Best Muscle-Building Stack

Building muscle is supposed to be a simple equation. You lift weights and eat more than maintenance calories, and the muscle should grow. But it doesn’t always work this way. Multiple factors can get in the way of success in the gym, from the quality of the food you’re eating to your genetics.

That’s why so many people looking to put on and retain muscle will turn to supplements that can give them an edge. And multiple clinical studies confirm that supplementation with protein, vitamins, specific amino acids, and more can help you get more gains out of the same amount of work in the gym.1 However, one supplement or protein powder on its own might not be enough, especially when you consider that different ingredients work best at specific times around your workout.

Muscle-building stacks account for this by breaking up vital nutrients into pills and drinks you consume at various points throughout the day. This allows you to maximize each benefit and lets the supplements work together to achieve desired results.

If you’re a little pressed for time, here’s a quick rundown of our favorite muscle-building stacks.

At Innerbody Research, we extensively test each health service or product we review, including muscle-building stacks. No one on our testing team is a professional bodybuilder or fitness model, but we try to exercise and eat well. Incorporating these products into our lives, even for a short while, allows us to report back to you about things like taste and efficacy, albeit at a subjective, anecdotal level.

But rather than just try the products and tell you if we liked them, our team also spent nearly 1,000 hours poring over hundreds of research papers looking into the various ingredients found in these stacks. That knowledge base, combined with our personal experience, makes this a review you can actually trust.

Additionally, like all health-related content on this website, this review was thoroughly vetted by one or more members of our Medical Review Board for accuracy. We’ll keep tabs on these supplements as they evolve and keep trying them for ourselves to make sure this guide stays current.

Over the past two decades, Innerbody Research has helped tens of millions of readers make more informed decisions about staying healthy and living healthier lifestyles.

Choosing the right muscle-building stack for you depends on several factors. Here are the criteria we paid the closest attention to when making our selections.

Effectiveness

Winner: Transparent Labs

In addition to our testers’ experience, we looked at the specific ingredients and doses available from a given stack to determine its potential for effectiveness. We carefully compared those ingredient lists to available clinical research that could support their efficacy and sought to exalt only the combinations that stood the best chance of success for most people.

But that success might look different depending on your particular goals. Some might want to put on as much mass as possible, even if some fat comes along. Others would want to simultaneously build muscle and lose fat — a difficult balance, to be sure. This is one of the reasons that we regard Transparent Labs as our best overall pick, as it offers more than a dozen stacks tuned to various specific goals.

There are other caveats to effectiveness for some consumers, as well. For example, whey is generally a better tool for adding bulk than pea protein, but whey isn’t an option for vegans. Caffeine is another divisive ingredient in pre-workout supplements among those with a sensitivity. Again, Transparent Labs offers vegan and non-vegan muscle-building stacks, as well as stimulant-free versions for many of its popular combinations.

Swolverine makes sense as a runner-up in this category, as the company also offers a few different stacks. Its Performance Series stack is especially effective from a recovery standpoint, as it boasts one of the best sleep aid components we’ve come across.

Cost

Winner: JYM

The range of costs among muscle-building stacks isn’t particularly wide, especially among the high-caliber options we’ve included here. There are certainly those with lower price tags, but that’s not where our examination stops. We also look at things like potential bulk or subscription savings, shipping costs, and money-back guarantees or return policies.

At just $135 for the JYM System Stack, JYM is an undeniable winner for cost. You can tweak the sizes of your protein powder tub and pre-workout container to save a little more money in the long run, too. The company sets its free shipping threshold at $110, so shipping is free. Orders also come with free ebooks that you’ll receive via email — one devoted to burning fat and the other to building muscle. Calling them ebooks might be a stretch, given that the longer of the two is only about 15 pages, but it's a useful extra tool that’s worth mentioning when you look at what you get for your money.

The other three companies in this guide all have price points closer to the $200 mark, with several reaching beyond that. Many of Transparent Labs’ stacks start a little above that $200 point, but you can bring the cost down by signing up for automatic billing and shipments.

Safety

Winner: Transparent Labs

Compared to taking steroids (which is not advised), most muscle-building stacks are incredibly safe. But some are still safer than others. One important factor we look for is third-party testing. This ensures that any given supplement contains exactly what the company says is in it, with no contamination or dilution.

Another way we evaluate safety is by comparing a supplement’s ingredients to available clinical data on adverse reactions. Sometimes these reactions are dose-specific or have particular contraindications with prescription medicines, and we use this information to weigh the potential risk any given supplement poses.

