Best GNC Supplements for Muscle Building

If you’re looking for a supplement that will rapidly maximize your performance, help you lose weight, and build muscle, you’ve come to the right place. 

Aside from eating a well-balanced diet and consistent exercise, taking a muscle-building supplement can help you build muscle and reach your fitness goals faster. 

The search for the best muscle-building supplement can be a challenge. But when it comes to the best products, GNC is one of the most trusted brands in the fitness and supplement industry. They offer a broad range of products that you can choose from.

GNC believes that every person has their own definition of what it means to live well and they see it as something worth celebrating. 

Therefore, they created a supplement brand for both new and experienced fitness enthusiasts that will spark motivation and support their goals with gaining muscle. Their products are backed with ingredients such as protein, BCAAs, and many more. 

If you’re interested to know more about the best muscle-building supplements by GNC, keep reading.

5 Best GNC Muscle Building Supplements

Here are the five best GNC supplements to build muscle:

1. GNC Mega Men Sport Multivitamin 90 Count

Product Description

If you’re looking for a protein and creatine supplement that supports overall men’s health, performance, and muscle function, the GNC Mega Men Support Multivitamin is a great option. 

Mega Men Sport is a GNC product that sells premium multivitamins designed for physically active men who desire more for their bodies.

Unlike other multivitamins, every capsule of GNC Mega Men contains more antioxidant power. Its key ingredients include Beta-Alanine, a high-efficiency muscle pH buffer. It also features carnitine, which uses fatty acids as energy for your workout performance.

The GNC Mega Men is available in two different kinds of packs: one pack consists of 45 servings, while the other pack includes 90 servings. Other special ingredients that can be found are collagen, glutamine, lutein, and enough creatine.

The Mega Men Sport contains a typical creatine loading phase and is ideal for men who undergo intense weight training. Each capsule is easy to swallow and contains a robust blend of over 30 clinically studied ingredients. 

According to one study featuring 112 health volunteers, results and improvements can be seen after six weeks of taking it continuously. 

Another key component is BCAAs, which assist in muscle gains, muscle tissue, and muscle protein synthesis. This fuels and supports muscles by offering necessary electrolytes lost during intense workouts. Lastly, it is packed with antioxidants that battle free radicals produced during exercise. 


  • Easy to swallow
  • Supports overall men’s health, performance, and the function of muscle
  • Includes Beta-Alanine
  • Suitable for men who undergo high-intensity interval  training
  • Available in 45 servings and 90 servings
  • Features carnitine and BCAAs 
  • Contains antioxidants
  • Boosts muscle growth, muscle gain, and overall muscle mass


  • Not suitable for those with cancer or reproductive issues
  • Includes Titanium Dioxide

Interested? You can buy the product here! 

2. GNC Mega Men Multivitamin 180 Count

Product Description

GNC Mega Men Multivitamin 180 Count is suitable for those looking for a GNC muscle builder that provides heart, brain, prostate, and immune support. 

Compared to the Mega Sport supplement, Mega Men includes superfood fruit and vegetable sources. Some examples are orange peel powder, broccoli, and cranberry fruit powder. 

This dietary supplement also includes 180 capsules per bottle and combines a specially formulated blend of over 30 clinically studied key components to support men’s overall health. Not only that, but it also provides more than 100% of RDA, thanks to its 20 minerals and vitamins.

However, just like the Mega Men, it also includes amino acids such as L-Taurine, L-Methionine, L-Glutamine, L-Carnitine. Other components consist of Titanium Dioxide (Natural Mineral Whitener), Natural Vanilla Mint Flavor, Talc, Caramel Color, Stevia Leaf Extract.


  • Includes 180 capsules per bottle
  • Perfect for heart, brain, prostate, and immune support
  • Includes superfood fruit and vegetable sources
  • Consists BCAAs
  • Features over 30 clinically studied key ingredients
  • Includes 20 minerals and vitamins
  • Provides more than 100% of RDA
  • Supports men’s overall health
  • Boosts energy, improves stamina, and muscle growth
  • Prevents prostate soreness


  • The huge size of pills
  • Contains a p65 warning for cancer
  • Might cause nausea

Interested? You can buy the supplement here! 

3. GNC Pro Performance 100 % Whey Protein Powder in Vanilla Cream

Product Description

If you’re looking for a pure protein powder that fuels metabolism and boosts muscle growth and recovery, the GNC Pro Performance is a great choice. 

This gluten-free supplement is formulated to support men’s lean muscle recovery and support a healthy metabolism, as long as it is used with a consistent exercise program.

It contains a 100% protein blend, including whey concentrate and whey protein isolate. Each scoop contains 24 grams of protein, which is enough to kick start your lean muscle repair.

Other ingredients that can be found in GNC Pro Performance are BCAAs which are necessary for the growth, recovery, and maintenance of muscles.

Extra fuel is necessary whether you’re blasting through leg day or need additional support for an intense workout session. 

Luckily, the GNC whey protein powder helps you maintain adequate nitrogen levels in your diet. 

The GNC Pro Performance has also been tested to meet the industry’s high standards and contains no substances like added preservatives. It is also available in unflavored and other flavors such as natural chocolate.


