I think you’ll agree with me when I say…
With all the evolving science and research, it’s hard to know when and how often you should have a protein shake. One day, an Instagram fitness influencer tells you to drink one after a workout, and the next day, your fit friend says it doesn’t matter anymore.
Should you take protein shakes on rest days? Should you have them after a workout? What about before the workout? So many questions that need answering!
Well, it’s your lucky day. We’ve done the research to find the answers, so you don’t have to. We’ll tell you whether or not to drink protein shakes on rest days. And we’ll break down the ever-evolving science to see what’s most accurate for today.
In this post, we’ll go through the benefits of protein shakes on overall health, some recent scientific updates, and specific recommendations based on different fitness goals for men and women. Let’s get into it!
Table of Contents
Are There Benefits When I Drink Protein Shakes?
Let’s start with some background information to make sure we’re all on the same page. Do protein supplements have benefits?
An analysis of 49 studies using 1,800+ people showed that consuming extra protein helped increase strength and muscle size for those who were resistance training. They concluded that eating more than 1.6 grams of protein per kilogram (0.7 grams per pound) of body weight per day did not have additional benefits.
So, according to this study, if you are under-eating protein in your regular diet, supplementing with up to 1.6 grams of protein per kilogram would help. Having a protein shake is a convenient way to get the amount of protein you need — and it takes only minutes to prepare. Generally speaking, drinking a protein shake should benefit you. Easy peasy.
So how much is 1.6 grams per kilogram per day?
We made this handy-dandy protein calculator to make it easy to figure out how many grams of protein you need per day.
Just plug in your the type of training you will be doing, your weight, and the number of meals and snacks you have each day.
Protein Requirements Calculator
So, you know how much protein you require daily, but what does that look like on your plate? What portion of your meals should be protein? And what about fats and carbohydrates? These three nutritional components are macronutrients, essential for a healthy diet.
According to the Health and Medicine Division of the National Academies of Sciences, Engineering, and Medicine, the recommended intakes of macronutrients are as follows.
- Protein: 10–35% of energy intake
- Fat: 20–35% of energy intake
- Carbohydrate: 45–65% of energy intake
Your specific macronutrient percentages will depend on your body composition and fitness goals (which we’ll discuss below).
What the Research Says About Timing Protein Intake for Muscle Growth
Now that we’ve confirmed there are benefits to consuming protein, let’s look at some new science related to the timing of protein consumption. Conventional wisdom has held that having a post-workout shake will improve your returns in the gym. Let’s break this down.
Working out is incredibly stressful for the body. During a workout, cortisol builds up in the body, and muscle fibres start breaking down. This is a normal process, but it’s believed that you can shut down this muscle breakdown process by consuming protein. And by doing this, you can maintain and build more muscle mass.
If conventional wisdom holds true, the end result of a post-workout shake should increase muscle protein synthesis and decrease muscle breakdown from your workout. So, post-workout shakes are good, right? Hold on, not so fast.
An older 2013 analysis of 20 studies and 478 participants shows only minor improvements in muscle mass when looking at how protein timing affects both muscle mass and strength. However, as the analysis dives deeper, it shows the muscle mass gained is not statistically significant. It goes on to say that the total amount of protein consumed, rather than the timing, has a much stronger effect on muscle mass and strength.
So, now we have some conflicting evidence for having a post-workout shake. Darn.
As a strength coach, I prefer to play it safe and mention the timing aspect to clients. Having a post-workout shake may help in the long run by contributing to small potential gains. However, I will also tell clients that it’s much more important to focus on getting the full amount of protein per day instead of getting one protein shake timed perfectly.
Again, I’ll repeat — you should focus on consuming enough protein. Use the calculator above, and start recording what you eat to determine your protein intake.
With all this in mind, let’s answer the question you came here for: Should you take protein shakes on rest days? Let’s look at a few different fitness goals so you can find the answer that suits you best.
What Are Your Fitness Goals?
So, we’ve covered why having a protein shake is worthwhile, but let’s narrow in and look at individual scenarios. This way, you can figure out if it’s beneficial to have a protein shake if your goals are to lose weight, stay active, or work on building muscle.
Scenario 1: Weight Loss Goal
Does supplementing with protein help in this scenario? Weight loss is one of the most common motivators in the fitness industry, so it makes sense to address this first.
Let’s look at a study on obesity in which 158 participants aged 25–50 were asked to reduce their dietary intake by 500 calories per day. The participants were split into two groups: one group consumed a whey protein shake (leucine, peptides, and milk calcium), and a control group did not. At the end of 12 weeks, the supplementation group had a higher percentage of of protein in their diet. Very obvious, I know.
Of interest is that both groups lost a significant amount of weight due to the calorie-reduced diet…again pretty obvious stuff. However, the group supplementing with protein powder lost significantly more body fat and maintained more lean muscle.
So, if you’re trying to lose weight, it might be worth consuming a protein drink on rest days. Again, this ties into how much protein you eat every day with the rest of your meals, so figure out what you’re already consuming and supplement as needed.
How do you find out how much protein you’re consuming, you ask? Here are two convenient ways.
- Use a simple protein chart and a food journal like the ones provided below.
This chart gives you a quick visual to get an idea of the protein content in some basic foods (that you should probably add to your diet ☺️).
