The 6 Best Supplements for Muscle Growth (2026): Fitness Expert Approved

For busy professionals balancing long workdays and limited downtime, muscle growth supplements can be a way to enhance your results. We’ve tested and selected the best supplements for muscle growth of the year. Read on for our picks of the best protein powder, post-workout, and more.

Best Supplements of Muscle Growth of 2026

• Best Supplement for Muscle Growth Overall: Transparent Labs 100% Grass-Fed Whey Protein Isolate
• Best Post-Workout Supplement for Muscle Growth: Swolverine Creatine
• Best Greens Powder for Muscle Growth: AG1 Next Gen
• Best Amino Acid Supplement for Muscle Growth: Transparent Labs BCAA
• Best Multivitamin Supplement for Muscle Growth: Legion Multivitamin
• Best Mass Gainer Supplement for Muscle Growth: Nutricost Mass Gainer

Best Supplements for Muscle Growth Comparison Table

Supplements for Muscle Growth	Main Ingredients	Form	Third-Party Testing	Serving Size
Transparent Labs 100% Grass-Fed Whey Protein Isolate	Whey from grass-fed cattle	Powder	Yes	28 grams of protein
Swolverine Creatine	Creatine monohydrate	Powder	Yes	5 grams of creatine
AG1 Next Gen	70+ vitamins, minerals, probiotics, and plant compounds	Greens powder	Yes	1 scoop
Transparent Labs BCAA	BCAA, l-glutamine, coconut water powder, vitamin C	Powder	Yes	1 scoop
Legion Multivitamin	Vitamin A, vitamin C, vitamin D3, vitamin E, vitamin B complex, ashwagandha root extract	Capsules	Yes	8 capsules
Nutricost Mass Gainer	Whey protein concentrate, creatine monohydrate, and l-glutamine	Powder	Yes	3 scoops

Transparent Labs 100% Grass-Fed Whey Protein Isolate
Main Ingredients	Whey from grass-fed cattle
Form	Powder
Third-Party Testing	Yes
Serving Size	28 grams of protein
Swolverine Creatine
Main Ingredients	Creatine monohydrate
Form	Powder
Third-Party Testing	Yes
Serving Size	5 grams of creatine
AG1 Next Gen
Main Ingredients	70+ vitamins, minerals, probiotics, and plant compounds
Form	Greens powder
Third-Party Testing	Yes
Serving Size	1 scoop
Transparent Labs BCAA
Main Ingredients	BCAA, l-glutamine, coconut water powder, vitamin C
Form	Powder
Third-Party Testing	Yes
Serving Size	1 scoop
Legion Multivitamin
Main Ingredients	Vitamin A, vitamin C, vitamin D3, vitamin E, vitamin B complex, ashwagandha root extract
Form	Capsules
Third-Party Testing	Yes
Serving Size	8 capsules
Nutricost Mass Gainer
Main Ingredients	Whey protein concentrate, creatine monohydrate, and l-glutamine
Form	Powder
Third-Party Testing	Yes
Serving Size	3 scoops

Best Supplement for Muscle Growth Overall: Transparent Labs 100% Grass-Fed Whey Isolate

Our Thoughts on Transparent Labs 100% Grass-Fed Whey Isolate

Transparent Labs 100% Grass-Fed Whey Isolate is our pick for the best supplement for muscle growth overall, because it contains 28 grams of protein per serving, sourced from grass-fed cattle. The brand is third-party tested and incredibly transparent, posting their COAs on page. This product is also Informed Choice and Informed Sport certified, so athletes and gym-goers alike can build muscle while trusting the purity and safety of this protein powder. It tastes good, too.

Kayla tested our best protein supplement for muscle growth, rating her first impression of the product a 5 out of 5. “Transparent Labs has a reputable reputation in the supplement industry, so my first impression is on par with the exceptional brand that they are,” she said. The packaging is simple and clean, and provided all the information that Kayla wanted to know without being overwhelming. 

The instructions were clear, and mixability scored a 5 out of 5. “After shaking the bottle of powder and water together for 60 seconds, it came out super smooth and not grainy,” Kayla noted. “The mix has a small layer of foam at the top, but it’s not super thick. I used 8 ounces of water, which seems to be a good consistency–anything over 10 ounces would make it too watery.”

Kayla loved the taste, rating this protein powder a 5 out of 5. She considered the sweetness to be middle of the road, rating it a 3 out of 5. “Taste is my number one consideration along with the percent of protein to calories when choosing a protein powder,” she said. “With this product having 28 grams of protein and only 130 calories, I wondered if it would lack taste—but I was left with zero disappointment,” Kayla mused. “There is a slight sweetness to it that is not overwhelming, and a frothy, slightly fuller body texture to it, more like a milky consistency.”

