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Optimize your joints for flexibility, comfort and long-range health*

  • Joint lubrication and shock absorption*
  • Support ligaments, tendons, cartilage*
  • Herbal relief for stiff, achy joints*
Upgrade Yourself®with Performance Lab® Flex

Stay limber and comfortable at work, leisure, athletics and all that you do.

Healthy joints support physical performance. But active lifestyles may lead to joint aches that limit your performance and long-range potential.

Performance Lab® Flex ultramodern joint nutrients are curated and combined for active joint demands.

Flex soothes and protects achy joints with easy-on-the-stomach botanicals AprèsFlex® Boswellia serrata and CurcuWIN® curcumin.

Flex also lubricates and nourishes joints with Mythocondro® chondroitin, NutriGenesis® strontium, OptiMSM® and corn glucosamine – all vegan-friendly upgrades over other joint products’ shellfish and animal ingredients.


Designed for Performance

  • Promotes faster, longer-lasting joint relief with patented botanical extracts*
  • Optimizes joint-lubricating synovial fluid for smooth, comfortable motion*
  • Supports flexible and resilient ligaments, tendons and connective tissues*
  • Maintains cushy, hydrated cartilage to help with joint shock absorption*

Healthy for Daily Use

  • Nourishes cartilage, connective tissues and bone to help maintain overall joint health*
  • Cutting-edge AprèsFlex®, CurcuWIN®, Mythocondro®, OptiMSM® and NutriGenesis®
  • Protects connective tissues from destructive free radicals and enzymes 5-LOX and MMP*
  • Clean vegan-friendly formula. Some other joint supplements have dubious animal origins
  • Natural joint relief that is easy on the stomach, unlike some harsh synthetics*
  • 100% natural prebiotic-infused NutriCaps® made from pullulan (fermented tapioca)


Supplement Facts

Peak Flexibility Performance Across All Lifestyles

Unlike typical joint supplements, Flex is a flexibility formula for all lifestyle-related joint concerns:

  • Strength training: Lifting can tweak shoulders and backs, limiting gym time and gains.
  • Endurance activities: Long-distance running and others impact knees, hips and ankles.
  • Tech usage: Texting, tapping and typing can strain connective tissues in fingers and wrists.
  • Professional activities: From desk jobs to manual labor, repetitive motions may strain joints.
  • Active 55+: Age-related joint and mobility problems can significantly impair quality of life.
Knee Structure

Performance Lab® Flex soothing botanicals and joint building blocks help you excel today, bounce back tomorrow and maintain healthy flexibility over time.

1. Soothing Botanicals for Natural Joint Comfort

AprèsFlex® Boswellia Serrata, 100 mg

Desert tree Boswellia Serrata produces a gum resin containing active boswellic acids, with AKBA (3-O-acetyl-11 keto-ß-boswellic acid) as the most effective for joint health. AKBA helps joints by:

  1. Modulating immune responses to help protect and soothe joints;
  2. Blocking 5-LOX, an enzyme that eats away at cartilage over time;
  3. Limiting matrix metalloproteinase (MMP) enzyme that weakens connective tissues.

Boswellia Serrata has been linked to improvements in joint aches, flexion and performance of daily activities in human clinical research.

ApresFlex® Boswellia Serrata

AKBA soothes joints and protects cartilage and connective tissues.

Performance Lab® Flex AprèsFlex® leverages advanced nutritional technology to achieve 52% greater absorption than plain Boswellia. It is also standardized to 20% AKBA for reliable joint benefits.

CurcuWIN® Curcumin, 250 mg

Ayurvedic root spice Turmeric gets its bright yellow color from plant pigments called curcuminoids. Curcumin is the primary curcuminoid suggested to help joint health and flexibility by:

  1. Fighting joint-destructive free radicals with potent antioxidant activity;
  2. Regulating COX-2 enzyme to soothe achy joints;
  3. Protecting cartilage cells from destructive matrix metalloproteinase (MMP) enzymes;
  4. Supporting synthesis of collagen and other structural joint proteins;
  5. Reducing advanced glycation end-products (AGEs) that stiffen connective tissues.

Curcumin has been linked to improvements in joint stiffness, comfort and overall functional performance in human clinical research.


Curcumin - Human trials suggest Curcumin enhances joint flexibility and comfort.

Performance Lab® Flex CurcuWIN® is an ultramodern nutritional innovation that makes curcumin 46X more absorbable. CurcuWIN® is also standardized to 20% curcuminoids in turmeric-identical ratios.

