I recently co-authored a new study that investigated increases in intracellular hydration following performance of 16 weeks of bodybuilding-type resistance training. I am pleased to say that the study -- a collaboration with colleagues at Londrina State University in Brazil -- has just bee...
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February 3, 2014
I recently co-authored a new study that investigated increases in intracellular hydration following performance of 16 weeks of bodybuilding-type resistance training. I am pleased to say that the study — a collaboration with colleagues at Londrina State University in Brazil — has just been published in the European Journal of Sports Science. Here is a summary and what to take home from the findings.
It has been well-established that regimented resistance training results in increases in muscle hypertrophy (i.e. growth). The mechanical forces associated with lifting cause an adaptive response that results in increases in the contractile elements (actin and myosin) as well as structural proteins of muscle. These adaptations ultimately facilitate the muscle to be able to exert greater amounts of force. It’s a basic adaptive response to a stress (i.e. a survival mechanism) that makes us stronger so we can handle similar future events if and when needed.
There has been extensive debate as to whether resistance training also increases non-contractile (sarcoplasmic) hypertrophy. Non-contractile elements include things such as collagen, organelles, and fluid. The fluid component is one of the more intriguing areas of discussion. It’s no secret that resistance training can have an effect on altering intramuscular water — the “pump” is a well-known phenomenon in bodybuilding-type training. But what remains unclear is whether resistance training can increase intracellular water chronically over time. Our study sought to shed light on this topic.
What We Did:
A total of 64 college-aged subjects (30 men and 34 women) participated in the study. Subjects engaged in a supervised progressive resistance training program carried out 3 non-consecutive days a week over 16 weeks. Training consisted of a bodybuilding-type routine whereby 3 sets of 8-12 reps were performed with 60-90 seconds rest between sets. A total of 11 exercises were performed per session using a combination of free weights, cables, and machines. All sets were taken to the point of momentary muscular failure.
Bioelectrical impedance spectroscopy (BIS) was used to measure total body water, intracellular water and extracellular water content. BIS is a validated tool for measuring body water and its various sub-fractions. Assessments were made at baseline, the mid-point of the study, and at study’s end.
Intracellular water was significantly increased following training in both men and women. The effect size — in simple terms, a measure of the magnitude of results that takes into account variance between subjects — was considered moderate, indicating the results are meaningful. Both men and women showed approximately equal responses as to increases in intracellular water over the course of the study.
As noted, this study provides compelling evidence that regular bodybuilding-type resistance training leads to an increase in sarcoplasmic hypertrophy. Why should anyone care about increasing the water content of muscle? Well, there is a large body of research showing that cell swelling via increased intracellular hydration results in marked increases in protein synthesis and reductions in protein degradation; a hypertrophy homerun. These findings have been shown in a wide variety of cell types, implying that keeping muscle fibers hydrated may actually increase contractile hypertrophy and thus enhance strength.
Now it’s important to note that these observations are from in vitro (i.e. test tube) data. Whether similar results play out in practice in hard-training lifters is still unknown and need further study. That said, the aforementioned findings certainly suggest that there may well be an anabolic effect (and in fact one of the hypotheses for hypertrophic effects of creatine is its role as an osmolyte).
What remains unclear is whether the increased intracellular hydration is specific to bodybuilding-type training or inherent with all types of lifting. We speculated that results of the current study may have been due to increased glycogen storage. Bodybuilding-type training relies primarily on fast glycolysis to fuel performance, whereby carbohydrate is the primary energy source (as opposed to powerlifting-type training, which relies primarily on the phosphagen system). As such, the body adapts by increasing its capacity to store glycogen. Since glycogen attracts 3 grams of water for every glycogen granule, it stands to reason that this was responsible for the increased hydration status.
We are currently designing a study that will compare chronic changes in water sub-fractions following bodybuilding- versus powerlifting-type training. The hope is to begin data collection before the year is out. Stay tuned.
Ribeiro AS, Avelar A, Schoenfeld BJ, Ritti Dias RM, Altimari LR, Cyrino ES. Resistance training promotes increase in intracellular hydration in men and women. Eur J Sport Sci. 2014 Jan 28. [Epub ahead of print]
January 20, 2014
Here is my speaking schedule for 2014. I’ll update the page as new dates are added.
• January 24: Private Seminar, Bath, UK
• January 25: Private Seminar, London, UK
• March 21: Sports Nutrition and Human Performance Conference, Tampa, FL
• May 2-3: Fitness Summit, Kansas City, MO
• May 15-16: BodyPower, Birmingham, England
• May 30-June 5: Private Seminar, Reykjanesbaer, Iceland
• June 21: ISSN National Conference, Clearwater, FL
• June 28: ISSN Europa, Hartford, CT
• July 11: NSCA National Conference, Las Vegas, NV
• July 26-27: Private Seminar, Limerick, Ireland
• August 7-10: CanFitPro, Toronto, Canada
January 15, 2014
There’s certainly no shortage of fitness blogs on the internet. Everyone who’s ever lifted a weight seems to have one. Problem is finding those that have solid info backed by research and experience.
In an effort to separate the gold from the silt, I’ve compiled a list of fitness blogs that IMHO consistently deliver the goods. They provide info you can trust. No hype. No bro-science. Just quality fitness content.
A few caveats before proceeding. First off, the list is in no particular order — placings are not indicative of one blog being better than another. Rather, the blogs are all inherently different and unique, and therefore provide complementary reading. In addition, the list is not intended to be comprehensive. There are certainly a lot of other excellent blogs that are not mentioned here. I had to keep the number of entries manageable so I limited it to a dozen (actually a baker’s dozen, but who’s counting ).
With that out of the way, on with list.
Bret Contreras: If you could only read one fitness blog, this is the one I’d recommend. No one puts out more quality content than Bret. It is really amazing how many posts he pens, but even more amazing that the info he provides is so consistently cutting-edge. There is a focus on glute training (he is “The Glute Guy” after all), but there’s also tons of posts on pretty much every aspect of exercise. Importantly, the info is always presented in a balanced fashion; there’s never an agenda furthered.
Weightology is a blog written by James Krieger. I’ve known James for years and collaborated with him on a number of research-based projects. Hands down he’s one of the brightest minds in the fitness industry. Much of his blog is pay-to-view, but there also is a good amount of free content as well. When James posts, you can bet the info is scientifically sound.
