein balance after training (24, 25).
Interestingly, it seems that non-essential amino acids are not required for this process and that if only essential amino acids are supplied, there's no difference in the increases in protein synthesis (7, 26). Either way, the key seems to be this "infusion" concept where amino acids are very rapidly delivered to the blood. Again, whey hydrolysate is the quickest orally available protein for the blood unless you want to go ahead and hook up to the amino-acid IV drip.
You may be asking yourself why too much protein could be counterproductive. Well, a very high protein meal can actually cause a release of glucagon. Glucagon is a hormone that antagonizes insulin release. So if you eat some protein with carbs, insulin shoots up. If you eat too much protein with carbs, the insulin release may actually be lower. And if this weren't bad enough, glucagon also has another function that we want to avoid. The darn stuff causes the body to convert amino acids into glucose (a process called gluconeogenesis). So take in too much protein and say goodbye to that special amino acid ratio. Instead those aminos become carbs!
Let's get back to the amino acids. In addition to the requirement for rapidly delivered essential amino acids, BCAAs seem to play a big role in the recovery and increase of protein synthesis after a workout (2,7). Unpublished data presented at the 2000 Canadian Society for Exercise Physiology Meeting shed light on the importance of BCAAs in recovery (2). In endurance athletes, post workout protein synthesis rates will drop by about 30% for up to 6 hours after a training bout. Providing carbohydrates to these athletes, while favorable for increasing muscle glycogen stores, has no ability to increase protein synthesis.
However, a drink providing only the BCAA leucine was able to promote full recovery of post-workout protein synthesis levels to pre-training values. In addition, by adding carbohydrate to the beverage, protein synthesis was higher after the workout than before the workout. Since this beverage increased blood insulin levels, the author of the study concluded that insulin indeed had a synergistic effect with leucine on protein synthesis.
The results of this study and others have lead researchers to believe that within the muscle cell, there's one particular regulatory pathway for protein synthesis that's stimulated by insulin, but dependent on leucine (27). If insulin is present and leucine isn't, then protein synthesis can't maximally be stimulated. If leucine is present and insulin isn't, protein synthesis can't be maximally stimulated. But give 'em both and look out!
Since leucine has this great impact on muscle protein synthesis and since levels of leucine, much like glutamine, decline during exercise, it only makes sense to supplement with leucine after workouts (28). In the end, it appears that leucine, along with protein and carbs, will lead to the greatest increases in protein synthesis.
So what's the best way to rapidly increase protein synthesis after a workout? It seems that the 0.4g/kg of protein hydrolysate plus 0.8g/kg of glucose/glucose polymer plus insulin-stimulating amino acids takes care of the insulin angle. But remember, insulin isn't enough. Providing BCAAs in an ideal ratio is the second part in rapidly stimulating protein synthesis.
The Grand Finale
That's it. The ideal post workout combo that maximizes your growth and recovery potential. Whew, that's a lot of science! I hope I didn't lose you along the way because I honestly believe that this article is the most important I've ever written for T-mag.
Compiling years of good post-workout science has enabled me to devise a plan of attack for optimal post-workout nutrition. And this plan of attack is designed with only one goal in mind... optimizing recovery for every human being that works out, regardless of the type of exercise they do.
Remember, to be effective, post-workout nutrition has to...
* Increase glycogen stores
* Increase protein synthesis
* Decrease protein breakdown
Interestingly, several nutrients such as glucose and glucose polymers, protein hydrolysates, and amino acids can all work together with overlapping functions in order to accomplish all three goals. No drugs necessary!
At this point, before the jaded cynics write in shouting about how this article is probably nothing more than a thinly veiled attempt at introducing a new Biotest supplement, I'm gonna' head them off at the pass. This isn't a thinly veiled attempt at introducing a new supplement. It is a full fledged, in your face, introduction to a new Biotest supplement .
This supplement uses every glorious piece of available nutritional science to support its claims. Because about 95% of the idea behind the formula is founded on nothing but hard data, very little of this article is theoretical. If you don't believe me, go look up the references yourself.
If that's not enough, the very formula that Biotest plans to launch is currently being evaluated in my lab. Unlike other companies, Biotest will actually have supporting data before the product is launched. Rest assured, T-mag readers will be the first to read about the results (which will be posted on this very site within the next few weeks).
The better part of the last year has been spent putting together the ideal post-workout protein formula that can maximally stimulate glycogen and protein synthesis while decreasing protein breakdown in all types of athletes. Since the formula is based only on nutrients that occur naturally in food, it has no banned or potentially harmful substances. It's therefore useful for all athletes from triathletes to power lifters and from those in high school to those competing in the professional ranks. Each and every trainee who wants a better physique and each and every athlete who wants to improve their training and their performances has something to gain by taking it.
Stay tuned because over the next few weeks we will be discussing the data collected in the lab (complete with charts and graphs). In addition, T-mag will be doing a series of Q&A articles about the new formula. T-mag has been getting quite a bit of excited feedback and many questions, so I'll be answering them in these articles.
The topics for some of the upcoming articles include questions of post-workout nutrition including issues about GH release, questions on fat burning, and questions about post-exercise caloric expenditure.
References for Part 1 and Part 2
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2. Meeting - Canadian Society for Exercise Physiology; 2000.
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26. Journal of Nutritional Biochemistry; 10, 89-95, 1999.
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