“While this is a pricier protein, you are paying for the quality and transparency. I’ll gladly pay the price to know that I’m getting a ton of protein compared to calories. It tastes good, and I don’t have to worry about where the ingredients are coming from,” Kayla said.

Check out our list of the best protein powders of the year.

Best Post-Workout Supplement for Muscle Growth: Swolverine Creatine

Our Thoughts on Swolverine Creatine

Swolverine Creatine is our pick for the best post-workout supplement for muscle growth. While research remains mixed on timing for creatine (pre-workout or post-workout), we like the idea of taking creatine after a workout, when your muscles are primed to receive nutrients. If you take creatine post-workout with a meal or a shake, it also raises your insulin, which supports the transport of creatine to your muscles.

Pete, a certified nutrition coach, tested Swolverine’s creatine. He rated his first impression of the product a 5 out of 5. “It’s a small plastic container with a screw-top lid. The label is white with black and blue lettering that’s easy to read,” he said. “This is probably small enough for most people to consider it travel-friendly.”

The directions are also straightforward: “Add one scoop of micronized creatine monohydrate with 10 ounces of water or beverage of your choice on training and non-training days.” Pete rated them a 5 out of 5—easy to understand and follow.

The creatine dissolved well when Pete mixed it. “It fully dissolved in 60 seconds, and it has a smooth consistency with no chunks or clumping,” he said, rating mixability a 5 out of 5. It wasn’t sweet at all, as it’s unflavored, and Pete rated the sweetness the lowest level possible, at a 1. It’s truly unflavored, and we think it would stack well with another flavored supplement or electrolytes.

Pete didn’t experience any side effects or digestive upset after testing this creatine, rating it a 5 out of 5 for side effects.

Check out our full list of the best creatine supplements.

Best Greens Powder for Muscle Growth: AG1 Next Gen

Our Thoughts on AG1 Next Gen

AG1 Next Gen is our pick for the best greens powder for muscle growth because it includes nutrients that can impact your training: calcium, magnesium, selenium, B vitamins, and more. It’s the perfect way to bridge the gap if you’re not meeting your macros through food alone. AG1 Next Gen also has plenty of B complex vitamins, which can help convert food into usable energy, helping you to push further and longer throughout your workouts.

Kayla tested AG1 Next Gen, rating it a 5 out of 5 for her first impressions. The instructions for AG1 are straightforward and easy to follow, according to Kayla. “The directions state mixing one scoop with 8-10 ounces of cold water,” she said. “The text is clearly printed and easy to spot on the packaging. The font size is large enough to read without straining, and the layout is easy to read.” She rated AG1 Next Gen a 5 out of 5 for ease of following instructions.

Using a shaker bottle, Kayla mixed one scoop of AG1 with about 10 ounces of cold water and shook for 60 seconds. “This product by far has the best solubility out of all the greens powders I have tried,” she said.

“There are now hints of vanilla sweetness that help soften the greens flavor,” Kayla noted, adding that it didn’t taste overly sweet, despite a little lingering stevia flavor. “There’s no strong bitterness and the drink is well balanced,” she said. Kayla found the mouthfeel to be smooth and light, and the texture is closer to a light juice than a thick smoothie, making it easy to drink quickly. She rated the taste a 5 out of 5.

Overall, Kayla is happy with the new formulation of AG1. “AG1’s new Next Gen formula keeps the great taste and convenience I love, but now packs in clinically studied probiotics, more bioavailable vitamins, and extra minerals to close nutrient gaps,” she said.

Best Amino Acid Supplement for Muscle Growth: Transparent Labs BCAA

Our Thoughts on Transparent Labs BCAA

Transparent Labs BCAA is our pick for the best amino acid supplement for muscle growth, because it includes eight grams of BCAAs in the optimal 2:1:1 ratio, plus 5 grams of glutamine and added electrolytes from coconut water powder. We think this BCAA supplement targets recovery, endurance, and hydration better than competitors.

Pete tested Transparent Labs BCAA, rating it a 5 out of 5 for his first impression. “The product comes in a small white plastic tub with a screw top lid that opens and closes easily. The off-white label features a dark blue text that’s simple and easy to read. It comes with a scoop for easy measuring. While the container is compact, it’s still a bit too bulky to be considered travel-friendly,” he said.

He found the instructions relatively easy to read and follow, rating them a 3 out of 5. It says mix one level scoop with 10 to 12 ounces of cold water or any beverage of your choice 30 to 45 minutes before, during, or immediately after training. For optimal results, the instructions say to consume at least two servings per day, not exceeding four servings per day.

