Are Post-Workout Protein Shakes Necessary?
Core - Edition Nº01
So, are protein shakes a waste of time?
If you have little interest in the in-depth answer to this question, then sorry; it’s a bit more complicated than yes or no. Whether or not you should be swigging your favourite post-workout protein shake immediately after a workout depends on a few caveats that vary from person to person.
Let me explain.
Why Is Protein Important?
Protein is one of our four macronutrients, the essential nutrients you must consume in large amounts to support your health, growth and reproduction.
The four are:
Protein stores itself is in different parts of your body — muscle, bone, hair, skin and all tissue. It powers and supports the wealth of chemical processes that transpire in your body to keep you healthy and running smoothly.
Proteins, in particular, are compounds made up of molecules we call amino acids. Think of them as the building blocks of protein. They:
Regulate our sleep cycle
Stimulate muscle protein synthesis (MPS)
Improve oxygen circulation
Regulate brain activity (e.g. alertness, depression, etc.)
Produce and store energy
While there are hundreds of different amino acids in the world, there are 22 which can make all the proteins needed in the body. Eight of them are recognised as “essential”, which means they have to come from your diet—because the body can’t make them—while the rest are “non-essential” as the body makes them by itself. They help your body grow and repair muscle tissue while protecting your lean body mass (muscle mass). And since intense exercise can cause microscopic tears or damage your muscles, protein intake becomes a question of “when”, not “if”.
So Protein Is Necessary, but Are Protein shakes?
Protein shakes come in countless forms, flavours, and styles. You can whip one up in seconds in the changing room of your local gym or buy one at your local café. They are reliable when you want to meet your daily protein needs, and they’re good at satisfying your hunger until you have your real post-workout meal.
Or maybe you enjoy drinking one for pleasure (probably not).
But are they necessary?
Dr Jamie Schehr says it’s a good idea to consume protein within the first hour of a workout, with 30-60 minutes being the sweet spot for men and women. In terms of amount, 10-20g for women and 30-40g for men is a good starting point.
My take is it depends on your situation like it depends if you had asked, “How often should I go to the gym?” Or “Which fitness plan is right for me?”
If you’ve been into fitness for a while, you’ve probably heard someone tell you about the need to have protein within 20-60 minutes of a workout.
And maybe you’ve then thought, what is this person talking about?
This “window” of opportunity is called the Anabolic Window, or the crucial timeframe to ingest protein to avoid serious muscle breakdown. Anabolism is when small molecules start to grow into bigger, complex molecules. And these form into new cells and tissues, which includes muscle.
After a hard workout, your tends body goes into an anabolic state. It calls upon glucose (sugar) to provide the energy needed to use your muscles and help you move. Your body also uses adenosine triphosphate (ATP), which provides power for up to three seconds and require oxygen to be created. Lactic acid forms instead when there isn’t enough oxygen (but remember: lactic acid doesn’t cause muscle soreness—that’s hydrogen buildup).
According to anabolic state theory, our anabolic response is limited to 30 minutes and refers to Muscle Protein Synthesis (building muscle) exceeding Muscle Protein Breakdown (losing muscle). However, there’s enough research to suggest this window doesn’t exist.
While I was at University, my course leader taught me that this “window” you often hear about is a myth; instead, you can go 1-3 hours without consuming protein and still experience similar effects. "High-quality and short-term muscle biopsy studies report similar muscle anabolism after consuming an essential amino acid mix one, two or even three hours post-exercise”, says Oliver Witard, a lecturer and researcher of protein metabolism at the University of Sterling in Scotland.
What was also confusing to me was that this “window” always differed from person to person. Some people I asked said it had to be within 20 minutes—others said one hour. That helped me understand that most people don’t know either.
I used to be an avid believer in having protein immediately after a workout in the beginning. But I never saw a noticeable difference whether I had a protein shake immediately or hours later.
What The Science Says
Post-workout nutrition should replenish critical areas of the body, such as our glycogen stores (glycogen is glucose in storage form, while glucose is blood sugar from carbohydrates). High-volume and high-intensity exercise tends to deplete these stores, which is what makes us tired.
Studies suggest that delaying carbohydrate consumption by two hours can reduce the rate at which our muscle glycogen stores are replenished by up to 50 percent. In other words, your body can struggle to renew your energy levels and power your muscles as they try to recover.
There’s been a long battle between studies about this concept. Some found that consuming protein-carbohydrate supplements after the 2-hour mark does improve glycogen resynthesis, while other studies couldn’t support these findings as they found no significant difference.
One study found that unless we’re doing two-a-day split sessions, the urgency to top up our energy stores is far less than we think. This matches what I found at University as track cyclists often ingested a post-workout shake immediately after the finish line because they were competing again later that day or from the morning after. Watch any finish of a bike race, and you’ll see athletes get given water and a protein shake quickly after they stop and settle down.
Muscle Protein Breakdown (MBP)
The big argument supporting post-workout shakes was that they’re crucial in preventing MBP. But studies found that consuming carbohydrates is equally vital as protein consumption.
Some research found that the breakdown process slightly escalates after exercise and promptly increases as time goes on. However, Muscle Protein Synthesis (MPS) also increases post-exercise. MPB is inhibited through insulin and glycogen. So, even in a fasted state, MPB only raises significantly after the 3-hour mark. But at 60 minutes, there’s no breakdown process.
Muscle Protein Synthesis (MPS)
Muscle Protein Synthesis is what most people hold as their rationale for downing their protein shakes as early and fast as possible. However, studies suggest the benefits of this are limited. And more studies found no significant difference between consuming post-workout nutrition one hour after exercise and three hours after.
You’re still here?! Fantastic.
Ultimately, protein shakes can be necessary after a workout. But it depends on:
Whether you’re doing multiple activities in one day
Whether you train late and go again the following day
Whether you know that you’re not going to get enough protein in the day
Whether on a busy schedule
From all the research, I don’t believe the 30-minute window exists. A later post-workout meal won’t significantly hinder muscle growth, nor will consuming protein five seconds after your last rep help your gains. So, take your time, enjoy your shake, and eat as best you can!