Transparent Labs goes further than most other companies by subjecting its products to third-party testing and releasing those batch-specific results to the public. You can compare the lot number printed on any product you receive to a long list on the company’s certificates or analysis page. That will lead you to results detailing purity, dose accuracy, heavy metal content, and more.

One last thing we appreciate about Transparent Labs is that it’s the only company in our guide to keep sucralose out of all its flavored drinks. Sucralose has been linked to things like increased tumor formation in some animal studies.2 There’s also evidence that it produces negative disturbances in gut bacteria.3 These studies typically use much higher concentrations than you’d find in everyday products, and they were conducted mostly in animals, but they are worrisome, to say the least.

Taste

Winner: JYM System

By ordering these products for ourselves, we can let you know one of the most important things you’ll want to consider before buying them: how they taste. Granted, this is ultimately a subjective measure, but there were some unanimous findings among our testers that could easily sway your decision.

Of the companies on our list to offer pre-workout and post-workout drink mixes that are not protein powders, JYM and Swolverine sweeten some of their flavored mixes with sucralose, though JYM offers its pre- and post-workouts in alternatives that contain only natural flavors and sweeteners. Specifically, these contain erythritol, cane sugar, or stevia, depending on the flavor and formula. But those natural alternatives aren’t part of the flavor options for stacks at the moment, even though JYM charges the same amount for them on the individual products’ pages. (We’ve been told that these alternatives will eventually be part of the stack options, but no date for this has been set.)

On the protein powder side, JYM’s Rocky Road was a runaway winner. If you prefer something a little less flavorful that you can add to a smoothie without overwhelming it, Swolverine is the way to go, but JYM’s Rocky Road Ultra-Premium Protein Blend was outstanding. Transparent Labs makes a protein powder that’s tasty in its own right, but you could tell that it would be best mixed with a milk of your choosing. We tested these protein powders with plain water, and JYM’s stood on its own.

Let’s dive deeper into the Rocky Road example because it illustrates JYM’s obvious attention to how its products taste. The first winning attribute was its ability to taste great in plain water. That allows you to save both money and calories if you desire, or you can mix it with milk or almond milk for an even more robust flavor. The flavor itself was actually nuanced. There aren’t any nuts in the mix, but Rocky Road is supposed to have nuts in it, and yet this protein powder actually provides a hint of that nutty flavor in the background. Our testers agreed it tasted more like walnut than any other nut.

The last reason we liked JYM’s protein powder so much is a fun one. It contains little marshmallows, a traditional Rocky Road ingredient. These are like the marshmallows you’ll sometimes see in hot chocolate packets, and they taste like the marshmallows in Lucky Charms cereal. What’s impressive about the whole mix, though, is that each scoop contains just 2g of sugar. That’s thanks to the use of sucralose, which somehow doesn’t give the mix the artificial taste typically associated with the sweetener.

If you’re looking to avoid sucralose for health reasons, JYM makes a naturally flavored and sweetened version of its protein powders, but like the pre- and post-workouts, these aren’t part of any stack yet. Your best bet, for now, would be to go with Transparent Labs, whose protein powder has a much simpler ingredient list and only uses stevia for sweetness. It tastes good, too.

Convenience

Winner: Transparent Labs

Convenience in a muscle-building stack comes from a handful of places. It starts with a company’s website, ease of use, and customer consideration. Simple navigation, money-back guarantees, and privacy policies also play into this category. Flexible subscription options are also a big plus when available.

Taking a given supplement stack needs to be convenient, as well. Complicated dose timing can be prohibitive for a busy lifestyle, so fewer pills and drinks and more convenient times each day can make a big difference.

Transparent Labs offers the widest product variety in its stacks, convenient live chat support, and relatively fast shipping, though JYM had the fastest shipping times of the companies from which we ordered. Its subscriptions allow you to choose your delivery schedule from 30, 45, or 60 days, so you can consume the product at your own exercise pace and not worry about remembering to reorder when you’re getting low.

To give you a quick overview of how our top muscle-building stacks compare to one another, we’ve put together this chart outlining their costs, supplement quantities, and protein types.

To create muscle-building stacks, companies identify various supplements that can improve workout performance and boost results, combining them into an effective system. Instead of taking everything at once, you might take a daily vitamin supplement in the morning, a pre-workout before heading to the gym, and a protein powder or recovery aid after your lifting session.

Here’s a look at the types of supplements included in various muscle-building stacks and some of the ingredients you’re likely to find in them.

Daily supplements

These are supplements you’ll take daily to provide your body with vitamins, minerals, amino acids, and other elements that studies show can improve performance in the gym and during recovery afterward. In many studies, the ingredients in these supplements are associated with greater muscle mass gains after a training period.