Alan Aragon: I’ve said it before and I’ll say it again, no one has a better grasp of the practical application of nutrition to exercise than Alan. As would be expected, his blog is great…except for one little thing: He’s too busy dominating the nutritional stratosphere to write many posts. Fortunately, when he does decide to post it’s invariably a homerun. For Exhibit A, check out this now-legendary rebuke of fructose alarmism. Side note: The comments section is just as compelling as the article with a guest appearance by Dr. Lustig himself!
Eric Cressey: In case you don’t know, Eric Cressey is one of the most sought-after strength coaches for baseball conditioning. Players come from all over the country to train at his facility, Cressey Performance, including many top pros. His blog includes baseball-related contditioning info but focuses more on general S&C info, including lots of discussion about mobility and stability drills. Best of all, he posts numerous teaching videos that demonstrate concepts discussed in the articles. Always a great read.
Born Fitness: This blog is written by Adam Bornstein, former editor for Men’s Health and Livestrong. Adam has keen insight into what fitness topics people want to read, and an innate ability to convey the info in an interesting fashion. He’s knowledgeable about exercise, and astute enough to consult with experts when needed. Bonus points for having one of the most well-designed sites as well.
Exercise Biology: This blog is written by Anoop Balachandran. Anoop has a terrific grasp of the exercise literature (he’s currently pursuing his PhD in ex phys), and understands the practical implications for the general public. The content is always evidence-based, with lots of discussion about the application of research into practice. When you fnish reading the blog, scan through the forums; they often contain high-level discussions as well.
Lou Schuler: Lou is perhaps the best pure fitness writer I’ve encountered. He has a knack for being able to present technical topics in a manner that is easily-digested, and usually does so in a humorous way. Similar to Adam Bornstein, Lou was a former editor at Men’s Health and other fitness mags. As such, he always seems to be at the forefront of what people want to know fitness-wise.
Nick Tuminello: Nick is another guy who amazes me with the number of articles he writes. He’s truly a writing machine. Nick posts on a variety of topics and isn’t afraid to tackle some controversial issues. He’s got a good sense of research and provides innovative training strategies based on a combinatoin of evidence and experience.
Burn the Fat, Feed the Muscle: This blog is written by Tom Venuto. As the name implies, the blog primarily focuses on how to optimize body composition. Tom is a former bodybuilder and his approach borrows from many of the popular bodybuilding principles. But Tom isn’t just some bro. He’s well-versed in exercise science and dishes out advice in an evidence-based fashion. You won’t read about “peaking the biceps” or “carving out an inner chest.” You will read about time-tested training practicies that will help you attain a better physique.
Dean Somerset: Dean has more of a post-rehab focus than the others on this list. Accordingly, you can get a fresh take on topics that aren’t well covered elsewhere. While much of the posts delve into the medical fitness arena, there also are some good general training articles as well.
Body Recomposition: This is Lyle McDonald’s blog. Lyle is probably best known for writing about ketogenic diets, but he is highly knowledgeable in many areas of nutrition. Over the years he’s been an innovator in the field, using research to develop strategies for optimizing fat loss. Lots of evidence-based info about fitness on his site, particularly pertaining to diet.
Robertson Training Systems: This blog is penned by Mike Robertson, a popular strength coach based out of Indianapolis. Mike mostly focuses on performance-based topics with an emphasis on exercise technique. That said, there’s a little bit of something for everyone here, including some interesting interviews with up-and-coming fitness pros.
Tony Gentilcore: Tony is a partner with Eric Cressey in Cressey Performance. His blog covers serious training topics, but generally does so in a humorous manner. The topics are fairly diverse and the supporting videos he posts are first rate. What sets Tony apart is his fluent and engaging writing style that continually holds your interest. Always entertaining.
January 12, 2014
My journey began a little more than 3 years ago, but in actuality it had been in the works for a lot longer. The idea of obtaining a PhD in exercise science came about while I was pursuing my Master’s degree in 2008. By the time I started working on my Master’s thesis, the thought was in the forefront of my mind; upon graduation, it had become my ultimate goal.
One little problem. I had a thriving career and, being in my 40s, was not about to chuck everything and become a full-time student. It simply wasn’t an option.
My alternatives were very limited. There simply weren’t many programs that provided a platform to getting a doctorate while you worked. Even fewer had programs that were within my area of interest. Yet I was committed to finding a viable solution.
After months of investigation, I learned that Rocky Mountain University in Provo, Utah had a hybrid PhD program that combined online and on-site coursework, thereby allowing the ability to go to school while working full-time. Better yet, Dr. Brent Alvar was the program director of the university. I was very familiar with Dr. Alvar’s work. He did the pioneering research on the dose-response relationship of resistance training, and was the mentor to many leading researchers during his tenure at Arizona State University.
For those who don’t know, the most important criteria in choosing a doctoral program is the person in charge of the program. This is who will be mentoring you throughout your studies. If the relationship doesn’t work or if your interests are out of sync, you’re basically wasting your time.
I spoke with Dr. Alvar by phone. We hit it off immediately. He told me about the coursework. I told him about my situation. He said it would be tough but doable. He said I was exactly the type of student he enjoyed mentoring. That was all I needed to hear. I applied the next day. A month later I was accepted into the program.
I began studies at RMU in March of 2011. For the next two-and-half years I had little time to myself. Between work and school, my social life was virtually nonexistent. Coursework was intense. We had 4 to 5 classes per semester working on a trimester schedule — i.e. there was almost no break between semesters. In addition to writing multiple research-based papers, each course required weekly online forum discussions throughout the term. Most courses had comprehensive tests as well. Once every semester I had to travel to Provo for a week of intensive in-class study. Classes met Monday-Friday from 8:30 am to 5:30 pm with an hour for lunch. Those were some loooong days!
The majority of my coursework was centered around research. I took three biostats classes, two classes in research methods, two classes in epidemiology, and other related courswork such as dissertation proposal writing and grant writing. Oh yeah, and there were the core classes as well. Our initial class had 15 cohorts; by the end of the program, only 9 of us remained. Suffice to say, the program was intense.
There also were four “independent project” courses. These courses afforded the ability to work on research by writing papers specific to our area of interest. I used the opportunity to write four review articles that were ultimately published in major peer-reviewed journals. I also was able to integrate the material into my dissertation review of literature. Without question, these classes were highly productive.
I finished up coursework in July of last year. I immediately took (and passed) my comprehensive exams so I could begin data collection for my dissertation study. The study was something I’d been planning since my Master’s class in research methods. I actually wrote up a proposal in that class which was quite similar to the study I ultimately carried out. The study itself examined muscular adaptations between bodybuilding- versus powerlifting-type training in experienced lifters. There were several novel findings from the study that will certainly add to our understanding on the topic, with important implications for program design. The manuscript is currently in journal review. I’ll be discussing the results at length upon publciation.