CurcuWIN® Chart

Performance Lab® Flex Advanced Botanical Stack
AprèsFlex® Boswellia Serrata + CurcuWIN® Curcumin

  • Extensively researched: Both have been used in herbalism for centuries; both have demonstrated joint benefits in multiple modern studies, including in combination.
  • Combination benefits: Work better together by targeting the same flexibility pathways with unique bioactivities that help individually and in tandem.
  • Safer, healthier and easier to take: Some synthetics for joint aches can upset the stomach and disrupt proteins that are needed to repair cartilage.

With AprèsFlex® Boswellia Serrata + CurcuWIN® Curcumin, Performance Lab® Flex supplies the two best forms of the two best joint-supportive botanicals known to science.

2. Maintenance Support for Healthy Joint Structure

Beyond botanical support, Flex supplies building blocks Glucosamine. Chondroitin and MSM – the most evidence-backed joint stack known to science – plus mineral Strontium to support joint function, strength and renewal over time:

Glucosamine Sulfate 2KCI (from corn), 500 mg

Glucosamine is an amino sugar naturally found in the tissues that surround, cushion and support the joints – including cartilage, ligaments, tendons and synovial fluids. Glucosamine supports:

  1. Building-block proteins that are used to form connective tissues;
  2. Chondrocyte cells within joints that repair and regenerate cartilage;
  3. Joint-lubricating synovial fluid for smooth, comfortable range of motion.

Performance Lab® Flex Glucosamine is vegan. Most glucosamine is sourced from shellfish. Flex instead supplies the research-backed Glucosamine Sulfate form sourced from a clean alternative: Corn.


Glucosamine Sulfate cushions, lubricates and supports strong joints.

Mythocondro® Chondroitin Sulfate, 100 mg

Chondroitin is a complex of large molecules that weave through the extracellular matrix of cartilage. Its strong negative charge attracts and holds water in cartilage like a sponge. Chondroitin helps joints by:

  1. Maintaining hydration for lubricated, shock-absorbing cartilage performance;
  2. Supporting healthy collagen production, a key building block of healthy joints;
  3. Promoting chondrocyte cells that regulate cartilage growth and repair.

Performance Lab® Flex Mythocondro® boosts chondroitin bioavailability by 43% for superior joint support at a lower dosage. Mythocondro® is also the only vegetarian chondroitin; other forms have animal origins including pork byproducts, shark cartilage and bovine connective tissue.

Mythocondro® Chondroitin Sulfate

Chondroitin Sulfate acts as a shock-absorber, supporting healthy growth and repair.

OptiMSM® Methylsulfonylmethane (MSM), 100 mg

Organic sulfur Methylsulfonylmethane (MSM) is a key structural nutrient needed to form and maintain collagen, glucosamine, chondroitin and other proteins that comprise cartilage and connective tissues.

Performance Lab® Flex OptiMSM® is the purest and only GRAS-designated MSM, made in the USA with a proprietary multi-stage distillation process that yields superior purity, quality and consistency.


MSM slows the breakdown of cartilage, protecting against bone-grinding wear and tear.

NutriGenesis® Strontium, 300 mcg

Strong bones support joint heath and flexibility. A calcium-like trace mineral, strontium migrates to the skeletal system where it is incorporated into bone matrix crystals. Here, strontium works by:

  1. Stimulating the production of osteoblasts (bone-building cells)
  2. Inhibiting the activity of osteoclasts (bone-breakdown cells)

Strontium’s dual activities may be ideal for joint health because they combine to help preserve existing bone integrity, especially the subchondral bone that forms a smooth, strong surface under cartilage.

Performance Lab® Flex NutriGenesis® Strontium is lab-grown on cultures to produce a clean and bioavailable elemental mineral supplement for superior bone strength support.

Nutrigenesis Icon

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Performance Lab® Flex

Ready to upgrade your flexibility? Take Performance Lab® Flex to soothe joint aches, maintain joint health and excel physically at everything you do.

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Who should take Performance Lab® Flex?

Performance Lab® Flex can be taken by anyone seeking a clean, advanced formula with premium research-backed nutrients for joint comfort, flexibility and skeletal strength. Bodybuilders, athletes and weekend warriors who are taking Performance Lab® SPORT supplements may need extra support for their musculoskeletal system, and benefit from taking Flex. It is equally suitable for active adults over the age of 55 seeking to nourish their joints and bones for long-range health while supporting quality of life and comfortable flexibility.

How do I take Performance Lab® Flex?

