Across strength sports, athletes have all different approaches to nutrition. But one common unifier? Protein — and a lot of it. No matter your goals on the lifting platform, you probably have a love affair with protein. It’s essential for building muscle, maintaining lean muscle during fat loss, and recovery from exercise.
But sometimes, even the most dedicated lifter gets tired of trying to eat enough tofu or chicken to hit their protein intake goal. Instead, you’ll reach for protein powder to make a quick shake — and for good reason. Ingesting protein post-workout is one way to be sure your muscles have enough amino acids to repair themselves and grow after breaking them down in the gym.
But is post-workout the only time that works? When is the best time to drink a protein shake? Let’s dive into the research behind nutrient timing, how protein can benefit your fitness goals, the types to choose from, and how much you should be getting.
Editor’s Note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. When starting a new training regimen and/or diet, it is always a good idea to consult with a trusted medical professional. We are not a medical resource. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. They are not substitutes for consulting a qualified medical professional.
- When is the Best Time to Consume Protein?
- How Protein Helps Your Fitness
- Different Types of Protein
- How Much Protein Do You Need Per Day?
- Frequently Asked Questions
Protein is made up of amino acids, which are the building blocks of muscle in your body. Your body needs enough amino acids to undergo muscle protein synthesis — or muscle growth — when paired with resistance training. If you’re grabbing a protein shake to help hit your goals, the time of day you drink it may not matter as much as your overall intake.
The International Society of Sports Nutrition (ISSN) states that the best time to ingest protein is up to each individual and what they can tolerate. However, there are potential benefits to pre- and post-workout protein consumption and the anabolic effect may last throughout the day. (1)
The anabolic effect refers to the stimulation of muscle protein synthesis. Research has examined whether or not ingesting protein immediately after training — or your “anabolic window” — is most optimal because your muscles may be more primed to absorb amino acids to repair themselves and grow. (1) Let’s break it down further.
Throughout the Day
You can drink a protein shake at any point during the day. The ISSN suggests that meeting your daily protein intake through your meals, snacks, or shakes — spaced out throughout the day — should be your main focus if you are exercising. (2)
While a protein shake can be a great addition to help you reach your target, prioritize getting enough protein during the rest of the day through whole food sources. Your body needs enough to undergo muscle protein synthesis throughout the day and not just around your workouts.
When it comes to macros, carbohydrates provide your body with energy for your workout. Some people opt for taking a pre-workout supplement for extra energy and focus. There’s some evidence that consuming protein — with carbs — before your workout can also help with muscle protein synthesis. (1)
One study was done on a group of 21 men with resistance training experience. For ten weeks, combined with a resistance training program, half the group ingested 25 grams of protein and one gram of carbohydrates pre-workout and the other half consumed the same supplement post-workout. Both groups had similar results when it came to hypertrophy, strength, and body composition. The study suggests there was no difference in timing their protein intake before or after training. (3)
Eating a heavy meal with protein before training may make you feel sluggish during your workout. A fast-digesting protein supplement that is quickly absorbed like whey protein or soy protein may feel better if you’re opting for a pre-workout shake.
After training, your body needs carbohydrates to replenish your glycogen stores, and protein to start repairing your muscle tissue. Getting 20 to 40 grams of a high-quality, complete protein source immediately to two hours after your session has been repeatedly shown to help stimulate muscle protein synthesis. (2)
High-quality protein means that it is quickly absorbed. Complete protein refers to protein sources that contain all of your essential amino acids including your muscle-building branched-chain amino acids (BCAAs). Leucine in particular is a precursor for muscle protein synthesis and can be a helpful addition to your post-workout shake. (4)
Around the platform, you may have heard that you need to take in protein within 30 minutes of completing your workout — or risk not making gains. (5) That’s no longer believed to be true — the anabolic window may last up to 24 hours after your session. However, the ISSN notes that benefits may diminish as you get further away from the end of your workout. (2)
No need to panic if you can’t get your shake within 30 minutes — consuming it within a few hours can still stimulate your gains.
Sleep is a key part of exercise recovery. Muscle protein synthesis occurs as you rest and recover. Sure enough, studies suggest that ingesting protein before bed can increase it.