Common ingredients in daily muscle-building supplements include:

• Vitamin B complex
• Vitamin D3
• Omega 3s
• Zinc
• Chromium

Pre-workouts

Pre-workouts are usually drinks that include ingredients to do one of two things. Either they help give you more energy in the gym so you can perform at your best, or they help protect your muscles from catabolism. That means your body won’t target your muscles for energy and potentially undo your hard work.1

Common ingredients in pre-workouts include:

• Branched-chain amino acids (BCAAs)
• Beta-alanine
• L-citrulline malate

Post-workouts (recovery)

Recovery supplements also often come in the form of drinks. They’re occasionally combined with your protein supplements but also regularly exist on their own. Like pre-workouts, their ingredients — like BCAAs — guard against catabolism, but they also provide your body with carbs to replenish glycogen stores spent during your training sessions.4

Common ingredients in post-workouts include:

• BCAAs
• Glutamine
• Creatine
• Betaine
• Chromium

(If you’re interested, we’ve got complete, separate guides to BCAA and creatine supplementation for women, too.)

Protein powders

If you want to build muscle, you have to get enough protein. For many, that means supplementation, as few of us have the time to prepare enough calorically dense, protein-rich meals every day. When bulking, you want a calorie-rich protein powder that offers a complete amino acid profile. This is why you’ll rarely see vegan offerings that contain only pea protein, which is less bioavailable than whey protein. Some pea protein supplements will often include a secondary protein to round out the amino acid profile, but pea protein does contain all 9 essential amino acids.

Common protein powder ingredients include:

• Whey protein
• Pea protein
• Rice protein
• Pumpkin seed protein

Testosterone boosters

In many men, an inability to put on muscle is tied to lower testosterone levels. In clinical studies, various ingredients found in testosterone boosters have been shown to increase testosterone. Even if you don’t have clinically low testosterone, a boost might help give you an edge in muscle repair and production.

Testosterone booster ingredients include:

• D-aspartic acid
• Zinc
• Ginseng
• Fenugreek
• Magnesium
• Vitamin D3

If you think low testosterone could be the cause of your struggles in the gym, you can find out what your T levels are without leaving your house. Check out our complete guide to at-home testosterone testing for more.

Anyone looking to get the most out of their efforts in the gym may benefit from a muscle-building stack. Many already use one or more of these supplements, just not in combination. Some grab a pre-workout for an added boost in the gym or enjoy a protein shake afterward. But since buying a stack will often save you money compared to buying the supplements individually, the increase in cost to upgrade to a full stack is nominal.

So, if you use any kind of supplement in the hopes that it will increase your effectiveness in the gym and the gains you see from your hard work, it might be well worth your while to use a stack instead.

Those working out primarily to lose weight might not find certain muscle-building stacks as beneficial as others. Ingredients like creatine can cause water retention, and protein powders and mass gainers may contain more calories than you’d like to consume in a given day. Pre-workout supplements that don’t contain creatine and lower-calorie protein powders can still play a role in weight loss, but you’d probably do better either buying these things on their own or looking for a company — like Transparent Labs — that sells fat-burning stacks. It is important to consult a qualified healthcare provider before trying any new supplement.

Best overall, best stim-free, and best vegan option

As the company’s name suggests, Transparent Labs wants its processes and ingredient quality to be as visible as possible. To that end, it employs third-party testing and provides certificates of analysis and composition through a batch-specific database on its site.

Transparent Labs also offers one of the most diverse selections of bulking stacks on the market, with vegan and stim-free options available. It also has a stack dedicated to mass-gaining that’s especially useful for people genetically predisposed to struggling to gain weight. It’s not an ideal choice for everyone, given its caloric content, as there is a risk of gaining fat alongside muscle. Still, it’s a good option to offer; neither Swolverine nor Jym offers a similar stack, despite Jym having a mass gainer drink in its lineup.

Here’s a quick breakdown of its contents and pricing:

Compared to our last evaluation of Transparent Labs stacks, the company has slightly increased its cost per stack on the subscription side. One-time purchase costs have remained mostly the same, amounting to a reduction in the discount you’d get for subscribing.

Protein powder

Transparent Labs’ whey protein powder is 100% grass-fed, which means that the milk it uses is more likely to have a better balance of nutrients and a lower likelihood of causing inflammation.5 It provides 28g of protein and is available in:

• Vanilla Oatmeal Cookie
• Milk Chocolate
• Dark Chocolate
• Strawberry
• Chocolate Peanut Butter
• Vanilla Peanut Butter
• Peanut Butter
• French Vanilla
• Mocha
• Cinnamon French Toast (new)
• Oatmeal Chocolate Chip Cookie (new)
• Unflavored

The organic vegan alternative offers 24g of protein, is made from pea and rice protein, and only comes in chocolate or French vanilla. The Mass Gainer powder is a more potent protein powder and meal replacer, with 53g of whey protein and 750 calories per serving. It comes in French vanilla and chocolate glaze donut flavors.