Take 2 capsules daily. For additional soothing joint support take 2 capsules immediately after physical activity. For best results use daily and consistently.

Is Performance Lab® Flex safe?

Like other Performance Lab® supplements, Flex is designed to be safe for long-term daily use. It uses minimum effective dosing along with premium, highly bioavailable ingredients to improve tolerability.

I am a senior. Can I take Performance Lab® Flex?

Flex is helpful for adults over age 55 because it soothes age-related joint aches with botanicals that are far easier on senior digestion than commonly used synthetic therapies. However, Performance Lab® Flex supplies only maintenance doses of glucosamine, chondroitin and MSM, which may be the most important nutrients for age-related joint problems.

What is NutriGenesis®?

NutriGenesis® is a Performance Lab® nutrition technology innovation: Vitamins, minerals and amino acids grown in live cultures at our state-of-the-art lab.

A true biological nutrient form, NutriGenesis® closely mirrors the molecular structure of food nutrients. NutriGenesis® nutrients offer significant advantages over standard nutrient forms.

Featured in several Performance Lab® formulas, NutriGenesis® vitamins, minerals and amino acids are bioengineered to be safe, active and highly effective for overall health and performance.

Why did Performance Lab® develop NutriGenesis®?

Vitamins, minerals and amino acids are the most important nutrients you need to build a strong foundation for health and performance.

Performance Lab® developed NutriGenesis® to have our own in-house vitamins, minerals and amino acids to use in our own nutritional supplements.

In producing NutriGenesis®, Performance Lab® can best maintain our industry-leading quality standards for cleanliness, purity, effectiveness and eco-friendliness, across all our ultramodern formulas.

How is NutriGenesis® different from other nutrient forms?

Not all vitamins, minerals and amino acids are the same. There are many nutrient forms, produced with a variety of processes. Some of the most popular nutrient forms available in supplements today include:

Whole Food Concentrates

Whole food vitamin and mineral supplements are sourced from fruits, vegetables, herbs and mushrooms. They include natural cofactors that make food nutrients so easy for the body to absorb and utilize. However, they do require extensive processing and may be made with GMOs, mass agriculture and dirty eco-destructive practices.

Isolated Chemical (USP) Nutrients

Isolated Chemical (USP) is the cheapest vitamin and mineral form found in the most basic multivitamin supplements. This synthetic form chemically alters vitamins and minerals, isolating them from their whole-food cofactors. As a result, Isolated Chemical (USP) nutrients are typically harder to absorb and less effective than whole food nutrients.

Chelated Minerals

In this process, a mineral nutrient (such as iron, calcium, zinc) is bound with a chelator: An organic molecule (often an amino acid) that is large enough to enrobe the mineral. By surrounding the mineral, the chelator protects it against degradation. Chelated nutrients are highly stable and may improve nutrient uptake and utilization.

NutriGenesis® is different from traditional nutrient forms: Bioengineered to be better.

NutriGenesis® are cultured nutrients that replicate the creation of vitamins, minerals and aminos in nature.

NutriGenesis® is based on the work of Nobel Prize-winning physiologist Albert Szent Gyorgy, who theorized that nutrients presented in their naturally grown forms supply cofactors that make them more bioavailable, biologically active and effective than nutrients that are isolated.

In the NutriGenesis® process, single-cell organisms (Lactobacillus probiotics and brewer’s yeast) are seeded with micronutrients in a hydroponic growth medium.

The live single-cell organisms “eat” the micronutrients, divide and thrive. As the cultures grow, they produce fresh new NutriGenesis® vitamins, minerals and aminos within a matrix of natural cofactors. This familiar structure is more easily absorbed and utilized by the body.

More on the NutriGenesis® Process

NutriGenesis® advantages over other forms:

NutriGenesis® is essentially food nutrition. Mirroring food nutrients molecule-by-molecule, our vitamins, minerals and aminos are presented in pure elemental form. Maximum nutrition: Nothing more, nothing less.

Enhanced effectiveness. Because NutriGenesis® nutrients are in food-matrix form, they are recognized by the body as nature-identical -- maximizing nutrient uptake, bioavailability and beneficial activity.

Patented and researched. The patented process behind NutriGenesis® has been shown in research to enhance nutrient absorption and retention (when compared to chemical isolates).

Cleaner and safer. NutriGenesis® is produced in a sterile, tightly controlled lab setting. NutriGenesis® is minimally processed, requiring no pesticides, herbicides or other synthetics associated with some other whole-food nutrients.

