Tyler Robbins Fitness

B.Sc. Biochemistry, Certified Strength and Conditioning Specialist (CSCS), Certified CrossFit Trainer (CCFT/CF-L3), USA Weightlifting Level 1

Filtering by Tag: Anabolic Window

>12h Anabolic Window....Bro

Readers of my blog know that I am not a big fan of broscience. Sure, sometimes broscience can be pretty bang-on with its claims, but for the most part evidential science tells us otherwise.

One of the biggest myths or misconceptions that I hear all the time surrounds the supposed post workout 1-hour anaobolic window. This is certainly one of these things that since it hear it repeated so often, it just seems to be truth. In actuality, and I love Brad Schoenfeld's take on this, rather than calling it a post workout anabolic window, it should probably be called the post workout anabolic barn door.

A recent study in the American Journal of Physiology looked at just this idea:

Pre-sleep protein ingestion does not compromise the muscle protein synthetic response to protein ingested the following morning


Protein ingestion before sleep augments post-exercise muscle protein synthesis during overnight recovery. Purpose: It is unknown whether post-exercise and pre-sleep protein consumption modulates post-prandial protein handling and myofibrillar protein synthetic responses the following morning. Sixteen healthy young (24±1 y) men performed unilateral resistance-type exercise (contralateral leg acting as a resting control) at 20:00 h. Participants ingested 20 g protein immediately after exercise plus 60 g protein pre-sleep (PRO group; n=8) or equivalent boluses of carbohydrate (CON; n=8). The subsequent morning participants received primed-continuous infusions of L-[ring-2H5]phenylalanine and L-[1-13C]leucine combined with ingestion of 20 g intrinsically L-[1-13C]phenylalanine and L-[1-13C]leucine labelled protein to assess postprandial protein handling and myofibrillar protein synthesis in the rested and exercised leg in CON and PRO. Exercise increased post-absorptive myofibrillar protein synthesis rates the subsequent day (P<0.001), with no differences between treatments. Protein ingested in the morning increased myofibrillar protein synthesis in both the exercised- and rested-leg (P<0.01), with no differences between treatments. Myofibrillar protein bound L-[1-13C]phenylalanine enrichments were greater in the exercised (0.016±0.002 and 0.015±0.002 MPE in CON and PRO, respectively) versus rested (0.010±0.002 and 0.009±0.002 MPE in CON and PRO, respectively) leg (P<0.05), with no differences between treatments (P>0.05). The additive effects of resistance-type exercise and protein ingestion on myofibrillar protein synthesis persist for >12 h after exercise and are not modulated by protein consumption during acute post-exercise recovery. This work provides evidence of an extended window of opportunity where pre-sleep protein supplementation can be an effective nutrient timing strategy to optimize skeletal muscle reconditioning.

This research is indicating that the timing of your protein ingestion probably isn't as important as you once thought, and the speed at which you down your shake isn't going to make or break your gainz. Instead, and something that I repeat to my clients time and time again, is focus on hitting your protein goals between the time you wake up and the time you go to bed - around 1g/lb. bodyweight. On top of that, and something that this study is suggesting, is that having some circulating protein in your system during the hours you are sleeping can be beneficial as well.

I would postulate that since human growth hormone spikes when you are sleeping, it would be extremely beneficial for your body to have some readily-available amino acids for tissue growth, repair, and regeneration during that time. I personally wouldn't worry about the absorption rate of various types of protein - casein vs. whey, for example, since the rate of digestion and then absorption and utilization are quite different. The rate-limiting step of protein absorption is based on the protein transports that carry the broken down amino acids from the intestines and eventually end up at the desired site of growth and repair (muscle tissue, for example).

The Great Protein Timing Debacle

"You need to consume some protein within an hour after your workout!"

"There is something called an 'anabolic window' when your body is primed for protein intake!"

"Stay away from fats and casein protein, they slow digestion. You need the fastest-digesting whey protein you can find."

Etcetera, etcetera, etcetera.

If you exercise, have either looked into supplements before, have talked to a supplement store salesperson, or even carried on a conversation with someone about health and fitness then you have probably heard one of these statements, or least something along the same lines.

Basically, what we are lead to believe is that you will lose any and all of your potential gains if you don't ingest some protein within an hour after your workout. I think this sentiment has become something that is repeated so often that it must be true!

It just makes so much sense, right? You are working hard during your workout, your muscles are burning, your muscles are pumped, you feel fatigued, it must mean that your muscle tissue is damaged and ready to start rebuilding. Unless of course you don't eat some protein within an hour following your workout, in that case, your muscles are going to....shrivel up and decay!

That's ok, because all you need to do is invest in some of that fast-digesting whey protein. Oh, and definitely don't forget your BCAAs to take prior to your workout, especially when working out in a fasted state, you wouldn't want your muscles to shrivel up during your workout. Stack on this supplement, and that supplement, and the next thing you know, you are dropping hundreds of dollars a month just so your muscles don't waste away and you can build the biggest, most badass muscles around.

I have actually already written about why I think BCAAs are more hype than not, so head on over there to read about that.

Here are the 2 main problems I have with the current reasoning behind post-workout protein consumption:

  1. The theory is that consuming protein immediately following a workout is best for muscle protein synthesis (MPS) due to micro tears or trauma caused by resistance training. In actuality, MPS takes place over a longer period of time. In fact, the net intake of protein during a day is far more important than how much or when protein is taken in following a workout.

  2. Regardless of how fast your protein digests (whey vs. casein, for example), your muscles benefit more from readily-available amino acids in your bloodstream throughout the day rather than how quickly the protein can be absorbed.