Pre-workout

You’ll find Transparent Labs Bulk pre-workout in many of the company’s stacks, but not its stim-free Muscle Building Essentials stack. The disparity between the standard and stim-free pre-workout formulas is a bit of a disappointment when you compare them side-by-side. One might hope that a stim-free formula would simply remove caffeine and other stimulant ingredients and leave the rest of the components intact. But in its stimulant-free alternative, Transparent Labs also removes much of the vitamin content from its Bulk pre-workout.

Both formulas contain some of the most important ingredients the company offers in a pre-workout, including:

• Citrulline malate: 6,000mg
• Beta-alanine: 4,000mg
• BCAAs: 4,000mg
• Betaine: 2,500mg

Another way that the Bulk and stim-free pre-workouts differ is in their flavor options. The caffeinated Bulk formula is available in:

• Sour Grape
• Watermelon
• Green Apple
• Orange
• Blue Raspberry
• Strawberry Lemonade
• Piña Colada
• Strawberry Kiwi
• Lemon Lime
• Black Cherry
• Peach Mango

Meanwhile, the stim-free version is available in:

• Cherry Limeade
• Sour Grape
• Blue Raspberry
• Green Apple
• Orange
• Peach Mango
• Strawberry Lemonade
• Tropical Punch

Creatine and HMB

While many companies put creatine in a dedicated pre-workout, post-workout, or both, Transparent Labs isn’t prescriptive about when and how to take its creatine, which stands apart from its pre-workout. That said, the company does recommend taking it within 30 minutes of a workout for optimal results.

Transparent Labs offers one of the most generous doses of creatine among the stacks on our list, at 5,000mg. This product also contains β-hydroxy β-methylbutyrate (HMB), which has been shown to protect muscle mass and encourage growth.6 By contrast, JYM’s System only contains 4,000mg of creatine spread across two different supplements, while Swolverine’s creatine monohydrate offers 5,000mg but doesn’t include the HMB.

The creatine and HMB supplement is available in 10 flavors, as well as an unflavored variety. The 10 flavors are:

• Fruit Punch
• Tropical Punch
• Watermelon
• Black Cherry
• Blue Raspberry
• Orange
• Peach Mango
• Hawaiian Splash
• Strawberry Lemonade
• Sour Grape

Daily growth supplement

In addition to the three drinks that come with a Transparent Labs muscle-building stack, you also get its Growth supplement. These 90 capsules contain just one ingredient: phosphatidic acid (PA). This lipid messenger is known to promote muscle growth and has been shown to improve muscular performance and overall body composition in clinical studies.7

A common dose seen in PA studies is 750mg, the same amount you’ll get from each serving of Transparent Labs Growth. It’s a stimulant-free supplement, so you can incorporate it into your daily regimen wherever is most convenient.

Taste and mixability

Transparent Labs’ protein powders are our second favorite of the options in this guide — second only to JYM in terms of taste and mixability. We found the balance of flavors in its Chocolate Peanut Butter blend to be spot-on; both aspects provided a strong taste without overpowering each other.

For its pre- and post-workout mixes, Transparent Labs is right around the top, more or less tied with JYM in flavor and mixability. One big caveat here is that several of the supplements included in Swolverine’s stacks are one-off ingredients like creatine or beta-alanine, and they mix into water exceptionally well compared to more complicated pre- and post-workouts.

Ultimately Transparent Labs is a safe bet if you're concerned at all about flavor, and the fact that it doesn’t use sucralose in any of its formulas is a big benefit, in our opinion.

Shipping and returns

Shipping from Transparent Labs is free on orders over $100, so all of its muscle-building stacks qualify.

If you aren’t satisfied with the product, you can return it within 30 days, but opened products don’t receive money back. Instead, they get store credit.

Best budget pick and best-tasting

JYM has an impressive array of supplements that aim to improve your fitness, performance in the gym, and recovery. It doesn't have quite the same variety among muscle-building stacks that some of its competitors do, with just one stack dedicated solely to muscle growth in its lineup. That said, the component in the JYM System stack might make it a better choice for muscle growth than the company’s dedicated muscle builder. This depends a little bit on your diet apart from the stack.

JYM’s muscle-building stack consists of a protein powder, pre- and post-workouts, and a fish oil supplement. It costs $143.96. Its System stack contains a protein powder, pre- and post-workouts, and a fast-absorbing high-glycemic carbohydrate drink. It costs $134.96. Shipping is free on domestic stack orders.