This past Friday I defended my doctoral dissertation. The day seemed as if it would never come. The defense was held in Indianapolis at the NSCA Coaches Conference. My dissertation chair, Dr. Alvar, was present in the room. My other committee members, Dr. Nicholas Ratamess and Dr. Mark Peterson, were beamed in by the wonders of online technology. I gave a half-hour powerpoint presentation. I was then grilled for about 45 minutes on a wide array of topics about my study and its implications for future research.
After answering all questions, I was asked to step out of the room. I probably waited about 10 minutes but it felt like an hour. Finally Dr. Alvar opened the door and uttered the words, “Congratulations Dr. Schoenfeld…”
It was one of the most satisfying moments of my life. Just a huge feeling of accomplishment. So much work. So much sacrifice. All coming to fruition in the form of a doctoral degree — the ultimate testament to being a content expert in your area of study. My only regret was that my father was not around to share in the experience — he instilled the scientific method in me from the time I was young and would have probably been even happier than me with the achievement. Hopefully he’s watching somewhere from above.
So what’s next? I will continue exploring a wide variety of educational pursuits. My life’s work is to make a difference in the fitness realm, to have a positive impact on people’s lives. We have a limited time on earth; it’s imperative that we use our time wisely.
In addition to teaching at the college level, I’m currently involved in numerous research studies that will shed light on important topics in exercise science and sports nutrition. I’ll also be speaking across the country and around the world over the coming months, lecturing on how to apply the science of training and nutrition into practice. I’ll still work with a select group of individual clients for one-on-one training consults as well as serving in an advisor capacity to various corporations. And of course I’ll be involved in writing more articles and books targeted to fitness professionals and consumers, detailing the best practices to optimize results.
I feel very blessed to be an educator and make an impact. I look forward sharing the knowledge I’ve gained. I’ll be doing so right here on this blog. Stay tuned.
December 28, 2013
As 2013 comes to an end, here are some random thoughts and goings on that I’d like to share:
• First and foremost, I’ll be defending my doctoral dissertation in a matter of weeks. The defense will mark the culmination of years of study and research. My dissertation paper titled, “Effects of different volume-equated resistance training loading strategies on muscular adaptations in well-trained men,” was submitted last week for peer-review. I’ll have lots more to say about the results in short order. Looking forward to completing this phase of my education and excited to enter the next phase in my never-ending quest for knowledge and enlightenment in exercise science.
• I was disappointed, although not entirely surprised, that Dr. John Ivy did not respond to my offer to publish a rebuttal to my critique of his recent review on nutrient timing. As discussed in my critique, the review by Dr. Ivy was a classic case of cherry-picking research to support a closely-held opinion while conveniently neglecting to mention compelling evidence to the contrary. This type of article would be expected in the muscle rags, not in a peer-reviewed journal. If Dr. Ivy truly believes the evidence supports his position, I challenge him to debate me on the topic. He can pick the time and place. Let’s put all the info out there and allow the public to decide. It’s how science is supposed to work.
• Speaking of nutrient timing, I was interviewed by Carl Lanore on Super Human Radio about my recent paper, The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. Carl always does a superb job asking the right questions and allowing leeway for scientific discussion. Some very important info discussed here, not just about nutrient timing, but also as to how to put research into proper perspective for practical decision-making. Here is a link to the interview.
• I’ve had several peer-reviewed papers either published or accepted for publication within the past few weeks. My paper co-authored with Bret Contreras titled The Muscle Pump: Potential Mechanisms and Applications for Enhancing Hypertrophic Adaptations was just published ahead-of-print in the Strength and Conditioning Journal. This article discusses how cell swelling associated with resistance exercise can provide an anabolic stimulus that potentially increases muscle growth. On a related topic, I just received acceptance from the European Journal of Sports Science on a study that I collaborated on with researchers from Brazil showing that bodybuilding-type resistance exercise results in a long-term increase in cellular hydration. This has important potential implications for muscle growth. Finally, another article I co-authored with Bret, Is Postexercise Muscle Soreness a Valid Indicator of Muscular Adaptations? has been made available to be viewed for free by the NSCA. Normally articles published in the Strength and Conditioning Journal are only viewable at no charge for members. I’m not sure how much longer the opportunity will last, so if you haven’t read the article as yet I’d encourage you to download it now.
• Last but not least, here is Episode 7 of the B&B webcast covering evidence-based fitness prescription. Contrary to popular belief, evidence-based practice is not simply a matter of knowing the research; it involves synthesizing the current body of evidence and then combining this knowledge with personal experience and taking the needs and abilities of the individual into account. In this episode we delve into the topic in depth and discuss how to blend the science and art of fitness to optimize training programs.
That’s all for now. 2013 has been a great year, but 2014 should be even better. Look forward to making a meaningful contribution to our understanding of the science and art of fitness and nutrition, and of course sharing that knowledge with you all.
Stay well and stay fit!
December 8, 2013
This is a guest post from the good folks at Examine.com, who do a great job providing objective research-based info on pretty much all areas of nutrition and supplementation. It’s an important topic that all-too-often is misunderstood by the general public. Thanks to Sol Orwell and his team for explaining the concept in an easy-to-understand manner and exploring its practical applications. For those interested in the technical aspects, I would recommend you read the paper by Thomas et al. A Mathematical Model of Weight Change with Adaptation.
Calories in versus calories out is one of the fundamental ‘laws’ of nutrition. Though it upholds both the law of thermodynamics and the conservation of mass, the calories in versus calories out theory doesn’t hold up when applied to the human body. If anything, it is a guiding statement based on a law.
When looking at a true closed system (humans don’t count), any possible conversions of energy can be predicted down to a single joule, with nearly 100% accuracy. This is because our equations for energy transfers in closed systems are very good.
When looking at an open system, like the human body, we also have a set of equations we can rely on. Unfortunately, they’re not quite as good as their closed-system counterparts. As an example, lets look at the most commonly used equation to determine caloric expenditure and your basal metabolic rate.
The Harris-Benedict formula for men:
88.362 + (13.397 x bodyweight in kg) + (4.799 x height in cm) – (5.677 x age in years)
The Harris-Benedict formula for women:
447.593 + (9.247 x bodyweight in kg) + (3.098 x height in cm) – (4.330 x age in years)
Don’t forget to multiply by the ‘activity’ factors. Use 1.2 if you are sedentary, 1.375 for light exercise, 1.55 for moderate, 1.725 for heavy, and 1.9 for intense exercise.