  • Gluten-free
  • Fuels metabolism
  • Contains 100% whey protein supplements such as whey protein isolate and whey protein concentrate
  • Includes BCAAs
  • Increase muscle stores
  • Supports muscle growth, muscle recovery, and lean muscle mass
  • Maintains nitrogen levels
  • Available in other flavors


  • Unpleasant texture and mixability
  • Has a subpar taste

Check out more about the product at this link! 

4. GNC AMP Sustained Protein Blend – Chocolate Milkshake

Product Description

If you prefer whey protein shakes over tablets, you might want to try the GNC AMP Sustained Protein Blend

GNC AMP is a versatile protein powder suitable for non-training days and post-workout recovery. GNC AMP contains four protein sources, namely native micellar casein, native whey isolate, whey hydrolysate, and egg whites.

The GNC AMP protein shake contains 25g of 7-hour sustained protein release, which assists in ongoing muscle fuel, support, and recovery. 

Aside from its protein ingredients, the GNC AMP includes a rapid and sustained release of amino acids. Each serving of GNC AMP gives you 5 grams of BCAAs, which is an ample amount to kick start your muscle-building session.

Lastly, the GNC AMP protein blend includes gluten-free and soy-free formulas. 


  • GNC AMP delivers up to 7 hours of support
  • Assists in ongoing muscle fuel, support, and recovery
  • Includes rapid-release amino acids and sustained-release protein
  • Suitable for non-training days and post-workout recovery
  • Contains four protein sources


  • Unpleasant texture and taste

Interested? Check out this link! 

5. GNC Total Lean CLA

Product Description

Lastly, the GNC Total Lean CLA is ideal for those seeking a muscle-building supplement that supports lean muscle mass. CLA is a component that can’t be produced. However, it can be consumed by taking supplements or eating a well-balanced diet.

Its active ingredient is CLA, which is derived from safflower oil and contains 1000 mg per capsule. This component supports you in your body weight loss goals by suppressing your appetite. It also increases your process to lose fat, giving you more energy and preventing the future buildup of fat.

Scientifically, GNC Total Lean CLA improves lean muscle mass and human body composition. It also boosts your energy and metabolism without the use of stimulants. This gluten-free product is manufactured to assist you in taking control of your weight loss goals. 

According to the manufacturer, it is recommended that you take two capsules per day to achieve the best results. Lastly, GNC Total Lean CLA contains no added binders and preservatives.


  • Contains 180 capsules
  • Features 1000 mg of CLA per capsule
  • Supports lean muscle mass and body compositions
  • Boosts your energy and metabolism
  • No stimulants
  • Gluten-free
  • Allows you to take control of your weight loss
  • Suppresses appetite
  • Increases the process of burning fat
  • Prevents future buildup of fat


  • Might cause nausea
  • Might cause acne and hair loss

Check out this link for more info on the supplement! 

What to Look For in a GNC Supplement for Muscle Building?

Before rushing to the nearest drugstore, here are a few factors to consider first when buying the best GNC supplement for muscle building.

1. Budget

All supplements vary in price, but they can be costly since you’re looking for a GNC supplement for weight loss. It is valid to purchase a product that you can afford as long as it includes a list of good quality ingredients.

2. Testosterone

For men, testosterone is an important component to look for in a muscle-building product. This allows you to boost muscle growth, build muscle mass, and achieve delayed onset muscle soreness.

3. Protein

High-quality protein is an important ingredient to look for when buying a supplement to increase muscle stores rapidly. Protein is a naturally occurring substance found in foods like meat and fish. However, it can also be found in health supplements.

Some examples are casein protein, whey protein isolate, and whey protein concentrate. If you don’t prefer taking tablets or capsules, you can consider a soy protein drink for your post-workout recovery.

4. Strength and endurance

Your ideal supplement must provide you adequate muscle strength and endurance in completing weight lifting workouts. This will allow you to focus and enjoy your performance and journey to your fitness goals.

5. Natural ingredients

Aside from the essential components mentioned, we recommend you to look for a supplement that contains natural ingredients such as fruit and vegetable sources. As much as possible, avoid supplements that contain substances such as added preservatives.

6. Branched Chain Amino Acids

Branched-chain amino acids or BCAAs are another ingredients to consider when looking for a GNC Supplement. This excellent ingredient can help you in muscle gains and muscle protein synthesis. This also supports your muscles by providing essential electrolytes that were lost during intense workouts


Looking for the best supplement for muscle gain can be difficult and time-consuming. Finding the right product will not only help you with building muscle, but will also keep you healthy, lose fat, and achieve your fitness goals faster. Luckily, we’ve gathered five of the best GNC supplements for you to choose from. 

We highly recommend the GNC Mega Men Support Multivitamin, which supports men’s overall performance, the function of muscle, and health. It is specially manufactured for physically active men who desire more for their bodies.

If you liked this article, you might want to read our other articles at

Nathan Lloyd, MSc

I’m a personal trainer, based in Boulder, Colorado.
I service clients physically in the Boulder area, mainly in the ONE Boulder Fitness Gym, but am also available for online consulting and coaching.

If you’re interested in my personal coaching programs, please contact me via the contact page.