Best time to drink protein shakes? Is anabolic window real?

By Ire | Calories

Mar 17

It has been argued that best time to drink protein shake is just after the workout. There is this idea that you have 30 minutes right after the workout to consume your magical drink. Should you not take advantage of that, your gains will suffer!

But is it real? Does anabolic window really exist. And if not, what is the best time to drink protein shake?

Protein shakes does not equal magic potions

Protein shakes are not going to give you any different effect as opposed to high protein meal. Protein is not something you only get in magical powder tub you bought off Amazon. It is also found in food!

Therefore, I will be restating the question:

What is the best time to consume protein for maximal muscle growth?


Role of protein

Calories consumed by the food divide into three parts:
1. Protein
2. Carbohydrates
3. Fat

Each of those has different structures and functions!

Protein has a structure divided by thousands of units called Amino Acids. One of their function is tissue growth. Therefore, it is tightly related to muscle building.

Bearded man squatting in a squat rack, smiling to the camera

How much protein?

Most of our diets lack the amount of protein required for maximizing muscle growth. Therefore, protein supplements come in handy as an easy and cheap solution.

I have already written an extensive article how to figure out how much protein you need per day. Accurately estimating that will put you in the safe zone. Zone where you are not losing muscle due to under-consuming protein and not causing damage to your organs due to over-consuming protein.

If you just want to eye-ball it, you might use a simple formula:

Weight (lbs) x 0.8 = Total Daily Protein Intake

How we build muscle:

When we weight train, we are creating micro-tears in our muscles. Building muscle is all about refilling these tears.

1. In order to rebuild these tears, muscle will require more protein intake then usually. Process when protein is produced to repair muscle damage is called Muscle Protein Sythesis (MPS)

2. If that is not delivered, weight training will be only degrade our muscles. Process in which protein is lost as a result of exercise is called Muscle Protein Breakdown (MPB).

Therefore, the only thing that really matter whether your muscle tissue is build or lost will be ratio between MPS and MPB.

1. Building muscle = MPS > MPB
2. Losing muscle = MPS < MPB

Therefore, our goal should be:
1. Low Muscle Protein Breakdown
2. High Muscle Protein Synthesis

Personal trainer in the gym. Thinking when he should have his protein drink



MPB is proven to be only slightly elevated straight after workout. That means that we do not have to prevent muscle break down at all.

But….Muscle Protein Breakdown is significaly raised post-workout when you are in a fasted state. That means that if you haven’t had any food 5 hours before the workout, your body is more likely to break down muscles.

Therefore, drinking a protein shake (+some carbohydrates) right after workout will only be important if you train on an empty stomach.


Muscle Protein Synthesis shows how sensitive your muscle is towards receiving amino-acids. The bigger the sensitivity the bigger the gains. Based on the research, initial spike in synthesis is released within 3 hours after the workout. What is more, MPS stays elevated for at least 48 hours after the workout. That goes to show that best time to drink protein shake would be from 3-48 hours after exercising.

Muscle Protein Synthesis graph shows biggest response 3 hours after the workout. Line stays elevated even after 48 hours.

Myth of Anabolic Window

Let’s go back to anabolic window discussion. Anabolic window is a phase within you should be drinking protein shakes. The rule states that the best time to drink a protein shake is within 30 minutes after your workout. After that, the window closes. If you missed it, your muscles will not grow.

Anabolic window is a myth because it assumes two things we debunked above:

1.MYTH: Muscle Protein Breakdown is significantly elevated after exercise

FACT: MPB is only significantly elevated when we train in the fasted state. If you had your breakfast before the workout, do not worry about that.

2. MYTH: Muscle Protein Synthesis is highest straight after exercises and it drops down after 30 minutes

FACT: MPS is highest at 3 hours after exercise and stays high for 48 hours after

Need more convincing?

1. Study The Effect of protein timing on muscle strength and hypertrophy initially showed small to moderate effect on influencing muscle growth. However, all these subjects were also on a higher total protein intake. Study suggested that timing barely plays any role. By far, the most important thing is Total Daily Protein Intake.

2.Study researched effect on. Pre VS post-exercise protein intake, and its effect on muscle growth. They have concluded that effects are same.

Therefore, it does NOT matter whether you drink a protein shake straight before or straight after the workout. That just goes to show what previous study already suggested: Only thing that matters is Total Daily Protein Intake!

Best time to drink protein? Man pushing the tire on the floor, working out


Well, assuming you not fasting, the answer is really simple.

“Best time to drink protein shakes is whatever fucking time you want to”



Firstly, protein shake is nothing else but additional source of protein that you did not get from eating real food. Drinking a protein shake or eating chicken breast have the same effect. Only difference is that consuming supplements is little more convenient and usually cheaper.

Only way to build muscle is to have bigger Muscle Protein Synthesis as opposed to Muscle Protein Breakdown. We found out that we need to do two things for that to happen:

1. Never train fasted (but if you are, make sure to drink protein shake straight after to avoid MPB)
2. Consume enough protein throughout the day

30-minutes Anabolic Window is bunch of horse-shit. Nothing magically happens in your body just because the timer is 30 minutes after you completed your last set of bicep curls.

Rather than worrying about that, you should concern more about eating clean foods and calculating your ideal protein intake.


About the Author

Hey, my name is Ire.I am a Personal Trainer/ Strength Coach based in Stockholm, Sweden.When you don't find me in the gym, I will most likely be on a Track and Field stadium throwing around a discus.