The above calculations are pretty good, since the parameters being measured (gender, weight, height, age, and activity level) account for a lot of variation in the metabolic rate between individuals.
Still, it’s not an absolute rule. There are many other factors that influence the metabolic rate that are not included in the Harris-Benedict equation. These include:
• Adipokine status, including leptin, adiponectin, and resistin.
• Thyroid hormone status
• Steroid hormone status, including estrogens and androgens, as well as DHEA.
• Mitochondrial efficiency and ‘uncoupling’, also known as thermogenesis.
The formula doesn’t include these factors because it is impractical to expect people filling out a BMR equation to know their mitochondrial efficiency.
Moreover, the activity levels are vague. What feels ‘intense’ to one person could be ‘moderate’ to another. A misinterpretation of activity levels for someone with a 2000kcal intake could result in a difference of up to 700kcal.
Calories in, as a concept, is fundamentally hard to predict. Differences in food absorption, whether due to genetics, nutrient co-ingestion or even the shape of the chyme in your stomach are hard to account for. The differences in nutrient partitioning after absorption, or whether the nutrients go to muscle, glycogen or fat are even harder to predict.
Don’t forget that calorie counts are not absolute. Though a food label may list “70kcal” as the caloric value for one serving size, a more accurate description is “70kcal, give or take a 5% margin of error.”
Does this mean I shouldn’t worry about calories?
No, no, and no. Despite the above complications, calories do matter in concept, and having even a rough grasp on caloric intake is invaluable. The only change that needs to happen is how you view your caloric intake.
Instead of deciding to eat 2,357 calories a day to maintain weight, eat “a little above 2,000 calories.” Rather than deciding to cut 500 calories from your daily diet to lose a pound of fat per week, aim to eat approximately 500 less calories per day, and track how your body responds.
At any point during the day, you should be able to accurately estimate your caloric intake, as well as how many calories you have left to eat that day. Instead of expecting a perfect caloric count, aim for +/- 200 calories of the true value.
A relaxed but consistent style of nutrient tracking means you’ll be hitting your goals and stressing less about it. Best of all, you’ll never feel constricted because your favorite food would put you over your limit by 50 calories. Just remember: being relaxed doesn’t mean you’re not determined.
Written by Kurtis Frank and Dr. Spencer Nadolsky. Both are directors at Examine.com, an independent and un-biased organization that focuses on evidence for supplementation and nutrition.
December 7, 2013
I’m happy to report that the meta-analysis on protein timing that I co-authored with Alan Aragon and James Krieger has been published in the Journal of the International Society of Sports Nutrition. The study has created quite a stir, provoking discussion and debate in numerous forums. As a testament to its impact, the study already is in the top five most viewed articles for the JISSN over the past year at the time of this writing — less than a week after its publication!
This post will recap the study and provide consumer-friendly practical application of results. Before getting into particulars, however, here is a brief overview as to how it all came about.
A Little Background
For many years I was a staunch proponent of the concept of an “anabolic window of opportunity,” advocating that protein and carbs needed to be consumed within about an hour post-workout to maximize the hypertrophic response to an exercise bout. I’d read the seminal text by Poortman and Ivy that championed the approach. I’d seen numerous studies suggesting the presence of a narrow window, including the JISSN position stand on the topic. I’d heard a number or prominent researchers in the field lecture at conferences on the importance of quickly ingesting nutrients after resistance training for promoting anabolism. The evidence seemed pretty overwhelming – a no-brainer.
A couple of years ago, I asked my good friend and colleague Alan Aragon – one of the preeminent sports nutritionists in the world – to review the nutritional chapter for my book, The M.A.X. Muscle Plan. In doing so, Alan challenged my recommendation as to the importance of nutrient timing. He pointed out various flaws in the underlying science. He put forth the hypothesis that the concept was largely overhyped.
I was intrigued.
I did a thorough literature search, combing through all the relevant studies, both acute and long-term. And guess what? The more I looked into the matter, the less convinced I was at the veracity of supporting evidence for a narrow anabolic window. It became evident that the staunch proponents of nutrient were cherry-picking studies to support their position while ignoring conflicting research. Moreover, there were important limitations in many of the studies favoring timing that often were not properly addressed. It was clear to me that a balanced review was needed to provide clarity on the topic.
Over the next several months Alan and I delved in head-first, discussing the body of research in context and developing evidence-based conclusions. This process ultimately led to a change in our perspectives, with both of us moving more to the center (as reflected in our practical recommendations). The final product was titled Nutrient Timing Revisited: is there a post-exercise anabolic window?, published in JISSN earlier this year. It is now by far the most popular article in the history of the journal and has been highly cited in subsequent research.
One thing that really struck me when reviewing the literature was the disparity in longitudinal studies; some showed clear increases in muscular adaptations while others did not. A major issue with long-term training studies is that they have small sample sizes; the time and costs associated with such research limit the number of participants that can be evaluated. It was certainly plausible that studies showing no effect simply lacked the statistical power to note a significant difference (a so-called a Type II error). The only way to evaluate the topic and provide a valid quantitive analysis of findings was to conduct a meta-analysis, where the data from all relevant studies are pooled to achieve optimal statistical power. I spoke with Alan about the undertaking. We contacted nutrition and statistical whiz James Krieger. The rest, as they say, is now history…
Data Collection and Findings
The meta-analysis took several months to complete. We decided on appropriate inclusion/exclusion criteria, coding variables, and other info relevant to the analysis. We were meticulous in our approach, checking and rechecking data for accuracy. Most importantly, we remained unbiased and objective throughout; none of us had any idea what we would find nor did we care. The only thing that mattered was getting clarity on the topic.
It was a very involved process, with an endless number of email exchanges and phone calls. We continually reassessed our methods so that results would properly reflect the body of literature. The most frustrating part was not being able to get any preliminary findings until all coding was complete. Patience was a virtue
The first analysis looked at the basic data. In other words, we did a simple pooled analysis to see if there were any increses in muscle strength or hypertrophy from protein timing. No effects were seen with respect to strength but, lo and behold, there was a small but significant effect on muscle hypertrophy. Had we effectively confirmed the existence of an anabolic window?