If you eat a healthy, high-protein diet that contains foods like wild-caught salmon, sardines, and anchovies, you may not need the fish oil supplement. And consuming high-glycemic carbs after an intense workout has been shown to improve sleep and overall recovery.8

You can get the protein powder and pre-workout in two sizes. The price points above reflect the smallest sizes of each, which should work out to roughly one month’s worth.

Let’s look at each component in the stacks to better understand what JYM has to offer.

Pro JYM Protein Powder

You can get JYM’s protein powder in 2lb or 4lb jars, depending on your needs. One 2lb jar delivers 24 servings, which is enough if you only consume it around workouts. If you want to supplement your daily protein intake, you might want to opt for the larger jar. It comes in seven flavors, including:

• Cookies and Cream
• Banana Bread
• Chocolate Peanut Butter
• Rocky Road
• Chocolate Mousse
• Tahitian Vanilla Bean
• Strawberry Milk

There used to be a Root Beer Float flavor, as well, but that has been removed from the catalog.

JYM is currently in the process of modifying its protein sources to eliminate its egg white protein. At the moment, which flavor you buy will determine which protein blend you receive. Either way, JYM protein powder still contains 24g of protein, ensuring both a complete amino acid profile and a variegated absorption rate. That makes it less crucial to consume within a set time from your workout, as your body will digest these proteins at slightly different speeds. The original blend that’s being phased out is:

• Whey protein isolate: 7.5g
• Micellar casein: 7g
• Milk protein isolate: 7g
• Egg white protein: 2.5g

As of this writing, the Chocolate Brownie flavor offers the new protein profile:

• Whey protein isolate: 8.5g
• Micellar casein: 7.75g
• Milk protein isolate: 7.75g

The company did not provide us with a timetable for the rest of the conversions.

Pre JYM High-Performance Pre-Workout

JYM’s pre-workout provides plenty of energy to get you through a training session. The lion’s share of that boost might come from the 300mg of caffeine in each serving. Considering that JYM doesn’t offer a non-stim option, this seems like more caffeine than necessary for most lifters. And anyone sensitive to stimulants will be out of luck.

The highlights of JYM’s pre-workout ingredient list include:

• Citrulline malate: 6g
• BCAAs: 6g
• Creatine HCl: 2g
• Beta-alanine: 2g
• Betaine: 1.5g
• Beet root extract: 500mg
• Caffeine: 300mg
• Alpha-GPC: 150mg
• Huperzine A: 50mcg
• BioPerine: 5mg

While nearly all of these ingredients should help boost energy levels, provide enough of a push to gain a rep or two per set, and promote muscle preservation, the BioPerine is one of the most interesting. It’s there to increase the bioavailability of the rest of the ingredients so your body absorbs them more thoroughly.9

You can get JYM’s pre-workout in 20- or 30-serving tubs in the following flavors:

• Tangerine
• Grape Candy
• Pink Lemonade
• Rainbow Sherbert
• Pineapple Strawberry
• Black Cherry
• Strawberry Kiwi
• Raspberry Lemonade
• Cherry Limeade
• Orange Mango

Post JYM Recovery Matrix

JYM’s post-workout has a few of the same ingredients you’ll see in its pre-workout, as well as a handful that can help speed up recovery and promote muscle growth. The list includes:

• BCAAs: 6g
• Glutamine: 3g
• Creatine HCl: 2g
• Beta-alanine: 2g
• L-carnitine L-tartrate: 2g
• Betaine: 1.5g
• BioPerine: 5mg

JYM’s post-workout contains enough powder for 30 servings, and it’s available in seven flavors:

• Blue Arctic Freeze
• Lemonade
• Mandarin Orange
• Rainbow Sherbet
• Green Apple Gummy
• Fruit Punch
• Watermelon

Post JYM Dextrose Carbs

It might seem strange to drink such a sugary beverage right after putting in a lot of work at the gym, but if your primary goal is building muscle and you work hard enough to burn the associated calories, you could see some significant benefits from doing so. Specifically, this works when it’s a high-glycemic index drink. That means it gets into your system quickly. It’s the opposite of what you’d want if you‘re diabetic, but if you have a healthy sensitivity to insulin, you should be okay.

Studies suggest that high-glycemic-load carbs consumed after an intense workout can be a boon to recovery. Specifically, they can help prevent the more energizing aspects of good gym work from interfering with your sleep. And if you’ve completely raided your muscles’ stores of glycogen through a lifting session, this can replenish them quickly, allowing you to maintain greater strength in future workouts throughout the week.

