What is the post workout anabolic window?
It’s a theory that there is a period of time (30′-45′) after intense exercise in which your body needs to be filled with nutrients to stop muscle catabolism.
The theory says that your workout optimizes your body’s ability to store the nutrients as muscle instead of fat.
After training, protein synthesis is elevated so you have to take eat some protein and fill your body with amino acids.
Based on that theory you must eat a meal with protein and “quick release carbs” within one hour after your workout.
Otherwise, you won’t build muscle, your training will be wasted or you might also get smaller and lose size after time.
Especially newbies fall in the trap of believing the myth of the post workout anabolic window.
This article will challenge conventional thinking and classic brosciene advice based on scientific facts which show that there is no anabolic window.
Will You Really Lose Muscle If You Don’t Eat After Your Workout?
(Is the anabolic window of opportunity real or not?)
The hypothesis of the anabolic window is based on a theory which says that: After lifting weights you have depleted glycogen stores and damaged muscles.
That’s why you have to eat carbs to replenish body glycogen and provide your body with energy. You also have to drink protein to repair the damaged muscles.
Moreover, muscle protein synthesis is increased right after resistance training and that’s why you have to eat protein immediately after your workout right?
This statement is true.
But according to a study conducted by Department of Kinesiology, McMaster University, Hamilton, Ontario protein synthesis is elevated 24 hours after heavy resistance training and then decreases.
“Muscle Protein Synthesis is elevated in humans by 50% at 4 hours following a bout of heavy resistance training, and by 109% at 24 hours following training. It is concluded that following a bout of heavy resistance training, muscle protein synthesis increases rapidly, is more than double at 24 hours, and thereafter declines rapidly so that at 36 hours it has almost returned to baseline”(link)
Based on that the anabolic window of opportunity where you have to drink your post workout shake or eat a meal is 24 hours after your workout.
There is no need to break the speed limit while driving home to drink your protein shake 30 minutes after your workout.
How Protein Synthesis & Breakdown Rate is Related to Building Muscle
Your body builds muscle when the protein synthesis rate outweighs protein breakdown rate.
The theory behind the anabolic window suggests that you should eat right after your workout to avoid muscle protein breakdown.
Because of that you need to eat protein and carbs to spike insulin and slow down your muscle protein breakdown rate.
This sounds legit, but is there a need to be in a hurry and being forced to have a post workout meal immediately after working out? Or is there a bigger window available?
In a study conducted by Shriners Burns Institute,Texas, USA, eight untrained volunteers were examined after resistance training.
Resistance exercise resulted in significant increases in muscle protein synthesis rate at all times after a workout and more specifically: 112% increase after 3 hours, 65% after 24 hours and 34% after 48 hours.
Muscle protein breakdown rate was also increased by exercise at 3 hours(31%) and 18% at 24 hours post exercise but returned to resting levels by 48 h.
The conclusion was that muscle net protein balance is increased after training and persists for up to 48 hours after exercising. (link)
This means that you have a time period of at least 3 hours after working out that your body is in a state where it builds muscle rather than breaking it down.
You Don’t Necessarily Need a Post Workout Shake. Protein Timing Is Irrelevant with Building Muscle.
Whether you eat the same amount of protein during the day or right after your workouts you won’t see significant differences. This was proved by a study from the Journal of International Society of Sports Nutrition (link).
In particular, what truly matters is the overall protein intake.
You can’t rely on the post workout anabolic window to deliver maximum muscle gains, but you should rely on how much protein you consume throughout the day as this makes the biggest ROI for your time and money.(link)
Then comes another study (link) which found out that: “the time of protein-supplement ingestion in resistance-trained athletes during a 10-week training program does not provide any added benefit to strength, power, or body-composition changes.”
So the point is that the exact timing of your post workout protein doesn’t matter as long as you get the necessary amount during the day.
But, this doesn’t mean that timing your nutrients is useless as in cases like fasted training it’s better to eat right after your workout.
Should You Eat After Your Workout If You Train Fasted?
There is no need to drink a post-workout shake unless you are training fasted.
In that case you should eat a meal after working out because muscle protein breakdown rate is significantly heightened post-workout. (link)
Training fasted means that you haven’t eaten a meal for many hours before training. For instance, if you workout in the morning before eating breakfast.
During fasted exercise, there is an increase in muscle protein breakdown. Thus, it seems logical to provide your body with the essential nutrients right after your training session.
