Performance Lab Flex Review (Updated in 2022)

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Did you come across Performance Lab Flex but you’re not sure whether its advertised effects are real? 

The brand, Performance Lab, is known for creating premium, yet highly effective supplements. However, one cannot always take their word for granted and simply accept any and every formulation without doing some proper digging. 

As an official skeptic, I’ll give you an overview of the supplement and I’ll also go through its different ingredients (and existing scientific evidence) to understand whether it’s actually effective for joint health. 

Overview of Performance Lab Flex

According to Performance Lab, Flex is a formula designed to relieve people with stiff, achy joints— including those who wish to continue exercising but find it difficult whilst experiencing joint pain. 

It contains ingredients such as MSM, Boswellia Serrata, Curcumin, Glucosamine, and Chondroitin, delivered in capsule form that one must take over a certain period to experience its effects.

Some of these ingredients are used in therapy to help with joint pain and stiffness, and other symptoms associated with osteoarthritis.

What Performance Lab has attempted to do was combine ingredients with different levels of efficacy to create a formula capable of tackling inflammatory reactions. 

However, that does not mean each ingredient is effective on its own as an anti-inflammatory, therefore I believe it’s important to go over each ingredient and determine how effective it is, and why it might play a role in this formula. 

What Are The Ingredients In Performance Lab Flex?

There is a level of scientific efficacy for the ingredients used in the Performance Lab Flex, in fact, some of its ingredients can also be found in other joint supplements sold in pharmacies. 

The ingredients in Performance Lab Flex are the following:

  • CurcuWIN® Turmeric (Curcuma Longa)(root) (20% Curcuminoids)
  • AprèsFlex® Boswellia Serrata (gum resin)(20% 3-0-acetyl-11-keto-β-boswellic acid [AKBA])
  • Glucosamine Sulfate 2KCL (from corn)
  • Mythocondro® (Chondroitin Sulfate)
  • OptiMSM® (Methylsulfonylmethane [MSM])

Despite the long scientific names, the base ingredients/compounds are pretty simple to pronounce.

Curcumin (Turmeric)

Curcumin is a yellow pigment found in turmeric — a plant from the ginger family that is best known for being used as a spice in curry. 

It is a polyphenol with anti-inflammatory properties and the ability to increase the number of antioxidants the body is capable of producing. 

Curcumin and the curcuminoids found in turmeric are the properties that scientists extract to produce supplements that have a much higher potency than turmeric. 


However, curcumin on its own isn’t effective, particularly because it’s poorly absorbed during digestion, so it’s necessary to have ingredients that support its absorption, namely black pepper extract or lipids. 

Curcumin supplementation has been shown to reliably reduce markers of inflammation and increase the levels of endogenous antioxidants in the body.

A 6-month long double-blind placebo-controlled study shows that curcumin dosed at 1,000mg MERIVA (curcumin combined with soy lecithin) taken in two divided dosages of 500mg, was safe and effective over a period of 8 months in alleviating clinical and biochemical symptoms of osteoarthritis in a population of middle-aged persons with osteoarthritis. 1

The Flex supplement by Performance Lab does not contain MERIVA, but it does contain BCM-95, which is basically a combination of curcumin and essential oils.

My issue with Flex is that it only contains 250mg of curcumin per serving, which is significantly lower than the amount used in scientific studies that have shown promising results. 

However, this formula is a cocktail with different ingredients, so it might be different. 

Boswellia Serrata

Boswellia Serrata is an Ayurvedic herb also classified as a phytopharmaceutical that appears to be quite anti-inflammatory, thus helpful against conditions such as osteoarthritis.

It is basically a gum resin extracted from a tree that is sometimes used as an aromatic or as medicine. 

The acids present in Boswellia Serrata have arisen as a novel inhibitor of a pro-inflammatory enzyme called 5-Lipoxygenase and may possess other anti-inflammatory effects. 

boswellia serrata

These inflammatory effects have been investigated for their effects in OA (osteoarthritis), and some evidence suggests that oral supplementation of Boswellia can suppress pain associated with OA and that these effects can occur in a few weeks. 