Dextrose is the primary ingredient here, delivering a 29g dose of sugar. The supplement is available in the following flavors:

• Blue Arctic Freeze
• Lemonade
• Mandarin Orange
• Rainbow Sherbet
• Green Apple Gummy

Omega JYM

Given the multitude of potential benefits your body can reap from omega-3s — especially in the gym — it makes a lot of sense for a company like JYM to include an omega-3 supplement in its stacks.10 And this fish oil-derived option includes the three main omega-3s — DHA, EPA, and DPA. The company packs a lot of each into its capsules, so the serving size is just two pills twice daily.

Here are the measurements of each omega-3 in Omega JYM:

• DHA: 1,500mg
• EPA: 1,500mg
• DPA: 300mg

This supplement is part of the JYM Muscle Building Stack but not the System stack. We think both are good choices, but we prefer the combination of the System stack with a healthy, protein-rich diet including lots of fish.

Taste and mixability

Taste was our favorite aspect of JYM’s offering, particularly its protein powder. We weren’t terribly impressed by its pre- and post-workouts, but they were more or less on par with similar products from other companies.

But the protein powders mixed wonderfully into plain water and had rich, complex flavors. They were most enjoyable!

JYM takes extra steps to make them taste so good. Take, for instance, the small, hard marshmallows in the Rocky Road flavor. Like the marshmallows in a good hot cocoa mix, these were firm enough to stay intact after 15 seconds of intense shaking in a shaker cup.

Shipping and returns

JYM offers free shipping on all orders over $100. That means its muscle-building stack will ship to you for free. The return policy is a little more convoluted. JYM claims that it wants your search for the right supplements to be hassle-free and that it’ll help you if you’re unsatisfied with a product. It doesn't say how much time you have to make such a claim or exactly what it’ll do for you in any specific situation.

Best for recovery

As a company, Swolverine is all about enhancing athletic performance. It has an impressive supplement catalog that includes products designed for muscle building, fat loss, performance improvement, and even gut health.

Swolverine makes a point to be as transparent as possible.

• It doesn't employ proprietary blends.
• It offers certificates of analysis on all its supplements.
• It designs ingredient-specific stacks that allow you to know for sure whether a given product is working for you (and why).

Swolverine offers three muscle-building stacks, two of which are fully vegan. All three are stimulant-free. Here’s a look at how they differ in cost and contents:

Depending on whether you go for the vegan or non-vegan Build stack, you’ll either get whey protein (non-vegan) or a combination of pea and pumpkin seed protein (vegan). That’s because pea protein doesn’t offer as bioavailable an amino acid profile. Adding pumpkin seed protein ensures you get more bioavailability and all the amino acids your body needs to build healthy muscle.

The Performance Series protein powder clearly has less protein than the two build stacks, so you might want to make sure you’re getting extra protein from elsewhere in your diet. But that powder isn’t billed as a protein powder specifically. Swolverine considers it a post-workout blend that offers protein in conjunction with a moderate carbohydrate load from pea starch and several other useful ingredients we’ll explore below.

Supplement stack

Both vegan and non-vegan Build stacks come with identical components beyond the protein powder. You can mix all of these in a single drink to consume before or during a workout, though Swolverine recommends additional L-glutamine after your workout to optimize recovery (which is one of the reasons you see L-glutamine in the Performance Series Post drink). Here are the four included supplements in the Build stacks:

• Beta-alanine (5,000mg): A non-essential amino acid
• L-citrulline malate (5,000mg): A non-essential amino acid combined with malic acid
• L-glutamine (5,000mg): A conditionally essential amino acid
• Creatine Monohydrate (5,000mg): micronized creatine, which is a combination of arginine, methionine, and glycine.

Performance Series stack

Swolverine’s Performance Series stack is our preferred stack in its lineup, thanks to its emphasis on recovery support. There are certainly ingredients in the Build stacks that promote recovery, but the Performance Series takes this to another level. That includes a pre-workout and an intra-workout supplement. The pre-workout contains a high dose of citrulline malate, which has been shown to increase nitric oxide levels to improve exercise performance and also has some research into its ability to reduce muscle soreness afterward. There’s also L-carnitine to guard against muscle loss during intense cardio and coconut water powder to promote hydration and protect renal health.

Swolverine’s Intra intra-workout supplement is relatively uncommon among muscle-building stacks, as well. The other companies on this list all provide pre-workouts, and many of those can be taken during your workout if you like, but none of them are designed specifically for consumption in the middle of a session. It contains all nine essential amino acids, including the three branched-chain amino acids. It also offers a 2.5g blend of ingredients the company claims are there for hydration and endurance, but there’s limited evidence behind the endurance side of that claim.