The ideal would be a combination of protein and carbohydrates because this promotes muscle protein synthesis and reduces proteolysis which turns your body from a catabolic state to anabolic.
When you apply this tactic over a long time period it can lead to an increased rate of muscle gains.
But even if you train fasted you don’t have to be obsessed with the post workout anabolic window. Try to eat a meal or your post workout supplement as fast as possible, but don’t hurry to get back home in 30 minutes to eat.
So How Much Should I Eat?
Based on the same study from the Journal of International Society of Sports Nutrition it is believed that a high protein dose at 0,4-0,5 g/kg of LBM at both pre and post exercise is a relatively safe guideline based on the current scientific evidence.
For example, someone with LBM of 80kg should get about 30-40 gram of protein in BOTH the pre and post workout meal.
According to the researchers this is the ideal intake to maximize muscle growth.
Exceeding this amount wouldn’t give more benefits while neglecting pre and post workout nutrition completely wouldn’t help in maximizing the anabolic response.
What About Carbohydrates? Do They Really Help After a Workout?
Just like protein intake, carbohydrate dosage and timing is another thing which isn’t clearly explained from recent scientific research.
Carbohydrates are recommended for increasing your energy and endurance after an exhausting workout session.
However, co-ingestion of carbs and protein after exercising is challenged by a study (link) which found that adding carbohydrate to a dose of casein after working out doesn’t provide any benefits regarding increased muscle growth comparing to a post-workout meal only with protein.
According to Menno: if you have received ample protein, then carbohydrates do not further stimulate protein synthesis.
If you can’t or simply don’t want to eat carbs in your post-workout meal then you don’t have to. Just like with protein intake, it’s the overall carbohydrate intake throughout the day that matters more than the amount of carbs that you consume after your workout.
As long as you meet your daily macronutrient intake you don’t necessarily need to eat carbs in your post workout meal.
However, if you are an athlete who will train again in 3-4 hours, then you should better eat some carbs to re-fill your body’s energy reservoir.
Marketing, Convenience & Personal Schedules
So if all this research indicates that the anabolic window of opportunity doesn’t exist, why do people believe it?
Here comes the marketing.
How will supplements be sold if there is no motive for people to buy these supplements?
The post anabolic window is an incentive that persuades fitness enthusiasts to buy a variety of supplements to help them recover and build muscle faster.
The post anabolic window is a marketing scheme that companies took advantage of to sell us product like whey protein, weight gainers, or hydrolyzed whey which is said to be absorbed faster.
Check this article from my friend Ludvig to learn more about how marketing is used by companies to sell us things.
“Oh man, hydrolyzed whey is absorbed faster?
Let’s drink a shake of that to take advantage of the post workout anabolic window!”
I don’t say that these supplements are bad.
I drink whey protein smoothies here and there and love them. But I am not obsessed with carrying a 5lbs whey with me in the gym to drink a post workout shaker 5 minutes after my workout.
Yes, I know people who do that thing.
If you haven’t trained fasted your body has already some nutrients to digest from your previous meal.
The process of digestion takes some time – so if you have eaten 1-4 hours before training then your body still has nutrients that can use.
As a result, you don’t need to eat immediately after training.
Of course, if it’s convenient for you to eat after working out then do it.
The length of the feeding window before and after exercising is totally flexible. Nutrition timing should depend on your personal schedule.
If it fits your schedule and lifestyle, then you could shift your training sessions closer to your pre or post workout meals.
Conclusion & Key Points On The Existence Of The Post Workout Anabolic Window
I know that’s a lot of information to digest so let’s sum up the main points:
1. You don’t have to worry about the existence of a short-term feeding window after your workout. You are free to feel relaxed and eat your post-workout meal when your schedule allows it.
2. Overall protein intake during the day plays a more significant role in building muscle than the time you eat the protein.
3. If you are training fasted then you should eat your post workout meal as soon as possible, but again you don’t need to be in a hurry.
4. If you have received ample protein after in your post workout meal then carbohydrates do not further stimulate protein synthesis.
5. Nutrition timing should fit your personal schedule. You can shift your training session toward your post or pre workout meal based on your lifestyle.
PS: Do you eat right after your workout?
Let me know in the comments and then SHARE this post with your friends on social media to help them understand the anabolic window myth!