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Optimum Nutrition Gold Standard ‘Fit 40 Stack’ Review: Protein, Performance Booster, and Joint Health

Here’s a full review of Optimum Nutrition’s ‘Fit 40’ Supplements.

Matthew Magnante, ACE
We provide honest reviews based on a thorough, multi-point testing methodology . We do earn a commission if you purchase through our links, supporting our independent product assessments. View our disclosure for more details.

Optimum Nutrition is a leading nutritional supplement company with a hefty selection of various products and a good reputation at that.

And you’re probably familiar with their flagship Gold Standard 100% whey protein that has made its way into many households. But today we’re reviewing three products (protein, performance booster, joint health) from their recently released ‘Fit 40’ line which was formulated for active 40+ individuals. 

So without further ado, let’s dig in…

Gold Standard Fit 40 Stack
Gold Standard Fit 40 Stack

Gold Standard Fit 40 Muscle Recovery Protein Powder

I think we could all agree that protein is essential for building muscle and body tissue, in general, since this is its function in the human body. And sometimes we may not get enough through diet and this is where a good supplement can be very beneficial. Or maybe… we just like the convenience which supplementation offers.

Gold Standard Fit 40 Protein Powder
Gold Standard Fit 40 Protein Powder

Well, the Fit 40 ‘protein for muscle recovery’ from ON is truly a viable option for what it’s intended for. 

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Gold Standard Fit 40 Protein Powder

Gold Standard Fit 40 Protein Powder

Gold Standard Fit 40 Protein Powder

 Fit 40 Protein Powder delivers high-quality protein (ultra-filtered for exceptional purity & fast digestions). L-Leucine supports protein synthesis, muscle recovery, and muscle gain.

It contains 150 calories, 2g fat, 50mg (17%) cholesterol, 4% sodium, 4g (1%) carbs, 2% fiber, 2g sugar, and a much appreciated 30 grams of the muscle-building macronutrient… protein. 

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A serving also contains 15% calcium for bone and heart health, in addition to 4% iron (healthy blood cells), and 6% potassium (important electrolyte mineral for heart and muscle health).

The milk-based protein blend contains isolate (90% or more protein content), concentrate (less filtered whey but still a quality source), and hydrolyzed whey concentrate for better absorption.

Now, there are additional ingredients which user may choose to steer away from which include artificial flavoring (also includes natural flavoring) maltodextrin, sucralose, and soy.  

Fit 40 Protein Nutrition Facts
Fit 40 Protein Nutrition Facts

Maltodextrin is a food additive and carbohydrate source with a glycemic index of 130 (double that of table sugar) which means it can spike blood sugar relatively quickly.

Although, the amount contained in the product is very low so it shouldn’t be an issue for most people. 

Then you have sucralose which is a non-caloric artificial sweetener that is much sweeter than sugar although it doesn’t have a bitter aftertaste like many other sweeteners. 

But some people just don’t like how sweet it is and for some, it can cause some digestive discomfort.

Now, you might be thinking… what’s so great about this product for the active 40+ crowd? 

Well, if you’re familiar with the protein content in many similar products, you’ll notice that 30g of protein per serving is more than most protein supplements which typically contain 20-25 grams per serving. And while this won’t make a significant difference if your intake is sufficient for your goals, an extra 5 grams a couple times per day can’t hurt.

Fit 40 Protein Chocolate
Fit 40 Protein Chocolate

When you reach your forties and above, muscle retention is even more important. So, the formula also contains additional leucine which is the most important amino acid for stimulating protein synthesis which facilitates the muscle-building process. (1)

All-in-all, if you’re going to invest in a protein supplement, choosing one with extra protein and leucine in each serving isn’t a bad idea.

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Gold Standard Fit 40 Protein Powder

Gold Standard Fit 40 Protein Powder

Gold Standard Fit 40 Protein Powder

 Fit 40 Protein Powder delivers high-quality protein (ultra-filtered for exceptional purity & fast digestions). L-Leucine supports protein synthesis, muscle recovery, and muscle gain.

Gold Standard Fit 40 Training & Performance Booster

Performance-aiding supplements serve a specific purpose when it comes to higher-intensity and/or endurance type activities. It’ll give you more energy while increasing focus, therefore allowing you to train harder and longer.