Crucial to our regarding the Performance Stack as your best choice for recovery support is the included ZMT supplement. Swolverine ZMT contains ingredients designed to promote deep, restful sleep, which is essential for muscle recovery.22 It also plays a role in fat loss and overall mental health.23 24 No other stack in this guide offers a product focused on improving sleep.

Here’s a quick look at the full list:

• Vitamin B6: 25mg
• Magnesium: 422mg
• Zinc citrate: 50mg
• L-Taurine: 1,000mg
• L-Theanine: 500mg
• L-Tryptophan: 500mg
• Ashwagandha Root Extract: 300mg
• GABA: 100mg
• Valerian Root Extract: 100mg
• Tongkat Ali Root Extract: 50mg
• Rhodiola Rosea Root Extract: 50mg
• DIM (3,3'-Diindolylmethane): 50mg
• BioPerine: 5mg
• Melatonin: 3mg

Melatonin on its own is typically enough to get most people off to sleep,25 but combined with valerian root and L-tryptophan (each of which affects your serotonin levels), it becomes a powerful sleeping aid.26

ZMT also includes ingredients that may help normalize testosterone levels, including ashwagandha and zinc. Its zinc choice may be particularly effective; zinc citrate provides 31% elemental zinc, which has been shown to increase testosterone levels in clinical studies.27 That translates to more than 15mg of elemental zinc in ZMT.

The Performance Series stack also includes a vegan post-workout protein fortified with pea starch, electrolytes, and other useful ingredients. It doesn’t have quite as much protein as powders from its competitors or as much as Swolverine’s other protein powder, so you may wish to supplement your protein further. Here’s the full list:

• Pea Starch (Carb 10®): 12g
• Pea Protein Isolate: 8g
• L-Glutamine: 4g
• Bromelain: 500 mg
• Coconut Water: 500mg
• Pomegranate: 500mg
• Papaya: 500mg
• Pineapple: 350mg
• Spirulina: 250mg
• Pink Himalayan Salt: 200mg

Taste and mixability

Since we feel like the Performance Series stack is the standout here, we were eager to test it in-house for taste and mixability. In this regard, it didn’t perform quite as well as the competition. The pre- and intra-workout drinks mixed relatively well, but the intra-workout is sweetened with sucralose, whereas the pre-workout uses stevia. Why the intra-workout couldn’t also use stevia instead of sucralose is a mystery, but we typically find that sucralose imparts a vaguely artificial flavor to beverages. There are some exceptions, but this isn’t one of them.

The post-workout pea protein drink falls a little flat when mixed with plain water. Its flavors are very well balanced (we tried the chocolate peanut butter), but none of them are quite punchy enough to make us want to come back for more. And compared to the other protein powders we tried in creating this guide, this one left the barest amount of film both in the glass and on our palates. For anyone looking for a vegan stack with great recovery support, these shortcomings likely aren’t enough to put you off this option — they wouldn’t deter us — but those seriously concerned with taste might want to start elsewhere.

Shipping and returns

Swolverine offers free shipping on all US orders over $100. Its three muscle-building stacks are expensive enough to qualify for free shipping.

Swolverine’s return policy isn’t as good as some of its competitors. It gives you a 30-day window to initiate a return but doesn't accept returns on opened products. That means you can really only return something if you change your mind before even trying it out. That said, the company states that it processes returns on a case-by-case basis and that there is some leeway in certain scenarios.

Best to prevent fat gain

While CrazyBulk sells all of its various supplements individually, its site actually makes it easier to shop for stacks. The company designs several of its supplements to mimic the effects of substances that are either unhealthy or banned by competitive organizations and, in some cases, downright illegal. Its alternatives might not produce identical results, but between their proximity to these substances and their increased efficacy when stacked, you can expect some effect.

CrazyBulk’s bulking stack consists of four supplements, each in capsule form. A one-month supply of the Bulking Stack costs $184.99, but you can save if you have the capital to buy in bulk. A two-month supply comes with a free third month, costing just $369.98 for all three. That knocks the monthly cost down from $185 to $123.

The combination of supplements gets our vote for the best option to prevent fat gain for a couple of reasons. None of its supplements contain any calories. Other stacks provide calories in their pre- and post-workout drinks and protein powders. We still consider the lack of a protein powder in this stack more a con than a pro, given the role proper protein intake plays in building muscle. But it is an undeniable part of our calculus regarding potential fat production.

The supplements in this stack also contain ingredients that alter lipid metabolism, like beta-sitosterol.28 And some improve insulin sensitivity in animal models.29 Doses are much higher in these studies than what CrazyBulk provides, but the combination may be enough to see results.