Not so fast…
Over the next couple of days we ran sophisticated regression analysis whereby a number of variables (i.e. covariates) were examined independently to evaluate their impact on results. This produced the most interesting finding of all: the quantity of protein explained virtually all the variance in results! Specifically, a majority of studies did not match protein intake between groups: the experimental group consumed substantially more protein than the controls. Thus, the average protein consumption in the control groups were well below what is deemed necessary to maximize protein synthesis associated with resistance training. Only a few studies actually endeavored to match intake. We did a subanalysis of these studies. No effects were found on protein timing (and this was in spite of having to discard a study that showed no effect because of insufficient available data).
Practical Implications and Other Observations
The take home message from the meta-analysis is that there does not appear to be a narrow “anabolic window of opportunity”; for the vast majority of the population it really doesn’t matter whether you consume protein immediately after training or wait for a couple of hours. This should be liberating for most lifters. You don’t have to worry about slamming a shake the minute you finish lifting. It’s okay to relax a bit, do whatever you need to do, and get in your post-workout nutrition when its convenient.
Now the findings of our study come with several caveats. For one, our criteria for timed consumption was < 1 hour pre- or post-workout, while the non-timed groups were > 2 hours. It is not clear if waiting say 5 hours or more after a training session would have a negative impact. In my previous review with Alan, we proposed that a window probably exists, but it is rather wide (4-6 hours) and will depend on when you ate your pre-workout meal. Our findings in this meta-analysis do nothing to change these guidelines.
Another important point is that there is a paucity of studies that have matched protein consumption between the timed vs untimed groups. Although our subanalysis failed to show any differences, statistical power was lacking and it remains possible that there may be an underlying effect that we were not able to detect. We need more well-controlled research where intake is matched between groups.
Finally and importantly, the majority of studies were carried out on untrained subjects; none employed elite bodybuilders or athletes. There are numerous differences between newbies and experienced lifters, including anabolic responsiveness, the ability to train at higher levels of intensity of effort, the capacity to recruit the full spectrum of muscle fibers, etc. These factors may or may not have an impact on the importance of timing. We simply don’t have enough info to make a determination at this juncture. Moreover, the measures used to assess hypertrophy (i.e. DXA, MRI, CT, etc) have inherent limitations and might not be sensitive enough to show small effects that potentially could be meaningful to competitive athletes. So if you are a highly trained lifter where it is essential to achieve absolute maximal hypertrophy, it makes sense to consume protein as quickly as possible post-workout; doing so certainly won’t hurt and possibly might help, albeit to a small extent.
In closing, I want to say special thanks to Dymatize Nutrition for funding this study. They agreed to provide the grant without any strings. They placed no restrictions on findings; whatever we found, we reported. This truly speaks to the integrity of the company. In my book, they are tops when it comes to nutritional supplementation.
In addition, kudos to the JISSN for publishing a study that runs counter to their position statement on the topic. It’s refreshing to see that journals maintain a commitment to science and reaffirms faith in the peer-review process.
One of the important things about meta-analyses and reviews is that they help to guide the direction of future research. Based on our findings, I am in the process of designing a timing study that should help to fill in the gaps in the literature. Still some things to work out, but I hope to get it underway sometime in 2014.
Moreover, Alan, James and I are currently working on a related meta-analysis that should produce equally impactful results. That’s about all I can say at the moment, but will post as soon as data is available. Stay tuned…
December 4, 2013
Tom Venuto is one of the good guys in the fitness field.
For those who don’t know of his work, Tom is a former natural bodybuilder who turned a passion for getting fit into a passion to help others optimize their fitness goals. He is founder of the popular blog, Burn the Fat, Feed the Muscle and is author of of a number of succesful books. What I admire most about Tom is his balanced, evidence-based approach to exercise and nutrition (as you will know doubt see in the ensuing interview). He is a student of the science as well as an in-the-trenches practitioner. This combination of experience and insight makes him one of the most sought-after practitioners in the country.
I’ve known Tom personally for many years and I’m pleased to have interviewed him about his new book, Burn the Fat, Feed the Muscle: Transform Your Body Forever Using the Secrets of the Leanest People in the World, which will be released next week.
BJS: Thanks so much for consenting to do this interview Tom. I’ve always been impressed with your down-to-earth, scientific approach to fitness. For those not aware of your accomplishments, can you give a brief rundown on your background?
Thank you for the opportunity Brad. I’ve been training for over 30 years nonstop. I got my undergrad degree in exercise science and was a competitive bodybuilder and personal trainer for almost 15 years. Today my full time job is coaching people online through our Burn the Fat community and I’m also fitness writer. I blog at Burn the Fat Blog.com and I’m the author of two books on fat loss including The Body Fat Solution and Burn the Fat, Feed the Muscle.
BJS: Your new book, “Burn the Fat, Feed the Muscle,” was previously published as an e-book. What is different about this book from the previous edition?
The original ebook was first published in 2003. The theme of the new version is the same – the book teaches regular people how to use the nutrition, training and psychology strategies of bodybuilders and other physique athletes – to achieve their own goals. In a decade, a lot of new research emerges and if you stay on top of your game, you grow and evolve as a coach and communicator. I believe it’s important to share the most up to date information and best practices with your readers, in the simplest terms possible to help the most people. So the book has been re-organized, revised and updated with 25% new material including new chapters and a new workout program.
The biggest change I’ve seen over the last decade, which is reflected in what I write, is not a single new diet breakthrough or the discovery of one superior training technique – it’s quite the opposite – it’s how we’ve learned that there is more than one way to skin a cat. Does low carb work? Yes. Does high carb work? Yes. Does 6 meals work? Yes. Does 3 meals work? Yes. Do plant based diets work? Yes. Do meat based diets work? Yes. Does a full body workout work? Yes. Does a body part split routine work? Yes. And yet, this is the hardest thing for the dichotomously-thinking human brain to grasp because it seems contradictory. Fueled by marketing, personal ideologies and the guru culture, most people want to keep believing there’s only one true way. But it doesn’t exist. We need to focus more on the vital few fundamentals that apply to everyone, worry less about the trivial stuff and craft a personalized plan we can live with.
In that spirit, the book stays focused on the same principles and it’s still structured and by the numbers, but it’s more flexible than ever before, allowing for the kind of customization that accommodates an individual’s lifestyle and preferences. It’s also accessible to people who aren’t bodybuilders or scientists. More than ever, Burn the Fat, Feed the Muscle looks at both what the research says and what the real world says – or as you have eloquently said – it’s about the art and the science.
BJS: You discuss how exercise and nutritional routines should be customized based on body type. Can you explain why?