Consuming protein immediately before going to sleep increases the availability of amino acids overnight. With more amino acids available while you’re in bed, muscle protein synthesis will be stimulated so your muscles can grow overnight as you recover. (6)
It should be noted that ingesting protein before bed can help with muscle growth only when combined with following a resistance training program. Drinking a protein shake without lifting weights won’t make you magically build muscle mass overnight. (6)
One study that first showed this was on casein protein. Subjects ingested 40 grams of casein protein before bed, and it was digested and absorbed well enough to increase muscle protein synthesis. Casein is slow-digesting, which may explain why it was able to work longer during the time the subjects were asleep. (7)
Protein plays a key role in all fitness goals. Whether you are trying to build muscle mass, lose body fat, boost your athletic performance, or optimize your recovery — you need protein.
How Protein Helps Muscle Growth
Protein — when paired with a resistance training program — has been widely studied and is well known to help build skeletal muscle by repairing muscle tissue during recovery from exercise. (8)
If your goal is hypertrophy, or muscle gain, you’re likely engaging in weight lifting in a resistance training program. When you train, you break down your muscle fibers. When you consume protein, you repair them so they can regenerate and grow.
Muscle protein consists of 20 amino acids, including nine essential amino acids and 11 non-essential amino acids. Essential amino acids cannot be produced in your body and must be ingested through your diet. (9) Your body needs all 20 amino acids for hypertrophy to occur. (10)
Complete protein sources contain all your amino acids. To build muscle, in addition to training and eating enough calories, you’ll need to consume enough complete protein to see your hard work in the gym pay off.
How Protein Helps Fat Loss
If you’re following a training and nutrition plan for weight loss, you’re likely reducing your intake through fewer calories or smaller portions. Protein is known to increase satiety more than the other macronutrients — consuming enough protein can help you feel and stay fuller longer between meals. Aiming for a high-protein diet when trying to lose fat may help you stick to your program.
You can lose weight by consuming fewer calories than your body needs. Hitting your protein intake goals can ensure that your body preserves its lean muscle mass while you lose body fat. (11)
Protein may also have a higher thermogenic effect on your body when you eat it, meaning it requires more energy to digest. (11) This can minimally boost your total daily energy expenditure (TDEE), so eating protein may help you burn a few more calories.
How Protein Helps Athletic Performance
Protein may not seem to have a direct impact on your athletic performance on an average day at the gym. It’s not a source of energy like carbs or pre-workout. However, consistently hitting your protein goals over time can help you to recover better, build muscle, and show up to your workouts ready to perform your best. This may lead to strength gains over time.
Endurance athletes are advised to focus on their carbohydrate intake before and after training to maximize and replenish their glycogen stores. (1) When refueling with carbs after an endurance session, including post-workout protein is optimal to reduce muscle damage. (2)
How Protein Helps Recovery
Certain types of protein (like whey) have anti-inflammatory and antioxidant properties. (13) Some inflammation after exercise or oxidative stress isn’t necessarily a bad thing — it’s needed for growth. Inflammation can lead to pain, reduced muscle function, and soreness. (14)
Recovering better from these symptoms by getting quality protein can help you get back in the gym quicker, stronger, and ready to crush your workouts.
You can get protein through food sources and different types of protein powder. It’s recommended by nutritionists and health professionals to try and get most of your protein through natural whole food sources if possible and opt for protein supplements as additions to your diet.
Protein occurs naturally in animal-based and plant-based foods.
High-Protein Animal-Based Foods
If you eat meat and/or dairy, here are some options for you:
High-Protein Plant-Based Foods
For the vegans and vegetarians out there, try these out.
If you want to add a natural source of protein to your protein shake, Greek yogurt is a high-protein option. You can also get a dairy-free version of this to support a vegan diet.
Whey Protein Powder
Whey protein is a dairy-based protein powder derived from cow’s milk. It is both a high-quality and complete protein source — it contains all of the essential amino acids needed to build muscle. The amino acids are readily bioavailable, meaning they can be quickly absorbed after rapid digestion. (15)
Whey protein comes in three types: whey concentrate, whey isolate, and whey hydrolysate.
Due to its high quality and well-researched muscle-building properties, whey protein may be the best animal-based protein powder you can get. However, it’s not an option on a vegan diet. It’s also lactose-based, so if you are lactose intolerant it may not work for you.
Casein Protein Powder
Casein protein is also derived from cow’s milk. Unlike whey, it digests slowly and releases amino acids over time. Because of its slow and sustained release from amino acids, this might be your best protein option before bed. (7)
Soy Protein Powder
Soy protein is a vegan, plant-based protein powder. It contains all of your essential amino acids needed to build muscle, making it a complete and high-quality protein source that offers similar benefits to whey protein. Soy protein powder may be the best protein choice for vegan athletes looking to boost their protein intake.