Let’s take a look at each supplement in the Bulking Stack to understand what they can offer you as a whole.

Testo-Max

Testo-Max is CrazyBulk’s testosterone supplement. It contains several ingredients proven to help men improve strength training, including a generous dose of D-aspartic acid.11

By addressing potentially low testosterone levels, it should be able to help men build and maintain muscle without adding as much fat, especially if their testosterone levels are at all below normal. (It can also have positive sexual side effects, including increased semen quality and volume, stronger erections, and improved libido, though research on these benefits is mixed.)12

Here’s a look at the ingredients in Testo-Max:

• Vitamin D3 (Cholecalciferol): 52mcg
• Vitamin K1 (from Phytonadione): 20mcg
• Vitamin B6 (from Pyridoxal-5-Phosphate): 20mg
• Magnesium (from Magnesium Oxide and Magnesium Citrate): 200mg
• Zinc (from Zinc Citrate Dihydrate): 10mg
• D-Aspartic acid: 2,352mg
• Nettle leaf extract 4:1 (Urtica dioica): 40mg
• Ginseng red powder (Panax ginseng)(Root): 40mg
• Fenugreek extract 4:1 (Trigonella foenumgraecum) (Seeds): 40mg
• Boron (from Boron Citrate): 8mg
• Bioperine 95% Piperine: 5mg

Trenorol

Trenorol is marketed as a safe and legal alternative to a banned anabolic steroid called trenbolone. 13 It’s a combination of four active ingredients whose properties aim to mimic those of trenbolone without the dangerous side effects.

Those four ingredients are:

• Beta Sitosterol (600 mg): A plant sterol shown to promote muscle growth14
• Samento Inner Bark (300 mg): A woody vine that has improved insulin sensitivity in animal studies.
• Nettle Leaf Extract (300 mg): A traditional medicine that can protect the prostate15
• Pepsin (75mg): A digestive enzyme with workout recovery potential16

It’s worth noting that many of the studies looking into these individual ingredients with any degree of success use much higher doses than seen here. Theoretically, they may have a synergistic effect in combination with one another, but there is no evidence of that just yet.

D-Bal

Like Trenorol, D-Bal is designed as a safe alternative to another banned anabolic steroid: Dianabol. It employs a handful of ingredients to achieve its effects, but methylsulfonylmethane (MSM) is the most abundant and likely most important of the bunch.17 MSM has been shown to reduce muscle pain after workouts and fatigue during workouts.18 That means you’ll be able to push through more reps and still feel good afterward.

Several other D-Bal ingredients promote healthy muscle construction, and some — like ashwagandha — have benefits for testosterone levels and mood regulation, though we like to see ashwagandha doses closer to 600mg.19 Let’s take a look at D-Bal’s complete ingredients list:

• Magnesium (from Magnesium Oxide): 60 mg
• MSM: 800 mg
• L-isoleucine: 300 mg
• Suma Root Concentrated Extract 2:1 (Pfaffia paniculata): 200 mg
• Ashwagandha (Withania somnifera): 200 mg
• Tribulus Terrestris (Fruit): 75 mg
• Sodium Hyaluronate (Hyaluronic Acid): 30 mg

DecaDuro

DecaDuro derives its name from Deca-Durabolin, the brand name of a banned anabolic steroid called nandrolone. CrazyBulk uses six ingredients in this supplement that, when combined, may improve endurance and recovery time.

Ingredients like L-carnitine and wild yam can help protect muscles against catabolism,20 while citrulline can enhance performance and reduce soreness.21 Here’s the ingredients list for DecaDuro:

• Wild yam (Dioscorea opposita Thunb)(Root): 750 mg
• Ginseng (20% Ginsenosides)(Panax ginseng)(Whole herb): 375 mg
• L-Arginine alpha-Ketoglutarate: 150 mg
• Acetyl-L-Carnitine: 75 mg
• L-citrulline: 75 mg
• Tribulus Terrestris (Tribulus terrestris L.)(Fruit): 37.5 mg

Shipping and returns

CrazyBulk provides free shipping on any order to any location inside and outside the US — regardless of order size — and most US orders arrive within about a week. This is quite different from the free shipping thresholds many companies use to get you to buy more products if you don’t want to pay for shipping. The stacks in our guide all meet any free shipping thresholds their companies employ, but it’s still nice to see one of them build free shipping into its system.

CrazyBulk’s return policy isn’t quite as illustrious, however. Not only does it only accept returns on unopened merchandise, but its return window is a paltry 14 days. That means you don’t get to try the product to see if it works for you, and if you change your mind, you have to initiate a return in a hurry.