A double-blind, random placebo study was able to demonstrate that 100mg or 250mg 5-Loxin was able to confer benefits of joint pain relief in persons with osteoarthritis. 2

However, it’s also important to mention that even though these studies are well-conducted, they are funded by the producers of the tested Boswellia supplements, which is more often worse than good. 


Glucosamine is typically derived from shellfish, but the one used by Performance Lab is vegan-friendly because it’s derived from corn. It’s called Glucosamine Sulfate 2KCL.


Some studies suggest that glucosamine is capable of reducing the rate of collagen (joint tissue) degradation and symptoms of osteoarthritis. 

It is often compared to acetaminophen, the drug of reference used in the treatment of OA, but in terms of potency, it doesn’t appear to be as reliable. 

Studies on athletes supplementing with glucosamine are limited, but preliminary evidence suggests that doses as high as 3000mg can slow joint degradation. 3

Unfortunately, Performance Lab Flex does not contain 3000mg of glucosamine, so its impact and ability to slow joint degradation are inconclusive, to say the least. 

Chondroitin Sulfate

Chondroitin is a supplement that is frequently paired with Glucosamine as a means to help with joint pain and stiffness, as well as other symptoms associated with OA. 


Meta-analyses (which are basically studies to evaluate the quality of other studies) discovered that most studies emphasizing the benefits of chondroitin were poorly designed or subject to chance statistical error (typically due to small sample sizes). 4

More importantly, studies with larger sample sizes (thus, more reliable) show that both chondroitin and glucosamine supplementation do not have any benefits. 

It’s true that there are many people claiming that chondroitin combined with glucosamine is beneficial for joint pain and stiffness, however, the current body of evidence suggests otherwise. 

Methylsulfonylmethane [MSM]

Methylsulfonylmethane (or in short, MSM) is a small DMSO-related sulfur-containing molecule used for its antioxidative and anti-inflammatory properties. 


Like Glucosamine, it holds potential for joint health, however, there is no sufficient evidence.

Some studies show that taking 3000mg of MSM on a daily basis can reduce symptoms of osteoarthritis and confer some antioxidant protection to the body, however, this supplement only contains about 100mg per serving, so its effects should be reduced, or non-existent. 

Is Performance Lab Flex Effectiveness?

Performance Lab is a highly reputable brand in the nutritional/supplement space, and they usually create formulas with incredible benefits, mostly because they use scientifically-backed ingredients. 

Flex is advertised as a joint supplement, but one has to question its effectiveness.

Unfortunately, Flex contains a few ingredients that are dubious, and there isn’t sufficient evidence to show that they’re highly effective when it comes to joint health. 

For example, ingredients like Glucosamine and Chondroitin do not seem to have benefits in larger studies (studies with a larger pool of subjects). Smaller studies show some results, but they’re not properly conducted due to small sample sizes, and in some cases, they are funded by the actual supplement companies. 

This does not mean that Flex is a bad supplement in isolation— it just means that certain categories of supplements like joint supplements, often have ingredients that don’t have compelling scientific evidence. 

This being said, Flex contains ingredients such as Curcumin and Boswellia Serrata that have a decent amount of scientific evidence, and do offer promising results in terms of joint health.

My only issue is that Flex contains these ingredients in small doses, which often means that it might have a reduced or non-existent effect. 

Frequently Asked Questions

How Should You Take Performance Lab Flex?

The brand states that you should take two capsules of Performance Lab Flex per day.

How Much Does Performance Lab Flex Cost?

Performance Lab Flex is a bit more expensive than other joint supplements. One box with 30 servings costs about $62.10, which is equivalent to $2.10 per serving.

However, you can reduce the cost per serving by buying the product in bulk— for instance, if you purchase three boxes, you can reduce the cost per serving to $1.73. 

Where Is Performance Lab Flex Made?