Fit 40 Performance Booster
Fit 40 Training & Performance Booster

And depending on the additional ingredients, there’s no doubt you’ll experience real effects in performance.

Well, the Fit 40 training booster contains several different ingredients to support optimal performance in the 40+ age group without caffeine and only proven ingredients.

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Gold Standard Fit 40 PreWorkout

Gold Standard Fit 40 PreWorkout

Gold Standard Fit 40 PreWorkout

Fit 40 PreWorkout is a training and performance booster. HMB, Creatine Monohydrate and Beta-alanine provide support in muscle strength and rebuilding.

Now, besides having 100% vitamin D (immune system, heart, and bone health) and 37% calcium daily value, there aren’t many basic nutrients which is perfectly okay because it’s not intended to be a complete nutritional supplement.

With each serving, you get 3g of creatine monohydrate which is a long-studied and the most proven ergogenic aid that improves high-intensity exercise, supports strength, and helps to build muscle. (2)

It creates energy (ATP) in the muscle cells and also retains intracellular water to increase strength and potential muscle growth as a result. And to the surprise of many people interested in supplementation for hypertrophy effects, there’s evidence that shows elevated levels of muscle-building hormones (IGF-1) following creatine intake. (3, 4)

Fit 40 Pre Workout Label
Fit 40 Pre Workout Label

But creatine is completely safe for most individuals both short and long term. In fact, studies show there to be neuroprotective benefits and there are several potential therapeutic uses for it besides just performance and body composition. (5, 6, 7, 8)

So, if you want to maximize your performance then creatine is a good addition to your nutritional regime. Although results will vary between individuals. 

Then you have 3g of calcium HMB which is a metabolite of leucine that we discussed earlier and it’s helpful for post-exercise recovery and aiding leucine’s function.

CarnoSyn (beta-alanine) is another ingredient used in this formula which is a non-essential amino acid produced in the liver which combines with histidine to create a dipeptide called carnosine that is responsible for much of the performance-enhancing effects

Carnosine reduces lactic acid build-up in the muscles allowing for harder and longer muscle contractions and it also has disease-preventing properties which is good news, especially for the age group where this usually becomes more of a concern. (9

But beta-alanine has some effects on its own separate from carnosine and you probably recognize this compound as causing a ‘tingling’ effect or paraesthesia (nothing to be concerned about). 

Research shows beta-alanine to have performance benefits and it even reduces neuromuscular fatigue in older adults. One study even showed beta-alanine to increase total work done by 13% after 4 weeks in individuals who engaged in cycling, and then an additional +3.2% increase at 10 wks.

But, this was the case following an increase in carnosine. (10, 11)

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The pre-workout also contains a mushroom blend, plus 750mg arginine (nitrosigine) which synthesizes nitric oxide and opens blood vessels for more blood flow (pumps)!

It’s often used for cardiovascular conditions and even erectile dysfunction aside from being included in many performance supplements.

But studies also show arginine to have a positive effect on the immune system and an increase in time to exhaustion in male wrestlers although it’s not clear how this process occurs. (12, 13)

And to round out the main ingredient profile is 150mg elevATP (ancient peat, apple extract). 

Research shows that these ingredients may enhance performance adaptations like lower and total body strength which was determined after administering 150mg (ancient peat and apple extract) vs. a placebo to 25 healthy resistance-trained males. (14)

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Gold Standard Fit 40 PreWorkout

Gold Standard Fit 40 PreWorkout

Gold Standard Fit 40 PreWorkout

Fit 40 PreWorkout is a training and performance booster. HMB, Creatine Monohydrate and Beta-alanine provide support in muscle strength and rebuilding.

Therefore, exogenous ATP supplementation appears to have some benefits. 

Now as far as the additional ingredients, there is artificial flavoring and coloring (Red 40) in addition to gum bases which can cause stomach discomfort in some individuals. Sucralose and acesulfame potassium (artificial sweeteners) are also included which are oftentimes deal breakers for supplement users. 

Although, both are deemed safe by the FDA.

Gold Standard Fit 40 Joint Health Capsules

Joint health is of utmost importance regardless of age but the 40+ group is especially susceptible to stiffness, less flexibility, inflammation, pain, and deformity due to degeneration of cartilage and fluids over time. (15)

Gold Standard Fit 40 Joint Health
Gold Standard Fit 40 Joint Health

Joints are the area where two or more bones meet (cushion) which allow for flexible movement of the skeleton and inside these joints are cartilage and fluids with synovial membranes around the outside. 