I would describe my philosophy as being more about customization to accommodate everything unique about each individual than about body type in a genotypic classification system sense. Bodybuilders have been fascinated with body types for years – you see somatotyping mentioned in almost all the classic muscle building books – and I do explain those body types in my book too, but I then explain the limitations of the classic Sheldon system, and go beyond it by describing the new phenotypic view about somatotypes.
Mainly, it’s a simple matter of “know thyself.” Know your tendencies biologically and behaviorally, know your goals, know the lifestyle you want to live, and then that helps you customize your workouts and nutrition.
Some of the explanations for body types are so simple, they’re usually overlooked, but becoming conscious of them can be very helpful. For example, what is an ectomorph really, beyond a certain frame and bone structure? Most people think it’s a guy who inherited a really fast metabolism so he burns everything off and never gets fat. “Lucky him” the endmorphs say. But most research says that inter-individual variation in metabolic rate, while it does exist, it’s pretty small. When you look more closely, you see the ectomorph is a person who has extremely high levels of NEAT (non exercise activity thermogenesis) and simply never stops moving. He may also have characteristics that influence him to eat less. Both of these can be genetically influenced. The reverse is true about the endomorph.
I don’t think there’s enough science to put legs under any body typing system in a way that you could just give everyone a quiz and then say, “You’re an X body type so follow program X and you’re a Y body type so follow program Y.” But there are biological and behavioral differences in people that affect how much energy they burn and how much they consume. I also believe there are degrees of carbohydrate intolerance. How much that influences differences in body composition is pretty speculative, but surely some people don’t fare as well on health markers with high carb diets and that’s easy enough for each person to test and prove for themselves. It’s also fair to say that the carb prescription for sedentary people is quite different than it is for athletes. So I think knowing yourself and customizing everything could be seen as a kind of “body typing” I simply don’t stretch it too far beyond that.
BJS: What’s your opinion on calorie counting? Is it really necessary?
Calorie counting is not necessary, but if your goal is fat loss, having a calorie deficit is necessary. The important distinction that a lot of people miss is that there’s a big difference between saying “you don’t have to count calories” and “calories don’t count.” That might sound like the same thing, but it’s not. Lots of people lose weight without counting anything. But that’s because they’ve still achieved a calorie deficit. Whether you count calories and you’re in a deficit or you don’t count calories and you’re in a deficit, the end result is the same – you lose fat.
In a perfect world, we could argue that it really is ideal to follow an eating plan that automatically produces a deficit without you counting calories. It’s like what Brian Wansink said, “The best diet is the one you don’t know you’re on.” The problems are: 1. That’s easier said than done for a lot of people. 2. Many “experts” claim calories don’t matter for weight loss – that it’s only about hormones or eating special foods. Ironically, many diets that prescribe the avoidance of certain “evil fat storing foods” and the frequent consumption of certain “magic fat burning foods” are simply tricking you into eating less. Again, that’s not necessarily a bad thing, except when the “magic” food concept is presented as a gimmick or when “evil” food avoidance becomes dogma and that often turns into real food phobias or even eating disorders.
My approach is to start out building meal plans by the numbers – know your calories and macros – because doing the numbers at least once in your life is an education about nutrition you can’t get any other way. If you’re stuck at a plateau – do it by the numbers as well. You may be shocked at how much you are underestimating caloric intake.
After you’ve done the counting thing for a while, it becomes second nature or “intuitive” if you prefer that word, and you don’t have to do it anymore. But the way I see it, “intuitively” eating the right amount of calories is not something that comes naturally in our modern, temptation-filled, sedentary world today, it’s something you learn and earn through an education and conscious mastery process. Anything else and you’re just guessing, and if you guess right, I would call that luck.
BJS: How important is the macronutrient ratio in optimizing body composition?
Getting a proper balance of protein, carbs and fat is important, but there’s no single macronutrient ratio that’s best. There is nothing wrong with one ratio like 40-30-30, for example, which became very popular through a best-selling diet program. But any reasonably balanced nutrition plan that provides adequate protein, essential fats, fiber and micronutrients, and doesn’t tilt to such extremes that anything essential is pushed out, can be chosen based on personal preference.
I also have no problem setting up meal plans by sensible macronutrient ratios – it makes it easy for me to visualize and conceptualize my plate and food portions. If you use the macro ratio method though, you do have to be conscious that you are using relative figures and one ratio also won’t apply across hypo-, hyper- and iso-caloric meal plans. In a calorie deficit (hypo-caloric) it’s reasonable and prudent to hold protein constant if carb calories are reduced and therefore the ratio of protein goes up though the grams may stay the same.
I would focus especially on hitting the protein goal and checking your quota in grams relative to your body weight, goals and training status, based on the current evidence for optimal protein intakes.
BJS: From a training perspective, how often do you recommend varying the exercises performed?
Short answer: More often for advanced trainees, less often for beginners; more often for bodybuilders seeking hypertrophy and symmetry; less often for pure strength goals. But everyone benefits from exercise variation.
A lot of strength coaches say that your body adapts to the repetition range quicker than an exercise and I think there’s a lot of truth to that. For example, you’re likely to plateau after weeks of squatting sets of 5 or sets of 10 while progressing the weight linearly. But if you implement heavy and light days with different rep brackets, or even three rep brackets, and you vary the intensity of effort too, you’re likely to be able to milk that cycle on that one exercise longer and then continue to get the benefits of one superior exercise.
But with that said, there’s no one exercise that can completely develop every angle, every aspect of every muscle. This is especially important for bodybuilders. A lot of bodybuilders at the advanced level say they feel like they start adapting to an exercise in as little as 3-5 workouts. At the advanced level, I think it makes a lot of sense to change at least some, if not most, of your exercises monthly, sometimes even sooner, and when staying with the same exercise, working the different rep ranges with varying loads as mentioned above. It’s also worth mentioning that boredom is a program killer for a lot of people and mixing it up keeps things interesting.
BJS:Any supplements you feel are particularly worthwhile for muscle building and/or fat loss?
No doubt there are a small handful of supplements with evidence supporting their benefits, some measureable and noticeable. But I’ve never been a big advocate of supplements. Most of them don’t work at all and the few that do are usually terribly oversold, especially in the advertisements.
To be honest, I have a hard time understanding the insatiable desire people seem to have to “take something” considering that supplements are never the make you or break you factor – they’re more like the slight edge. Let me also say that there are very very very big bucks being made in this industry, so always factor that into your buying decisions. Demand strong evidence before buying anything and be extremely careful buying from a company you don’t know anything about. Better: Buy from well-established company you trust, with a human you can contact.