Mixability was smooth; Pete rated it a 5 out of 5. “The product dissolved fully in 60 seconds, and no further shaking was required.” He loved the flavor that he tested. “I tested the strawberry lemonade flavor, and I think they did a great job capturing the strawberry lemonade flavor profile. However, I wasn’t a huge fan of the overall taste due to the strong stevia aftertaste, which really stood out to me. That said, the drink itself is light and refreshing, and would be easy to sip during a workout,” Pete said, rating the taste and sweetness level both 3 out of 5 (for the latter, that indicates a middle-of-the-road sweetness).

After examining the ingredient list and testing it himself, Pete thinks this supplement is a good option for athletes focused on post-workout recovery and preserving lean muscle mass, especially when training multiple times per day.

Best Multivitamin for Muscle Growth: Legion Multivitamin

Our Thoughts on Legion Multivitamin

Legion Multivitamin is our pick for the best multivitamin for muscle growth because it includes unique ingredients not found frequently in other multivitamins. Legion’s Multivitamin has ashwagandha, which may help lower stress and cortisol, helping you to sleep better and have better strength and endurance. The multivitamin also has CoQ10 and alpha‑lipoic acid, which helps to support energy production and reduce oxidative stress.

Pete tested Legion’s Multivitamin, rating his first impression and ease of reading the instructions both a 5 out of 5. “The large bottle and detailed labeling shows this is a robust and well-dosed supplement,” he said. 

The capsules themselves are clear with a light-yellow powder inside. Pete rated swallowability a 1, writing: “The recommended serving size is 8 capsules per day which is a lot.” He commented on the impracticality of taking 8 daily and found the bottle too big for travel. There was “no taste,” earning it a taste rating of 3.

Pete didn’t experience any side effects, rating it a 5 out of 5 in that category. Though overall, he said, “It’s fairly expensive, and the eight-capsule serving size is a lot to take on a daily basis.”

That said, we think Legion Triumph is great for men seeking maximal nutrient coverage who don’t mind having to take multiple pills. The brand also has a multivitamin formulated for women, too. 

Best Mass Gainer Supplement for Muscle Growth: Nutricost Mass Gainer

Our Thoughts on Nutricost Mass Gainer

Nutricost’s Mass Gainer is our pick for the best mass gainer for muscle growth because it has over 50 grams of protein per serving, and just over 1,200 calories. It’s available in three flavors and has no added fillers or ingredients. The carbohydrate source is maltodextrin, which is common in mass gainer supplements. Maltodextrin is rapidly absorbed by the body, making this supplement ideal for post-workout recovery. It’s also our pick for the best budget supplement for muscle growth, especially compared to other mass gainer supplements–Nutricost is known for being budget-friendly.

Pete tested this product and rated it a 3 out of 5 for first impressions. “Nutricost’s Mass Gainer supplement comes in a large plastic container with a net weight of nearly seven pounds. The label is straightforward and easy to read, clearly showing the calorie count and protein per serving. This comes in a pretty large container, but the lid is easy to open and close,” Pete said.

The serving size is three scoops, which filled Pete’s shaker bottle about halfway with powder, and after adding water and shaking for 60 seconds, there were still large chunks of unmixed powder. “For this mass gainer supplement, I would recommend blending for a smooth consistency and using more than the suggested 24 ounces of water unless you like a thick shake,” Pete said. 

Of the mixability of Nutricost’s Mass Gainer, Pete said: “I tried using my large 32-ounce shaker bottle to mix this mass gainer and it just wasn’t practical.”

Pete loved the taste of this mass gainer, rating it a 5 out of 5. “I tested the chocolate peanut butter flavor, and it tasted great. I was able to taste both the chocolate and peanut butter flavors, and the shake had a smooth and creamy consistency after blending,” he said. 

Our tester found the instructions produced a shake that was a little too thick for his liking and suggested some modifications: “If I was to use this supplement daily, I would use more water, about 28 to 32 ounces to make a thinner shake. I did really enjoy the flavor, and this would be something I would drink regularly,” he said.

Pete also noted that he didn’t experience any digestive issues or negative side effects after consuming this product, adding: “I was full after the full three-scoop serving size and it was a good two to three hours before I was hungry again for another meal.”

Want to compare the best mass gainers? We’ve rounded up our favorites.

How We Tested and Selected the Best Supplements for Muscle Growth

We tested and evaluated the best supplements for muscle growth, scoring them on a scale of 1 to 5 for factors such as first impressions, easy-to-follow directions, taste, mixability, side effects, and value. Our testers consider products based on their own experiences and preferences. We then review their testing feedback and data to share our findings and recommendations.