Performance Lab Flex is actually made in the United States, hence why it’s more expensive than other supplements, as its production does not involve cheap labor.

Does Performance Lab Flex Have Side Effects?

Performance Lab Flex seems to be generally safe for adults, however, side effects such as mild skin irritation are a possibility. 

I’ve researched studies associated with each ingredient, and there are no studies demonstrating that high doses (1000mg +) are unsafe. 

However, I would still be careful if you’re pregnant or have serious health conditions. 

Is Performance Lab Flex Vegan-Friendly?

Yes, Performance Lab Flex is completely suitable for vegans.

The only ingredient that was dubious was Glucosamine (because it’s usually derived from shellfish), but the one used by Performance Lab was extracted from corn, which is vegan. 

Does Performance Lab Have A Refund Policy?

It’s possible to return Performance Lab Flex within 30 days of your first purchase. In other words, if you test the product for 30 days and don’t see any results, they’ll refund you the money. 

Is Performance Lab Flex Worth It?

Personally, I wouldn’t purchase Performance Lab Flex — mainly because I haven’t found sufficient evidence showing that it’s actually effective for joint issues.

A lot of the ingredients are not properly researched even though they make big claims, and that is why I’m very skeptical in regards to supplements of this kind.

Many joint supplements, unfortunately, have ingredients that don’t provide any benefits or are either delivered in less than optimal doses, which means they don’t produce any effect. 

If you want a joint supplement that is actually effective because it contains ingredients that are effective and available in the right doses, my suggestion would be for you to look at curcumin/turmeric supplements, as that is one ingredient that seems to have an actual effect on joint pain. 

A second suggestion would be for you to avoid foods that are highly inflammatory (refined foods with high sugar content, red meats, among others), as those are bound to leave you in a worse state. 

Lastly, the best course of action is to visit a specialized doctor such as a rheumatologist before you decide to take any supplement or medicine — and this is pretty much the best advice I can offer you. 

Editor’s note: The content on this website is meant to be informative in nature, but it should not be taken as medical advice. The content of our articles is not intended for use as diagnosis, prevention, and/or treatment of health problems. It’s always best to speak with your doctor or a certified medical professional before making any changes to your lifestyle, diet, or exercise routine, or trying a new supplement.

Scientific references:

1 – Belcaro G, Cesarone MR, Dugall M, Pellegrini L, Ledda A, Grossi MG, Togni S, Appendino G. Efficacy and safety of Meriva®, a curcumin-phosphatidylcholine complex, during extended administration in osteoarthritis patients. Altern Med Rev. 2010 Dec;15(4):337-44. PMID: 21194249.

2 – Sengupta K, Alluri KV, Satish AR, Mishra S, Golakoti T, Sarma KV, Dey D, Raychaudhuri SP. A double blind, randomized, placebo-controlled study of the efficacy and safety of 5-Loxin for treatment of osteoarthritis of the knee. Arthritis Res Ther. 2008;10(4):R85. doi: 10.1186/ar2461. Epub 2008 Jul 30. PMID: 18667054; PMCID: PMC2575633.

3 – Ostojic SM, Arsic M, Prodanovic S, Vukovic J, Zlatanovic M. Glucosamine administration in athletes: effects on recovery of acute knee injury. Res Sports Med. 2007 Apr-Jun;15(2):113-24. doi: 10.1080/15438620701405248. PMID: 17578751.

4 – Reichenbach S, Sterchi R, Scherer M, Trelle S, Bürgi E, Bürgi U, Dieppe PA, Jüni P. Meta-analysis: chondroitin for osteoarthritis of the knee or hip. Ann Intern Med. 2007 Apr 17;146(8):580-90. doi: 10.7326/0003-4819-146-8-200704170-00009. PMID: 17438317.

Hey there! My name is Alex and I've been vegan for over five years! I've set up this blog because I'm passionate about veganism and living a more spiritually fulfilling life where I'm more in tune with nature. Hopefully, I can use Vegan Foundry as a channel to help you out on your own journey!