The Anabolic Window Debate
by Evelyn Valdez·
One of the oldest post-workout methods that bodybuilders and gym-goers swore by was the anabolic window. It refers to a window of time after intense exercise when the body's glycogen stores are low. This was believed to be a window of opportunity to consume quick release protein, like whey protein powder, or high glycemic index carbohydrates, like dextrose, immediately after a workout to provide the muscle tissue with the much-needed nutrients it needs to recover and increase muscle size. But for maximum results, this window of opportunity is short and only lasts around 30 minutes.
To anyone strength training this seemed like it made perfect sense and many jumped at that idea in order to maximize their efforts and increase serious muscle strength. But recent research suggests that the post-workout anabolic window is not as perfect as we thought...
This concept isn't all bad, there is some truth to it, which is why so many people still like to have a protein shake or post-workout snack after an intense training session. So if the entire anabolic window thing isn't 100% accurate, then what about it is? What is the optimal way to refuel for post-workout recovery?
Don't worry, we are going to cover everything about the anabolic window so you can decide whether your training can benefit from it... And if it's not, we have some tips on what to do instead!
Breaking down the anabolic window myths
The reason this concept gained traction in the first place has to do with how the body reacts after training. After weight training or doing any form of high-intensity training, the muscle fibers are damaged and the glycogen stores within those muscle tissues are depleted - This is true. So the idea was that consuming much-needed nutrients (protein and fast-acting carbs) immediately after a workout could help you take advantage of the body's energy depleted state and give the muscle tissue what it needs to recover effectively. The fast-acting carbs also help jack up insulin levels helping to shuttle nutrients into the muscle cells. Doing this was said to increase muscle protein synthesis, refill muscle glycogen stores, and maximize strength and muscle growth. This all sounds amazing, but it's not exactly how it works...
So the idea is to consume fast-acting carbs to accelerate the replacement of glycogen, your body's preferred source for fuel. Although muscle glycogen is synthesized rapidly if you consume carbs right after a workout as opposed to hours later, research shows that glycogen synthesis after exercise is not important as long as you're meeting your daily carb intake.  Meaning just making sure to eat enough good carbs throughout the day, not just during that 30-minute window after training, will improve glycogen synthesis.
Another reason people may consume a post-workout shake filled with carbs and protein is to increase muscle protein synthesis to build muscle tissue. It's true that in order to build muscle, protein synthesis needs to be higher than the rate at which muscle protein breakdown occurs, but studies show that post-workout nutrition does not help with that. Two top bodybuilding nutrition researchers wrote an in-depth review concluding that after analyzing and comparing relevant studies, there is no conclusive evidence that shows consuming protein or carbohydrates after a workout increases muscle protein synthesis or the rate at which muscle tissue recovers.
If there’s no conclusive evidence that says it helps with muscle-building and building strength then do you even need to immediately have post-workout protein or carbs? Let’s find out...
Should you give up your post-workout ways?
It’s up to you! Post-workout nutrition is important, but consuming protein and/or carbs during the short anabolic window won't maximize your gains like you originally believed. Although, there is one situation when the anabolic window might ring some truth... Training in a fasted state.
Studies show that fasted workouts, meaning training before eating breakfast or fasting for 12+ hours, does significantly raise muscle protein breakdown post-exercise. In this case, if you're working out in the morning before breakfast then you should aim to have either a post-workout meal within an hour or so after your workout or a protein shake with some fast-digesting carbs. The reason post-workout nutrition is more important after fasting is because fasting naturally puts your body into a catabolic state, a breakdown state where stored nutrients are put to use. Meaning once you're in that state your body will start breaking down glycogen for energy in order to tap into another source to use for energy - Fat. The idea behind fasted workouts is to deplete the glycogen stores (glucose) near empty in order to tap into fat stores during exercise. Basically, fasted workouts results in the body's glycogen stores being depleted and increases the rate of protein breakdown. So in this case a quick protein or carbohydrate intake is necessary for optimal recovery.
What to do instead
Unless you're working out in the early morning in a fasted state, you don't need to rush to have a post-workout meal. Instead, calculate and track your macronutrients to focus on hitting your daily fat, protein, and carb intake evenly throughout the day. Tracking your macros is an easy way to make sure that you're eating enough carbs to fuel your workouts, protein to keep muscle protein synthesis high, and other nutrients like fats, vitamins, minerals that help build and repair muscle tissue. So instead of placing so much focus on ingesting a protein supplement only after your workout, focus on making sure to get enough protein throughout your day. The same goes for carbs!
If you want to take it a step further to help with your efforts in building muscle try nutrient timing. There's no short time window frame like with the anabolic window, instead, it involves timing your snacks or meals (make sure they're protein-rich) around your workouts to make sure your body has the important nutrients for energy and recovery. Here's how it works...
Consume a meal or snack, consisting of protein and carbs, between 2-3 hours before your workout. If you don't have time for that, consider taking a protein supplement like a protein shake an hour before your workout. Having a mix of protein and carbs will provide your body with the energy it needs to complete the workout and since protein is digested at a slow rate, a sustained release of amino acids will be in the bloodstream during your workout and even after. By doing this you no longer need to quickly refuel after training. Instead, you have a 2-4 hour window of time to have a post-workout meal with a mix of protein, carbs, and fats. This will help provide the body with essential nutrients and a continued release of amino acids into the blood to aid in recovery. And on the days you're too busy or just need a little boost or help to meet your nutrient intake, consider taking a supplement, like protein powder, creatine, EAAs essential amino acids, or branched chain amino acids (BCAAs). Supplementation isn't a replacement for a healthy diet, it's a way to help improve your training and recovery by giving you exact doses of the nutrients your body needs. Again, only use these when you really need them!
The bottom line is, post-workout nutrition is important, but not in terms of the anabolic window. You don't need a quick carb or protein ingestion after intense training unless it was done in a fasted state. When it comes to building muscle mass, focus on consuming the necessary macronutrients spread evenly throughout the day. It is ideal to eat a few hours before and after your workout, but it's not the end of the world if you can't as long as you hit your daily protein intake along with other essential nutrients! As an extra tip, eat foods that help with muscle recovery to reduce muscle soreness. Don't know what they are? Here's our list of the 10 best foods for muscle recovery!