Formula

We work with a registered dietitian (RD) during testing to find the most effective and safe supplements, including greens powders, pre-workouts, and more. We look for products that are third-party tested and made without artificial sweeteners and other additives.  

Taste and Texture

Flavor is a big part of our testing process. We ask our testers to provide feedback on the taste, texture, and pleasantness of the flavor for each supplement. We rate sweetness on a scale of 1 to 5, based on sweetness strength. A score of 5 is best-tasting, 1 is not sweet at all or unflavored.

We also consider texture, and ask our tester to record any grittiness, clumps, frothiness, or conversely, smoothness and creaminess, when tasting a powdered drink.

Mixability 

When mixing a supplement powder into liquid, we prepare the product exactly as advised by the brand. We then pay close attention to how well the powder dissolves, wanting to avoid grittiness in the taste and odd textures, like chunks.  

Third-Party Testing

Third-party testing involves independent verification of safety, purity, as well as nutrition label accuracy. This helps ensure that the label on the product is accurate. Third-party testing also checks for harmful substances such as heavy metals, pesticides, and more for safety.  

The FDA (U.S. Food and Drug Administration) does not regulate supplements, so it’s vital to have independent testing done to ensure safety, accuracy, and quality.  

Value

When considering value, we place a higher value on brands that source their ingredients in America and have certifications, such as Informed Sport.

How to Find the Best Muscle Growth Supplements for You

The best muscle growth supplement for you is one that matches your goals, fitness routine, lifestyle, and budget. Here are some aspects to consider when shopping.

Your Fitness Goals

Think about what your workout or athletic goals are, which can help influence the type of muscle growth supplement that you get. You may consider pairing creatine and protein for strict gains. If you’re aiming for recomposition, you might try adding carbs, electrolytes, or supplements that help with recovery. 

Flavors

It’s vital to choose a supplement flavor that you genuinely enjoy, because sipping it regularly makes it easier to meet your goals and stick to your routine. A tasty flavor also ensures your supplementation feels more like a treat than a chore, which will support you with consistency and satisfaction long-term. You may also consider an unflavored supplement if you’d like to stack several together, or if you want to avoid flavor altogether.

Formula

Everyone has their own dietary needs, so be sure to look at the formula of the muscle growth supplement before purchasing. Also think about checking the nutrients that you may already be getting from food or a multivitamin. It’s good to make sure you’re not going above your recommended daily value (RDV) of any particular vitamin or mineral.

Cost

Muscle growth supplements can be expensive, so you may want to consider your budget when selecting a product for everyday use. Cleaner formulations, meaning those without artificial sweeteners or additives, may cost more because of their higher quality and ingredient sourcing.

Third-Party Testing

Third-party testing independently verifies the safety, purity, and label accuracy of protein powders since the FDA doesn’t regulate supplements. This process helps protect you from mislabeling, contamination, and banned substances, building trust, and ensuring that you can use products with confidence. 

Benefits of Supplements for Muscle Growth

When used along with exercise and eating whole foods, supplements for muscle growth can make a real difference. Here are a few benefits:

• Hit goals: A muscle growth supplement can help you hit your protein macros for the day with ease.
• Support strength: Muscle growth supplements like creatine can increase the intensity of your workouts and help your muscles adapt to heavier weights or more reps.
• Improved recovery: Supplements with amino acids can help repair your muscles so you can come back stronger each workout.
• Close nutrient gaps: If your diet isn’t quite getting you where you want to be, muscle growth supplements can help your overall health.

What to Avoid in Supplements for Muscle Growth

Not every muscle growth supplement is safe to use. Here’s what to avoid when shopping:

• Proprietary blends can mask what is in the supplement and how much, making it difficult to know what you’re really putting into your body.
• If a product is not third-party tested, it’s not necessarily trustworthy—especially if you undergo drug testing. 
• Unrealistic claims like overnight gains are something to be wary of. These promises generally come at a cost and are not helpful shortcuts.

Frequently asked questions

What supplement is best to build muscle?

Getting the right amount of protein is one of the best ways to help build muscle. Our pick for the best protein supplement is Transparent Labs 100% Grass-Fed Whey Isolate because it contains 28 grams of protein per serving, sourced from grass-fed cattle. The brand is third-party tested and incredibly transparent, posting their COAs on page. This product is also Informed Choice and Informed Sport certified, so athletes and gym-goers alike can build muscle while trusting the purity and safety of this protein powder. It also tastes good, too!

What increases muscle size fast?

The fastest way to increase your muscle size comes from a combination of lifting heavy weights, typically around four times a week, while also eating enough calories and protein to support growth.

What’s the strongest muscle building supplement?

Supplementing with creatine along with resistance training (lifting weights) is the most proven way to build strong muscles.