February 15, 2013

Nutrient Timing Revisited: The Anabolic Window of Opportunity

I recently co-authored a review article with my good friend and colleague Alan Aragon titled, “Nutrient Timing Revisited: Is there a post-exercise anabolic window?” I’m happy to say the article was published in the prestigious Journal of the International Society of Sports Nutrition and has received a lot of favorable attention. Here are the highlights:

1) Nutrient timing can be a beneficial strategy for maximizing muscular gains, but the “window of opportunity” is not necessarily as narrow as often believed.

2) Provided that a protein-rich meal is consumed within about 3-4 hours prior to a workout (or possibly even longer, depending on the size of the meal), you don’t have to stress about chowing down a post-workout meal as soon as you finish training. For those who train partially or fully fasted, on the other hand, consuming protein immediately post-workout becomes increasingly more important to promote anaoblism.

2) Although research is somewhat equivocal, it seems prudent to consume high-quality protein (at a dose of ~0.4-0.5 g/kg of lean body mass) both pre- and post-exercise within about 4-6 hours of each other depending on meal size.

3) Contrary to popular belief, consuming post-exercise carbohydrate does not meaningfully enhance anabolism. Moreover, unless you are performing two-a-day workouts involving the same muscle group(s), glycogen replenishment will not be a limiting factor in those who consume sufficient carbohydrate over the course of a given day. So from a muscle-building standpoint, just focus on meeting your daily carb requirement as opposed to worrying about timing issues.

One of the most surprising aspects of writing this paper was the lack of clarity in the current body of research. Alan and I reviewed every direct study conducted on the subject. Not only were results of these studies highly conflicting, but most had confounding issues that obscured the ability to tease out the impact of the effects of consuming nutrients post-workout. I am planning a study in my lab that addresses the gaps in the literature. Hope to begin data collection in the near future. Stay tuned!

In case you want to delve into the heavy science on the topic, here is a link to a PDF of the article:

Nutrient Timing Revisited: Is there a post-exercise anabolic window?




  1. Congrats once again, Brad!

    This topic is a good example of how you have to analyze the literature than just read the abstract of one or two studies and jump to recommendations. And this is what they call an the evidence based approach!

    Comment by Anoop — February 18, 2013 @ 5:39 pm

  2. Excellent point Anoop. Always appreciate your insightful comments 🙂


    Comment by Brad — February 20, 2013 @ 7:39 am

  3. […] er hovedmomentene , hentet fra Brad sin blogg men noe […]

    Pingback by Det anabole vinduet - hva sier forskning? - MyRevolution — February 24, 2013 @ 4:32 am

  4. Quoting from your new book.”One of the primary goals after exercise is to replenish glycogen stores. Because glucose is depleted during training, your muscles and liver are literally starved for carbohydrate.”
    So ignore this and give emphasis on the latestly published stuff?

    Comment by Michael — August 18, 2013 @ 9:17 pm

  5. Correct, Michael. My views have changed over the past couple of years with respect to the post-exercise anabolic window. Certainly there is no downside to consuming nutrients immediately after training, but recent research shows that the window is not as narrow as once believed. Focus on the peri-workout window as described in this post.



    Comment by Brad — August 19, 2013 @ 7:06 am

  6. […] can read Brad’s online article on this topic here or if you’re a real muscle geek – read the full paper here […]

    Pingback by How Soon After a Workout Must I Consume Protein? | Fitness Baron - Build Muscle, Burn Fat and Look Great — September 13, 2013 @ 1:45 pm

  7. […] 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. […]

    Pingback by » Nutrient Timing: Don’t Let Confirmation Bias Stand in the Way of Science — November 24, 2013 @ 8:32 am

  8. […] As many of you know, an area of research that I’ve recently been pursuing is the effects of protein timing on muscle strength and hypertrophy. In 2013 I collaborated with my good friend and colleague Alan Aragon to publish a review on the topic titled, Nutrient Timing Revisited: is there a post-exercise anabolic window?. In short, our review concluded that while muscle is sensitized to anabolism in the post-workout period, current evidence does not seem to support the existence of a narrow “window of opportunity.” I discussed the practical implications of the review in a previous blog post. […]

    Pingback by » Protein Timing Revisited: The Importance of Objectivity in Drawing Evidence-Based Conclusions — August 2, 2014 @ 1:45 pm

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