Plant-Based Protein Powder
The Food and Drug Administration (FDA) recommends 50 grams of protein per day — but that’s the minimum amount required for your body to function. (15) But everyone has different body types, goals, and activity levels. So what is the truth?
Check out BarBend’s protein intake calculator to get your tailored needs.
Protein Intake Calculator
The American College of Sports Medicine (ACSM) recommends 1.2 to 1.7 grams of protein per kilogram of body weight for active people. This comes out to 0.5 to 0.8 grams of protein per pound of body weight. (16) What does “active” mean to you? The numbers may change a little if you are trying to gain muscle or lose body fat.
For Muscle Growth
There have been many studies trying to nail down the perfect number for muscle growth. If you’re trying to gain muscle mass, be sure you are training appropriately and getting enough calories to be in a surplus.
The American College of Sports Medicine (ACSM) says that 1.6 grams per kilogram of body weight should be the minimum intake for muscle gain, and over 2.2 grams may be unnecessary. (16) The ISSN says 1.4 to 2.0 grams of protein per kilogram of body weight is sufficient for gaining and maintaining muscle mass. (1)
If you’re a serious, competitive bodybuilder, some research shows you may need more than these suggested ranges. Evidence shows that most, but not all, bodybuilders may hit their goals by aiming for 2.3 to 3.1 grams of protein per kilogram of body weight per day. (17)
If you’re trying to gain muscle but not competing, aiming to stay in the 1.4 to 2.2 grams per kilogram of body weight range should be sufficient for you. Again, your individual needs may vary.
For Fat Loss
When you’re trying to lose body fat, some evidence shows you may need a little more protein than the standard one gram per kilogram. If you’re restricting calories and resistance training, the ISSN suggests 2.3 to 3.1 grams per kilogram of body weight to retain your lean muscle. (1)
A study was done on young men doing a high volume of resistance training, six days a week for four weeks. They all were in a high calorie deficit (40 percent). Half the group consumed lower protein (1.2 grams per kilogram) and the other half consumed higher protein (2.4 grams per kilogram).
The higher protein group retained more lean muscle mass and lost more body fat than the lower protein group. (18)
Shake It Up Any Time
Protein is important to your overall health and fitness goals, especially when it comes to body composition. If you’re resistance training and trying to gain muscle or lose body fat, it’s important to keep your intake high enough to help your body recover.
Protein shakes are a great option to help you reach your goals, but it’s always advisable to get as much as you can through whole food sources first. There is nothing magical about a protein shake — it’s simply an efficient way to boost your intake, and the timing of it may not matter as much as it was originally claimed.
Pre-workout, post-workout, or before bed, it’s most important to reach your overall intake goals throughout the day. But all that protein powder is still a quick way to refuel your muscles after your workout — so if you enjoy a nice shake after training hard, shake it up and enjoy.
Have some lingering questions about protein shakes? Let’s get some answers.
Is it better to drink a protein shake in the morning or at night?
It all depends on your preference and goals.
Drinking a protein shake in the morning can help to replenish your amino acids after sleeping. Starting the day feeling full can also set you up to stick to your plan if you’re trying to reduce your food intake for fat loss.
Drinking a protein shake at night has been shown to boost muscle protein synthesis during overnight recovery. If your main goal is building muscle, night wins out over morning.
Is it OK to drink a protein shake on an empty stomach?
Most types of protein powder are easily digested. However, each individual is different. It is generally safe to drink a protein shake on an empty stomach, but if you have a sensitive stomach, you may experience discomfort or bloating.
How often should you drink protein shakes?
You can drink a protein shake every day if it supports your goals. However, you should aim to get most of your protein and nutrients through whole food sources first.
How soon after working out should you drink a protein shake?
You can drink your protein shake right after working out. It was previously thought that you had to consume it within 30 minutes of training, but your “anabolic window” may be longer than that.
Drinking your protein shake at any point during the day will contribute to your overall intake and get you towards your goals.
How many grams of protein should you have in your shake?
You want to be sure you’re getting enough leucine in your shake to stimulate muscle protein synthesis. Protein powder often contains 20 to 30 grams of protein per serving, and you can usually get enough leucine in that amount of high-quality protein. (19)
Remember to think of the amount of protein in your protein shake as part of the larger picture of your daily protein intake. Your individual needs may vary.
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