I’ve used creatine before with noticeable results, mainly in workout performance (strength increase), but it doesn’t bother me one bit to train without it. I would use it again and possibly other products if I were in a competitive situation.
I do like protein powder because I use it as food – or as a recipe ingredient. I stir it in my oatmeal, or I mix it with peanut butter and greek yogurt (you gotta try that with chocolate protein – it’s like dessert). And I also appreciate a good smoothie, tasty meal replacement or protein shake recipe, especially if my diet is restricted – It feels like a treat.
BJS: Finally, where can people read more about you and find your book?
My home base on the web right now is my blog – Burn the Fat Blog and our online community where I coach and support our members is Burn the Fat Inner Circle. You can find my on facebook/burnthefat and twitter/tomvenuto. The Burn the Fat Feed the Muscle book is now available in a hardcover and audio version on amazon, barnes and noble and everywhere else books are sold.
December 1, 2013
Finished! Yep, last week I completed data collection for my doctoral dissertation study. It is the first study to compare muscular adaptations (muscle hypertrophy and strength) between bodybuilding- and powerlifting-type routines in well-trained individuals. Preliminary results are really interesting. Can’t get into too much detail at this point but some findings were expected while others were not. The implications with respect to the strength-endurance continuum are significant and will certainly help to further our understanding of how to best structure routines for optimal muscular gains. I’ll have a lot more to say on this over the coming months, including some general observations about inter-individual responses that have important relevance to practical applications. Stay tuned.
In case you missed it, last week I wrote a rebuttal blog post to a journal review article by nutrtional researcher, Dr. John Ivy. In his review, Dr. Ivy challenged a previous paper I co-authored with Alan Aragon on nutrient timing, citing what I consider shaky evidence to support a tenuous position. My post was a point-by-point refutation of this evidence. As noted in my post, I respect Dr. Ivy’s body of work and consider him a fine researcher. In fairness, I emailed him a link to the post and offered the opportunity to write a counterpoint article on my site. As yet I’ve not received a response. If and when he replies, I will post his comments in their entirety.
Finally, here’s the lastest episode of the B&B Connection webcast. In this episode Bret and I discuss the science and art of tempo training. Topics include whether fast or slow lifts are better for strength, power and/or hypertrophy; whether there is a benefit to varying cadence; whether eccentric actions require a different cadence than concentric actions, and; whether “superslow” training has a place in a lfiting routine.
November 24, 2013
Earlier this year, Alan Aragon and I published a review on the efficacy of nutrient timing with respect to enhancing muscular adaptations. The article, titled Nutrient timing revisited: is there a post-exercise anabolic window?, challenged the popular claim that nutrients must be consumed immediately after training to maximize muscular adaptations. For those who want the “consumer friendly” version of the paper, I posted a summary of findings in an earlier blog post; you can read it here.
Recently, Dr. John Ivy took issue with our findings in this review paper published in the American Journal of Lifestyle Medicine. Here is the specific passage where Dr. Ivy references our paper as well as his associated commentary attempting to refute its conclusions:
Whether there is an advantage to nutritional supplementation within the first hour after exercise has been recently challenged. It has been pointed out that the rate of protein synthesis was the same when a supplement composed of 6 g of an essential amino acid (EAA) mixture and 36 g of carbohydrate was provided either 1 or 3 hours after resistance exercise (Rasmussen et al. 2000). It was also reported by Tipton et al. that immediate pre-exercise ingestion of an EAA/carbohydrate solution resulted in a significantly greater and more sustained muscle protein synthesis response compared to its immediate postexercise ingestion. Moreover, the effect of an acute bout of exercise on muscle protein synthesis has been found to last for several days (Chesley et al. 1992; Phillips et al. 1997).
A closer evaluation of these studies, however, shows they do not refute or diminish the importance of supplementation in the first hour postexercise. For one, Fujita et al found that supplementing 1 hour before exercise with an EAA/carbohydrate supplement did not result in enhanced postexercise muscle protein synthesis. Second, Tipton et al later reported no significant difference in net muscle protein synthesis postexercise when 20 g of whey was consumed immediately before versus 1 hour postexercise. Third, when the effect of timing of nutrient supplementation on protein synthesis postexercise is evaluated, the supplement ingested closest in time to the exercise generally has the greatest impact. For example, the increases in muscle protein synthesis reported by Phillips et al at 3, 24, and 48 hours after exercise were 112%, 65%, and 34%, respectively. Finally, there are few studies that actually compare the response of supplementation immediately or within the first 45 minutes postexercise with delaying supplementation for several hours as evaluated by Okamura et al. and Levenhagen et al.. In summary, most acute exercise studies clearly support supplementation soon after exercise for optimal stimulation of protein synthesis and protein accretion.
I’ll start off by saying that I have great professional respect for Dr. Ivy. He is an esteemed professor in the Kinesiology and Health Education department at the University of Texas as well as a renowned nutritional researcher, with a long history of publications in peer-reviewed journals. What’s more, Dr. Ivy literally wrote the textbook on nutrient timing. He has been a staunch proponent of the practice for many years, and frequently lectures on its complexities. But simply because someone is considered an authority on a topic does not mean that he should be above reproach. Science is about evidence. For science to have integrity, we must be willing to challenge popular dogma and test whether it stands up to scrutiny.
In my opinion, the paper by Dr. Ivy falls far short in this regard. Instead, it comes across as a classic example of confirmation bias where evidence is cherry-picked to support a pre-determined opinion. What follows is a point-by-point rebuttal of the points made by Dr. Ivy.
1. First, Fujita et al found that supplementing 1 hour before exercise with an EAA/carbohydrate supplement did not result in enhanced postexercise muscle protein synthesis.
I’ll start with a brief summary of this study: 22 subjects performed a bout of resistance training for the lower body. One group (n=11) consumed a pre-exercise drink containing carbohydrates and protein while the other group (n=11) did not ingest nutrients prior to training. Results showed an increase in post-exercise fractional synthetic rate of ~50% with no significant differences between groups.
On the surface, these findings might seem to support Dr. Ivy’s claim that post-workout nutrition is more imporant than pre-workout nutrition. However, a closer examination reveals otherwise.
First, what Dr. Ivy conveniently failed to point out was this little nugget from the study: “However, the postexercise time course for FSR was different between the two groups in that during exercise the FSR did not decrease below basal values in the EAA + CHO group, and the postexercise increase in FSR was delayed compared with the fasting control group.” Moreover, this is but one study on the topic. Other studies have reported either similar or greater increases in protein synthesis from pre-workout protein consumption versus consuming the same nutrients post-exercise. If you are going to broach the acute response angle, it should be done in the context of the body of literature. At best, an unbiased assessment would say that evidence remains equivocal on the topic.
