Protein is arguably the most important nutrient for people who exercise. This will double if you are training for strength or muscle growth. Intense training causes muscle catabolism or breakdown.
Your body needs protein and the amino acids it contains to repair this damage and make your muscles bigger and stronger. Too little protein could hamper your progress.
How much protein you actually need is up for debate. The RDA (recommended daily amount) for protein is a meager 0.36 grams per pound of body weight (1). That’s enough to support a sedentary person, but probably not enough for a dedicated athlete.
In contrast, studies suggest that people who train hard and often need more than double the RDI for protein to get the most from their workouts. This means at least 0.72 grams per pound of body weight (2).
Many bodybuilders err on the side of caution and consume one gram per pound. This nice round number makes it easier to calculate your macros. It also ensures that there is protein to spare, thus eliminating the danger of a deficiency.
Use our protein calculator to estimate your recommended daily intake.
While it is possible to get enough protein from food, it is not always practical. After all, you can ruffle your boss or teacher’s feathers if you keep eating chicken thighs and tuna every few hours.
This is where protein powders come in.
Protein powder makes getting enough of this essential macronutrient much easier. Just mix a spoon or two with the water and drink it. Most protein powders provide 20 to 25 grams of protein per serving, making it much easier to meet your daily protein intake goal.
But should you consume your protein shake before or after training? Let’s talk!
Protein before training
Some athletes like to consume a protein shake before training. The idea is that the shake will help prevent muscle catabolism. And, at the end of the workout, the amino acids in the shake will be available to jumpstart the processes of muscle repair and growth.
While this concept makes sense on paper, there is no evidence to support it (3). It can even interfere with your workout.
Exercise diverts blood from the digestive system to provide more oxygen to trained muscles. This brings the digestive process to an almost complete stop. Protein eaten immediately before exercise will mostly stay in the stomach, where it will not be digested. It will definitely not be available for your muscles to use.
Consuming protein before exercise can also cause an insulin spike and a corresponding drop in blood sugar. This could tire you out and even affect the duration and intensity of the workout.
Depending on your tolerance for the food in your stomach during exercise, this could cause abdominal bloating and upset stomach. Most people find exercise more comfortable if their stomachs are empty.
Related: How Long Should You Wait To Work Out After Eating?
Pre-workout supplements provide energy without bulk and are designed to work really fast. This is why they are generally well tolerated before exercise. However, they are more fluid than food, which is why they are digested so quickly. Even in the form of a shake, protein is more of a food than a liquid, so it takes longer to digest.
Summary – Consuming a protein shake before training does not bring any real benefit and could hinder your training by causing an upset stomach or lowering blood sugar.
Protein after training
While some athletes like to drink a protein shake before training, most tend to consume protein powder after exercise. In fact, because of what is called “the anabolic window”, many athletes will do their best to drink a protein shake within 30 minutes of finishing their workout.
For the most part, the protein of choice is whey protein. This is because it is digested quickly and increases protein metabolism after exercise more than casein and other types of protein powder (4Trusted).
However, research suggests that the anabolic window is much longer than the 30 minutes most people believe. In fact, it could take several hours (5). This means that there is really no rush to drink a protein shake immediately after training. Instead, you can grab a protein shake or eat a protein-rich meal within hours of your workout.
Learn more about the latest research on the anabolic window here.
While your body needs protein after training, how quickly you consume it and what form it takes doesn’t seem to matter. While drinking a protein shake immediately after your workout is convenient, there is no reason not to continue doing so. But if you’d rather wait a bit or eat a protein-rich meal instead, that will work, too.
Summary – the anabolic window lasts much longer than initially thought. Three hours or more, and not just 30 minutes. While consuming a fast-acting whey protein shake or similar immediately after exercise won’t harm your gains, it’s not essential.
Daily protein intake is more important than timing of nutrients
Studies indicate that getting enough protein each day is much more important than when you are consuming your protein shakes (7). Using protein powder immediately before and after exercise appears to have the same effects and benefits.
So, don’t worry too much about whether it’s best to consume protein before or after exercise. Instead, focus on what’s practical.
If you prefer to consume your protein shake before training and it does not cause any side effects, you should continue to do so. Or, if you like a protein shake right after the last set of your workout, there’s no reason to stop.
Ultimately, both options can work and you can choose to do one, both, or neither. What’s MORE important is meeting your daily protein intake goal. A protein deficiency will jeopardize your progress much more than the timing of your protein shake.
For most of us, getting enough protein means consuming high protein foods at all main meals (breakfast, lunch, and dinner) and then consuming high protein snacks between meals.
Good options include foil packets of tuna and salmon, jerky beef and turkey, hard-boiled eggs, nuts and seeds, and basic protein shakes for bodybuilding.
So don’t worry if you finish your workout and realize you forgot your shaker or protein powder. Just eat a protein rich meal or shake when it’s convenient for you. Before bed, make sure you’ve reached your protein intake goal for the day.
As bodybuilders much of what we do and believe is based on “brother science”. These are the ideas and beliefs associated with training and nutrition that are not always supported by research.
In some cases, bro-science stands up to scientific scrutiny, and what we believe to be true ultimately turns out to be exactly that. In other cases, “real” science exposes bro-science to be incorrect.
Turns out the anabolic window is the best of bro-science. It makes a lot of sense on paper, but in reality it doesn’t exist as we think it is. In fact, rather than being a narrow period of just 30 minutes, the anabolic window is more like a double-wide garage, lasting several hours.
The timing of the protein shake is another example of well-meaning but scientifically contested bro-science. It doesn’t matter if you consume protein shakes before or after training. Instead, just make sure you’re getting enough protein each day. Not getting enough protein will compromise your progress much more than choosing between pre or post workout protein shakes.
1 – Harvard Medical School: How much protein do you need each day? https://www.health.harvard.edu/blog/how-much-protein-do-you-need-every-day-201506188096
2 – British Journal of Sports Medicine: A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults https://bjsm.bmj.com/content/52/6/376
3 – PubMed: Protein intake before and after exercise has similar effects on muscle adaptations https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5214805/
4 – PubMed: Whey Protein Supplementation Improves Whole Body Protein Metabolism and Performance Recovery After Resistance Exercise: A Double-Blind Crossover Study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537849/
5 – PubMed: Nutrient timing revisited: is there a post-exercise anabolic window? https://pubmed.ncbi.nlm.nih.gov/23360586/
6 – PubMed: The effect of protein synchronization on muscle strength and hypertrophy: a meta-analysis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3879660/
7 – PubMed: Recent insights into the role of dietary protein in promoting muscle hypertrophy with resistance exercise training https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5852756/