This food journal is super simple — print it out and try it! Fill it out for one day to see how much protein you consume. After you’ve recorded your food for the day, use Google to research the protein content of each food. Calculate the total, and presto: you know how much protein you ate in a day.
Compare this with your protein requirements calculations from above and adjust your daily diet accordingly.
- Use a food calculator app like MyFitnessPal to help determine what you eat throughout the day. Luckily for you, you can connect your MyFitnessPal account to our EverFlex app, so we can work on your food and fitness goals together!
Scenario 2: Maintain Weight, Active Individual, or Athlete
Are you an active individual or athlete who wants to maximize performance and lean body mass? For this scenario, there’s some evidence that having a protein shake on rest days could be beneficial. It depends on whether you’re hitting your recommended daily allowances or not for your protein needs.
Some recommendations have athletes and active individuals eating more than 1.6 grams per kilogram. A 2016 study on protein consumption mentioned that the American College of Sports Medicine suggests intakes of 1.2–2.0 grams of protein per kilogram of body weight per day. The lowers intake of ~1.2 grams is fine for those doing aerobic work and the higher dose of 2.0 grams is recommended for resistance training athletes.
Scenario 3: Bodybuilding or Aesthetics
We wish we could all be this intense during a workout, right? 🙃
A bodybuilder who’s bulking will typically aim for 25–30% of their caloric intake from protein. They’re trying to maximize the amount of available protein in the system during all of their extremely rigorous resistance training sessions.
If you’re resistance training often — and hard — and you’re looking to maximize the amount of lean body mass you can develop, you can start considering these larger percentages of protein intake. Some evidence suggests that high amounts of protein (30% versus 15% of energy intake) can help during energy restriction phases in bodybuilding.
This 30% recommendation equates to a high-protein diet and is much higher than for active individuals and athletes. It hits close to 2.2–2.6 grams of protein per kilogram of body weight per day. But wait — didn’t one of the studies above say anything above 1.6 grams doesn’t help? Correct.
There will always be conflicting evidence as evolving science is a bit of a minefield of information. Many bodybuilders still consume these large amounts of protein, hoping to prevent any lean mass loss and instead gain more lean muscle mass. The bodybuilding study listed above was written in 2004, so take it for what it’s worth.
For the average person weight training a few days a week, the active individual scenario (1.2–2.0 grams of protein per kilogram of body weight per day) should be fine. However, if you’re serious about living a bodybuilding lifestyle, you can start to incorporate higher protein amounts by adding shakes on non-workout days (which you won’t have many of anyway, due to the intense training schedule).
There are no guarantees that you will get extra results from this amount of protein, but it may be worth testing it out for a while to see if you discover any personal benefits.
Should You Take Protein Shakes on Rest Days?
OK — we aren’t all superstar athletes like the person above who probably needs a higher protein intake like the rest of us. Figuring out whether you should drink protein shakes on recovery days depends on your activity level, how much protein you already consume, and your required protein intake. Ask yourself these questions:
- Are you and will you continue to be sedentary?
- Shoot for 0.8 grams of protein per kilogram of body weight per day. If you’re not getting that amount from your diet, consider adding a protein supplement on rest days.
- Are you active and doing aerobic training mostly?
- Shoot for the lower end of the recommended 1.2–1.6 grams of protein per kilogram of body weight per day. You could use protein shakes on recovery days to reach your daily recommendation.
- Are you active and doing resistance training mostly?
- Check what you’re consuming, then factor in any heavy resistance training. Potentially use protein shakes on top of your regular intake to reach up to 2.0 grams of protein per kilogram of body weight per day.
- Are you completely focused on body building and training your physique?
- Calculate how much protein you’re ingesting. Play around with your intake amounts all the way up to 2.2-2.6 grams of protein per kilogram. Track everything rigorously to see if there are any benefits you are noticing.
If you have any questions at all reach out to a trainer or fitness professional who can go over this in more detail!
Let’s revisit the questions we asked at the top: Should you take protein shakes on rest days? Should you have them after a workout? What about before a workout?
Based on the science we consolidated, you should probably drink protein shakes on recovery days if you want optimal performance in the gym or on the field. The more you can get protein in your system, the better your chance for muscle growth.
For those seeking to lose weight, having adequate protein can be beneficial for losing body fat and maintaining muscle mass. Similarly, there are positive effects on lean body mass from an athletic standpoint. Anecdotally, bodybuilders have been consuming large amounts of protein for years and have impressive physiques (for multiple reasons).
Timing your protein shake before or after your workout may have a small effect, but that’s not where you should focus your effort. Instead, you should focus firmly on getting adequate protein per day and per meal.
Use our protein requirements calculator above to see your personalized recommendations for what you need to eat daily and per meal. From there, you can use our protein chart and food journal to find out if you’re eating the right amount of protein.
Finally, if you aren’t getting enough protein based on your goals and daily requirements, start adding a protein shake to increase your intake. It’s the easiest and quickest way to make an impact without changing your diet drastically.
Your body needs easy access to proteins, and one of the best ways of ensuring this is by drinking a protein shake, whether it’s a training day or a rest day. Or if you’re looking for the expertise of one of our nutrition coaches, get in touch with us today!