Better for the planet: The NutriGenesis® process is clean and efficient, with little carbon footprint or environmental impact – especially when compared to factory farming for phytonutrients and strip mining for minerals.

Which formulas feature NutriGenesis® nutrients?

It all begins with NutriGenesis® Multi for Men and Multi for Women: Performance Lab®’s multivitamin starting point for human performance optimization.

NutriGenesis® vitamins, minerals and amino acids are also found in Performance Lab® formulas Stim, Flex, BCAA, Pre, Post and Maintain.

Beyond Performance Lab®, NutriGenesis® B-Vitamins are found in Mind Lab Pro®: the Universal Nootropic™.

30-Day Performance Promise

Your first order of any Performance Lab® product is covered by our 30-day performance promise.

Put Performance Lab® Flex to the test for a full 30 days and if you don’t see results, we’ll refund your money. No questions asked.

Simply get in touch with a member of our Customer Care team to arrange the return of the empty bottle, and any unused bottles.

The Performance Lab® Performance Promise covers one box of any of our products, up to a maximum of three products per order.

Flex stacks well with…

Flex + NutriGenesis® Multi for Men

NutriGenesis® Multi augments Flex with Vitamin D3, Calcium, Magnesium and Vitamin K for bone strength; plus Vitamin C for collagen and connective tissues.

Take Flex + NutriGenesis® Multi for far-reaching flexibility support ranging from joint basics to advanced forms of today’s greatest joint-soothing botanicals and joint-building raw materials.

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NutriGenesis® Multi for Men

Flex + NutriGenesis® Multi for Women

NutriGenesis® Multi augments Flex with Vitamin D3, Calcium, Magnesium and Vitamin K for bone strength; plus Vitamin C for collagen and connective tissues.

Take Flex + NutriGenesis® Multi for far-reaching flexibility support ranging from joint basics to advanced forms of today’s greatest joint-soothing botanicals and joint-building raw materials.

Learn More
NutriGenesis® Multi for Women

Flex + Sleep

Sleep CherryPURE® soothes sleep-disruptive aches, while its Magnesium relaxes muscles and nourishes bone – stacking effectively with Flex’s joint-soothing botanicals and bone mineral Strontium.

Take Sleep + Flex to extend joint-regenerative sleep while nourishing cartilage, connective tissues and bone for healthy long-range flexibility.

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Flex + Post

SPORT Post nourishes muscle repair and reduces soreness after exercise.

Flex offers similar benefits for joints – soothing post-workout aches while nourishing for optimal joint repair, comfort and function.

Take Flex + SPORT Post after exercise to help muscles and connective tissues return to form faster, healthier and stronger.

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Flex + Protein

Beyond nourishing muscle, SPORT Protein helps form collagen and elastin: connective tissue building-blocks that support healthy tendons and ligaments.

Add SPORT Protein to Flex for extra musculoskeletal support and greater physical performance potential.

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The research and studies behind Performance Lab® Flex.

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Boswellia Serrata

Ammon HP. Salai Guggal – Boswellia serrata: from a herbal medicine to a non-redox inhibitor of leukotriene biosynthesis. Eur J Med Res. 5-24-1996;1(8):369-70.
Ernst E. Frankincense: systematic review. BMJ. 2008 Dec 17;337:a2813.
Singh S, Khajuria A, et al. Boswellic acids and glucosamine show synergistic effect in preclinical anti-inflammatory study in rats. Bioorg Med Chem Lett. 2007 Jul 1;17(13):3706-11.
Sharma ML, Bani S, et al. Anti-arthritic activity of boswellic acids in bovine serum albumin (BSA)-induced arthritis. Int J Immunopharmacol. 1989;11(6):647-52.
Gupta, P. K. et al. Clinical Evaluation of Boswellia Serrata (Shallaki) Resin in the Management of Sandhivata (osteoarthritis). Ayu 32.4 (2011): 478–482. PMC. Web. 14 Sept. 2018.