Perhaps more importantly, Dr. Ivy’s contention here in no way proves the existence of a narrow post-exercise window. Even if post-workout nutrition is more important than pre-workout consumption (which remains debatable), the reference provided does not indicate whether consuming nutrients within 1 hour post-workout would confer any advantages over consuming them say 3 hours post-workout.
2. Second, Tipton et al later reported no significant difference in net muscle protein synthesis postexercise when 20 g of whey was consumed immediately before versus 1 hour postexercise.
I just mentioned this study in Point 1 to counter Dr. Ivy’s claims of a narrow anabolic window of opportunity. In short, the study showed no differences between consuming 20 grams of whey either an hour before or an hour following exercise. How does this support the concept of a narrow anabolic window? If anything, it suggests no benefit to post-exercise nutrient consumption. Dr. Ivy needs to clarify his position here.
3. Third, when the effect of timing of nutrient supplementation on protein synthesis postexercise is evaluated, the supplement ingested closest in time to the exercise generally has the greatest impact. For example, the increases in muscle protein synthesis reported by Phillips et al at 3, 24, and 48 hours after exercise were 112%, 65%, and 34%, respectively.
Again, I am not clear on how the study cited here supports the concept of a narrow post-workout window? The protocol examined protein synthesis at 3, 24, and 48 hours following a bout of resistance training. The response was greater at 3 hours than at 24 or 48 hours. I am at a loss as to the relevance of these findings with respect to immediately consuming nutrients versus delaying consumption for a period of time. Perhaps I’m missing something?
4. Finally, there are few studies that actually compare the response of supplementation immediately or within the first 45 minutes postexercise with delaying supplementation for several hours as evaluated by Okamura et al. and Levenhagen et al..
It’s true that there are a paucity of studies examining the acute response to consuming protein immediately after training versus delaying consumption. My first question thus would be: Given the dearth of such research, how can Dr. Ivy claim there is such overwhelming evidence in favor of nutrient timing if this is indeed what he is using to formulate his opinion?
But let’s overlook this point and explore what research does in fact show. Here Dr. Ivy cites two studies to support his contention. The first one, by Okamura et al. investigated the response to the timed protein feeding after treadmill running in dogs. I’m going to toss this one out as pretty much irrelevant to the topic. It’s an animal study using aerobic training; not exactly indicative of the anabolic response of hard-training lifters. The other study by Levenhagen et al. was a human trial, and it did show that lower body (and whole body) protein synthesis of the legs was increased significantly more when protein was ingested immediately versus 3 hours after exercise. Problem is, the training involved moderate intensity, long duration aerobic exercise. This raises the distinct possibility that results were attributed to greater mitochondrial and/or sarcoplasmic protein fractions as opposed to synthesis of contractile elements. Let’s face it, long duration aerobic exericse is not much of a muscle-building activity. In contrast, Rasmussen et al. investigated the acute impact of protein timing after resistance training–without question a better indicator of synthesis of muscle contractile elements. In this study, no significant differences were seen in the protein synthetic response after consuming nutrients 1 versus 3 hours post-exercise.
5. In summary, most acute exercise studies clearly support supplementation soon after exercise for optimal stimulation of protein synthesis and protein accretion.
Apparently, Dr. Ivy feels he has made a compelling case to substantiate this broad, sweeping statement. As discussed herein, I think not. You be the judge.
By Dr. Ivy’s own admission, there are only a limited number of studies that have investigated the acute response to nutrient timing, and the findings of those that have endeavored to do so are discrepant. If this is indeed the basis for the nutrient timing hypothesis, it’s built on a flimsy house of cards.
Later in his review, Dr. Ivy proceeds to discuss the research looking at chronic muscular adaptations pursuant to nutrient timing. Longitudinal studies would seemingly have greater relevance to practical application, as acute measures of protein synthesis are not necessarily predictive of the long-term hypertrophic responses to resistance training. There actually are a number of studies that have investigated the temporal effects of nutrient provision on muscle hypertrophy following regimented resistive exercise. Alan and I discussed these papers in detail in our review. I won’t rehash the specifics here, but in short some studies show a benefit while others do not. Dr. Ivy curiously chose to extol the virtues of the select few that provided support to his opinion (including a study carried out in rodents and another that inexplicably found no increases in muscle mass when subjects delayed protein consumption a mere two-hours after a training bout over 12 weeks!) while harping on the limitations of those in opposition. Interestingly, he criticizes a study by Verdijk et al. (that failed to show a benefit for nutrient timing) because the dose of protein (20g) was too low while failing to levy the same criticism of a study by Esmarck et al., which showed a benefit to nutrient timing using a protein dose of only 10g! Confirmation bias?
To provide further clarity on the topic, I recently collaborated with Alan and James Krieger to conduct a meta-analysis as to the effects of protein timing on muscular adaptations. We compiled the results of 23 studies on the topic using rigid inclusion/exclusion criteria. In brief, findings showed no differences between immediate versus delayed nutrient consumption with respect to muscle strength or hypertrophy; any benefits from timing were attributed to an increased protein intake as opposed to temporal factors. The meta-analysis will be published soon in the Journal of the International Society of Sports Nutrition. I’ll have lots more to say about the study once it is available in print.
For the record, Alan and I limited the focus of Nutrient timing revisited: is there a post-exercise anabolic window? to hypertrophic adaptations. As we pointed out, there are certainly other areas where timing of meals can be a viable strategy, particularly for athletes who need to train or perform multiple times in the same day. What’s more, there is compelling evidence that resistance exercise sensitizes muscle to the anabolic effects of food. Thus, there is a benefit to consuming nutrients, and protein in particular, following a resistance training bout. The caveat is that you don’t necessarily need to worry about scarfing down nutrients the moment you finish lifting. Our findings suggest that the “window of opportunity” is probably around 4-6 hours following resistance exercise, with the specifics of timing dependent on when you ate your last meal prior to training. Delaying nutrient consumption for many hours after training would seem to be unwise.
In closing, there certainly is a need for more studies on the topic. I am open to changing my opinion should compelling evidence come to light. But based on our extensive review of literature, research supporting a narrow anabolic window is currently lacking.
If Dr. Ivy wishes to debate the topic, I welcome him to rebut my comments. I will gladly publish his response on my blog in its entirety without editing. Let’s put all the information out there so that the general public can form an educated opinion. After all, that is how science ultimately progresses and thrives.