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Gold Standard Fit 40 Collagen

Gold Standard Fit 40 Collagen

Gold Standard Fit 40 Collagen

 Fit 40 Active Joint Health combines UC-II Collagen, Turmeric, and Vitamin C to help support collagen synthesis and joint health. Easy to swallow.

So, if you can decelerate loss of function in your joints, then it’d be wise to look at your options. 

Let’s look at ON’s Fit 40 joint health supplement…

One serving contains 100% daily value of vitamin C which is important for immune system health, protein metabolism, and connective tissue. But it’s also important for the biosynthesis of collagen (and other neurotransmitters) which is also included in this formula, and it has antioxidant properties to protect the body against free-radical damage.

And for the main ingredients responsible for the joint health benefits… there’s 150mg cucumber extract, 100mg Hops extract, 50mg turmeric extract, 40mg UC-II chicken cartilage (contains 10mg total collagen), and 10mg Bioperine black pepper extract.

Fit 40 Joint Health Ingredients
Fit 40 Joint Health Ingredients

Cucumber is not only great for the skin but it contains vitamin C, lipids, protein, and minerals.

Hops extract is good for staving off swelling but it’s also commonly used for mood disorders.

Turmeric has shown to have anti-oxidant and anti-inflammatory for arthritis, anxiety, hyperlipidemia, and even metabolic syndrome. And it’s even beneficial for exercise recovery according to research. (16)

But it’s effects are most pronounced when combined with piperine which is also included in this formula (Bioperine).

In one study of 55 subjects who experienced joint pain during physical activity, 40mg of UC-II supplementation a day improved knee joint extension in healthy individuals, and it helped to prolong activities which would normally cause pain to arise. (17)

But it has been studied and used as an effective treatment for rheumatoid arthritis and osteoarthritis as well. (18)

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Gold Standard Fit 40 Collagen

Gold Standard Fit 40 Collagen

Gold Standard Fit 40 Collagen

 Fit 40 Active Joint Health combines UC-II Collagen, Turmeric, and Vitamin C to help support collagen synthesis and joint health. Easy to swallow.

And for the last ingredient on the list, Bioperine (piperine) is very effective for increasing the bioavailability of nutrients, and as we just mentioned it increases the effectiveness of turmeric.

So, we think it can be concluded that this formula is a powerhouse of benefits. 

Our Opinion Of All Three

We’ll start by saying that the active ingredients in all three supplements are clearly beneficial for active 40+ individuals.

There’s the protein with additional grams per serving in addition to extra leucine to ensure an optimal environment to support muscle protein synthesis.

Then you have the performance booster which contains ingredients which research shows do, in fact, have positive effects on physical performance, body composition, and overall health.

Lastly, the joint health supplement is formulated with several ingredients shown in studies to contain beneficial compounds that have antioxidant and anti-inflammatory properties in addition to collagen and Bioperine to improve bioavailability. 

Now, the above-mentioned ingredients are generally safe when used in recommended doses which should always be the case for nutritional supplements (although, it’s always).

However, there are additional ingredients used in formulas like artificial sweeteners, flavors, colors, and additives which are all deemed safe for consumption although there are different opinions on this.

But the amounts are likely nothing to worry about for most people unless you’re someone who prefers “all-natural” products which none of the products we reviewed are. 

Do We Recommend?

Although there’s certainly nothing groundbreaking here, each does have its benefits and will work as well as any top-notch options in its category. So, it really comes down to what you’re looking for overall. But, the Fit 40 line will definitely serve its purpose with realistic expectations.


If you have any questions about this article, please feel free to contact Matthew Magnante by leaving a comment below.

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Matthew Magnante, ACE
Matthew Magnante, ACE
Matthew is an ACE (American Council On Exercise) certified fitness professional who has had a passion for fitness since elementary school and continues to research and learn how to build muscle effectively through training and diet. He also loves to help others to achieve their fitness goals and spread the knowledge where needed. Matthew's other passions include learning about mindfulness, strolling through nature, traveling, and always working to improve overall.

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