Chainani-Wu N. Safety and anti-inflammatory activity of curcumin: a component of tumeric (Curcuma longa). J Altern Complement Med. 2003 Feb;9(1):161-8.
Funk JL, Frye JB, et al. Efficacy and mechanism of action of turmeric supplements in the treatment of experimental arthritis. Arthritis Rheum. 2006 Nov;54(11):3452-64.
Funk JL, Frye JB, et al. Anti-arthritic effects and toxicity of the essential oils of turmeric (Curcuma longa L.). J Agric Food Chem. 2010 Jan 27;58(2):842-9.
Kuptniratsaikul V, Thanakhumtorn S, et al. Efficacy and safety of Curcuma domestica extracts in patients with knee osteoarthritis. J Altern Complement Med. 2009 Aug;15(8):891-7.
Goel A, Kunnumakkara AB, Aggarwal BB. Curcumin as “curecumin”: from kitchen to clinic. Biochem Pharmacol 2008;75:787-809. 17. Abe Y, Hashimoto S, Horie T.
Curcumin inhibition of inflammatory cytokine production by human peripheral blood monocytes and alveolar macrophages. Pharmacol Res 1999;39:41-47.
Surh YJ, Chun KS, Cha HH, et al. Molecular mechanisms underlying chemopreventive activities of anti-inflammatory phytochemicals: down-regulation of COX-2 and iNOS through suppression of NFkappa B activation. Mutat Res 2001;480-481:243-268.
Jobin C, Bradham CA, Russo MP, et al. Curcumin blocks cytokine-mediated NF-kappa B activation and proinflammatory gene expression by inhibiting inhibitory factor I-kapp.
Deodhar SD, Sethi R, Srimal RC. Preliminary study on antirheumatic activity of curcumin (diferuloyl methane). Indian J Med Res 1980;71:632-634.
Goel A, Kunnumakkara AB, Aggarwal BB. Curcumin as “curecumin”: from kitchen to clinic. Biochem Pharmacol 2008;75:787-809.
Abe Y, Hashimoto S, Horie T. Curcumin inhibition of inflammatory cytokine production by human peripheral blood monocytes and alveolar macrophages. Pharmacol Res 1999;39:41-47.
Surh YJ, Chun KS, Cha HH, et al. Molecular mechanisms underlying chemopreventive activities of anti-inflammatory phytochemicals: down-regulation of COX-2 and iNOS through suppression of NFkappa B activation. Mutat Res 2001;480-481:243-268.


Lin YC, Yiang YC, et al. Chondroprotective effects of glucosamine involving the p38 MAPK and Akt signaling pathways. Rheumatol Int. 2008 Aug;28(10):1009-16.
Pearson and Lindinge. Critical review of research evaluating glucosamine-based nutraceuticals for treatment of joint pain and degenerative joint disease in horses. Proceedings of the 4th European Equine Nutrition & Health Congress; 2008 Apr.


Allen DO, Ahmed B, Naseer K. Relationships between cyclic AMP levels and lipolysis in fat cells after isoproterenol and forskolin stimulation. J Pharmacol Exp Ther. 1986 Aug;238(2):659-64.
Kavila C, et al. Coleus forskohlii: A comprehensive review on morphology, phytochemistry and pharmacological aspects. Journal of Medicinal Plants Research, Vol. 4(4) pp. 278-285, 18 February, 2010
Barnhill JG, Fye CL, et al. Chondroitin product selection for the glucosamine/chondroitin arthritis intervention trial. J Am Pharm Assoc (2003). 2006 Jan-Feb;46(1):14-24.
Singh JA, Noorbaloochi S, et al. Chondroitin for osteoarthritis. Cochrane Database Syst Rev. 2015 Jan;1:CD005614.
Uebelhart D, Thonar EJ, et al. Effects of oral chondroitin sulfate on the progression of knee osteoarthritis: a pilot study. Osteoarthritis Cartilage. 1998 May;6 Suppl A:39-46.


Kim LS, et al. (2006) Efficacy of methylsulfonylmethane (MSM) in osteoarthritis pain of the knee: a pilot clinical trial. OsteoArthritis and Cartilage; 14, 286e294.
Barmaki S, Bohlooli S, et al. Effect of methylsulfonylmethane supplementation on exercise – Induced muscle damage and total antioxidant capacity. J Sports Med Phys Fitness. 2012 Apr;52(2):170-4.
Notarnicola A, Maccagnano G, et al. Methylsulfonylmethane and boswellic acids versus glucosamine sulfate in the treatment of knee arthritis: Randomized trial. Int J Immunopathol Pharmacol. 2016 Mar;29(1):140-6.
Kim LS, Axelrod LJ, et al. Efficacy of methylsulfonylmethane (MSM) in osteoarthritis pain of the knee: a pilot clinical trial. Osteoarthritis Cartilage. 2006;14:286-94.
Notarnicola A, Tafuri S, et al. The “MESACA” study: methylsulfonylmethane and boswellic acids in the treatment of gonarthrosis. Adv Ther. 2011 Oct;28(10):894-906
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* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.