So what can we learn and summarize from not only this article, but from the topic of nutrient timing?

  • If you are working out (resistance training) during a fasted state, it is beneficial for you to consume some protein as soon as you can following your workout. If, however, you have eaten some protein during the day and are working out in the evening, for example, then you have a greater "window" of opportunity (about 6 hours) in which it is beneficial for you to consume protein.
  • Protein intake should be spread out throughout your day. A "steady drip" of amino acids in your bloodstream give your body and muscle tissues the tools required to rebuild.
  • Having said that, regardless of how quickly protein digests and/or is absorbed into the bloodstream, muscle protein synthesis is a very slow process, generally lasting for a couple of days so the "speed" at which you can get your protein into your bloodstream is of little value. Your intestines absorb close to 95% of your ingested protein and can actually 'slow' the absorption rate in order to ensure your use as much as you can from the food you ate.
  • Ingesting protein following or even prior to a workout should not hinder your results by any means, in fact, it may hold some benefits. However one should not place too much emphasis on when they consume their protein nor should they listen to the hype about how fast a protein digests and/or absorbs.
  • Glycogen depletion is still a very relevant issue, and if you are an athlete who wishes to either perform for long periods of time, multiple times in the same day, or even perform on back-to-back days, then you should consider immediate glycogen replenishment after a training session or competition to perform at your very best.

How important is protein timing?


Short answer: It isn't. At least according to a study from Brad Schoenfeld.

I know, I know, I keep ruining some people's common misconceptions. Just the other day I wrote about why BCAA's are a waste of money. Today, I am going to discuss the fact that when you ingest your protein has little to do with your results.


Protein timing is a popular dietary strategy designed to optimize the adaptive response to exercise. The strategy involves consuming protein in and around a training session in an effort to facilitate muscular repair and remodeling, and thereby enhance post-exercise strength- and hypertrophy-related adaptations. Despite the appar- ent biological plausibility of the strategy, however, the effectiveness of protein timing in chronic training studies has been decidedly mixed. The purpose of this paper therefore was to conduct a multi-level meta-regression of ran- domized controlled trials to determine whether protein timing is a viable strategy for enhancing post-exercise mus- cular adaptations. The strength analysis comprised 478 subjects and 96 ESs, nested within 41 treatment or control groups and 20 studies. The hypertrophy analysis comprised 525 subjects and 132 ESs, nested with 47 treatment or control groups and 23 studies. A simple pooled analysis of protein timing without controlling for covariates showed a small to moderate effect on muscle hypertrophy with no significant effect found on muscle strength. In the full meta-regression model controlling for all covariates, however, no significant differences were found between treat- ment and control for strength or hypertrophy. The reduced model was not significantly different from the full model for either strength or hypertrophy. With respect to hypertrophy, total protein intake was the strongest pre- dictor of ES magnitude. These results refute the commonly held belief that the timing of protein intake in and around a training session is critical to muscular adaptations and indicate that consuming adequate protein in com- bination with resistance exercise is the key factor for maximizing muscle protein accretion. 

I have always approached exercise and health science with the same mindset, that the human body is far more complex than what most people give it credit for, and that the level of efficiency in which our bodies conduct day to day activities is incredible.

Case in point, I believe that far too many people have this mindset that our bodies, or more specifically, our muscles just break down or deteriorate due to extreme bouts of exercise. Sure, during extreme cases, our bodies become anabolic in nature (the breakdown of muscle tissue) for energy production. This occurs during times of famine or long bouts of exercise without proper nutrition.

Having said all of that, regardless of how intense your workout is, chances are, your body is has more than enough stored energy to complete the task at hand.

Well what about all this talk about muscle tearing and tissue breakdown during resistance training?

Once again, yes, resistance training causes micro trauma, tears, and tissue breakdown during resistance training, however that does not mean that those muscle cells just shrivel up and die if you do not drink Muscle Milk within one hour following your workout.

There seems to be some evidential truth about carbohydrate ingestion to replenish spent glycogen stores immediately following an intense bout of exercise, but even then, it is only important if you are planning on continuing on with even more intense exercise or life events later that day. If you have a casual or even slightly difficult day, physically that is, your regular well-rounded diet throughout the day will aid in glycogen replenishment.

Enough about that, however, back to protein synthesis.

So the common misconception is that after an extreme bout of resistance training, your body should be blasted with essential amino acids, found in your common protein shake immediately following exercise. There are even phrases thrown around about like a "1-Hour Anabolic Window."

The fact of the matter is, your body does not complete a difficult resistance training routine and then immediately resort to digesting and breaking down its own muscle tissue due to damages caused by said resistance training. Instead, your body recognizes the damage done to the muscle tissue, and focuses on repairing it throughout the day, assuming you are ingesting enough protein to meet the demands. This study found that your net protein intake was more important than the timing of it.

Basically, don't beat yourself up if you have a busy schedule, do your workout, and then can't get your hands on some protein until a few hours later. Also don't be so focused on special supplements that advertise "Enhanced Recovery" with large amounts of protein in them.

For very active individuals, especially those who resistance train more than a few times per week should aim for at least 0.8-1g of protein for every pound of body weight. So, for myself, I currently weight right around 183lbs, so I should be aiming for at least 146-183g of protein on a daily basis (when training) to prevent muscle loss (catabolism) and to promote muscle growth (anabolism).

Whole, animal protein sources should aways take precedence (whey, meats, dairy, etc.). Vegetarians can absolutely meet their protein needs, but need to compliment plant sources due to plant proteins being incomplete - lacking all of the essential amino acids. Aim to get as much of your daily protein from food first, then supplement as an accessory.