anabolic window

Today, we’re looking at the question, do you really need to be taking a protein shake after training sessions? To answer this, we really need to look at the concept of the post-workout anabolic window.

What is the Anabolic Window?

For those who don’t know, the anabolic window is thought to be a short time period, generally 30-60 minutes immediately post training. The idea is that if you induce protein, it will ramp up muscle repair and new, lean muscle development. If you miss this window, then it’s thought that you’ve completely missed out on the opportunity.

There are generally two schools of thought when it comes to the anabolic window. Camp #1 is all for the anabolic window, believing this is the most important time for nutrient delivery and it’s only open for a small amount of time immediately after training. Camp #2 believes that it’s a myth and doesn’t exist, generally believing that Camp #1 is basing everything on bro science or old science. The truth of the matter? It actually lies somewhere in between these two opinions.

The Truth About the Anabolic Window

Multiple studies that supported post-training protein ingestion concluded that it is of utmost importance and responsible for the body’s shift into an anabolic state. These support the existence of an anabolic window. However, a meta-analysis was conducted on the dozens of previous reputable studies. While this meta-analysis recognized that a hypertrophy effect was present from subjects who ingested post-workout protein, it actually concluded that the lean muscle development differences could be explained by the fact that the post-workout supplementation simply increased total daily protein intake. The specific timing was not important.

What Happens to Your Body Post Workout

Before you take your protein shaker out of your gym bag, it’s important to understand what happens to our body post training. In particular, your muscle protein synthesis. Both camps, for and against the anabolic window, agree that when you work out and stress your muscles significantly, you up regulate the process of muscle protein synthesis. This allows your body to combine amino acids into new protein, aka new lean muscle tissue.

It’s during this time of muscle protein synthesis elevation that protein consumption will have a positive and supporting effect. But how long are these muscle protein synthesis levels elevated? And how long do you have to ingest protein to take advantage of the already elevated levels?

One particular study showed elevated protein synthesis levels up to 48 hours post training, meaning any protein ingested within that 48 hours will support muscle protein synthesis. This is a fair bit longer than the original 30- to 60-minute anabolic window that used to be the belief. However, the more trained an individual is, the less time these elevated muscle protein synthesis levels are present. Beginners can experience elevated muscle protein synthesis levels up to 48 hours, meaning ingesting protein anywhere in this time frame will have an enhanced effect. In contrast, trained athletes’ elevated muscle protein synthesis window is much, much shorter. How long do you have? Well, I have yet to see a study supporting any less than 16 hours of elevated levels. So while much shorter than that 48 hours, it’s still much longer than the original 30- to 60-minute window.

The Muscle Protein Synthesis Spike

So should you be taking the protein powder out of your gym bag, back on the shelf and throwing the shaker bottle in the bottom drawer? In my opinion, most definitely not. What I take into account for all my clients and make sure that they take advantage of is the post-workout, muscle protein synthesis spike. This is present whether you’re a beginner or not.

In the same study, it was evident that 0-3 hours after training is the highest spike in muscle protein synthesis. If you’re trying to maximize your efforts, then ingesting protein during the spike is still the best practice to support your muscle protein synthesis. Be aware of digestion though. Waiting two hours after training to cook chicken or a steak sounds great. They’re both a solid source of protein. But you need to take into account the digestion speed. While you’ll still be in an elevated muscle protein synthesis state, you’ll miss the spike. It’s arguably a minimal difference, but it’s a difference nonetheless. Pick a fast-digesting protein source. This is where an isolate protein or a whey protein is of the most benefit.

Now to really take advantage of each post-workout spike, I recommend that my clients take a whey or isolate protein immediately after training, right at the beginning of the three-hour spike. Then, one and a half hours later, still in the spike, I have them eat a real protein source meal, such as chicken breast or white fish, a carbohydrate, but no fats. It will take your body longer to digest this second meal than the protein shake, but you still want your body to digest the second meal and uptake the nutrients as fast as it can while still within the spike. Having fats in the meal will slow the digestion down.

Remember, while this timing effect is minimal in the big scheme of things, it is what’s optimal. Consistently followed day after day, month after month, the positive effects of taking advantage of the muscle protein synthesis spike will add up over time.

In conclusion, while the 30- to 60-minute window theory is done, what should be recognized is the up regulated levels of protein synthesis present after training. The only way you would completely miss out on these elevated levels is not eating for 16-48 hours. Recognize that a muscle protein synthesis spike is there to be taken advantage of by those looking at every angle to get the edge and maximize their efforts.

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