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Flexibility enhancer plus joint relief and renewal*

Upgrade Yourself®

Soothe + strengthen joints for peak physicality and long-range flexibility

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

Performance Lab® Flex helps with ultramodern joint nutrients, combined for active joint demands, and delivered in the cleanest, healthiest flexibility formula ever developed.

Flex soothes and protects achy joints with AprèsFlex® Boswellia Serrata and CurcuWIN® curcumin – easy-to-digest botanicals for joint relief without the stomach concerns linked to some synthetics.

Flex also helps joint lubrication, structure and strength with Mythocondro® chondroitin, NutriGenesis® strontium, OptiMSM® and corn glucosamine – all clean, vegan-friendly upgrades over basic joint supplements’ shellfish and animal ingredients.

Take Performance Lab® Flex for soothing joint comfort and peak flexibility performance across work, leisure, athletics and everything you do.

Take Performance Lab® Flex over time to nourish connective tissues with building block nutrients that help contribute to long-range joint health.


Designed for Performance

Promotes faster, longer-lasting joint relief with patented botanical extracts*

Optimises 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, connectives tissues and bone to help maintain overall joint health*

Protects connective tissues from destructive free radicals and enzymes 5-LOX and MMP*

Natural joint relief that is easy on the stomach, unlike some harsh synthetics*

Cutting-edge AprèsFlex®, CurcuWIN®, Mythocondro®, OptiMSM® and NutriGenesis®

Clean vegan formula. Some other joint supplements often have dubious animal origins

100% natural prebiotic-infused NutriCaps® made from pullulan (fermented tapioca)

100% Plant-Based
Synthetic Additive
Banned Substance

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.

Designed for performance, Flex helps keep you moving by targeting several key pathways for joint health and flexibility:

Knee Structure

Flex helps protect connective tissues from destructive enzymes and free radicals.

Flex modulates immune responses to further protect and soothe connective tissues.

Flex supports synthesis of synovial fluid that lubricates joints for smooth flexibility.

Flex nourishes ligaments and tendons for limber function and healthy repair.

Shock Absorption
Flex helps regenerate and hydrate cartilage, keeping it thick, cushy and healthy.

Bone Strength
Flex supports bone mineral density to help maintain joint end integrity.

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


Supplement Facts
Other Ingredients

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

3-0-acetyle-11 keto-boswellic acid - AKBA soothes joints and protects against cartillage and connective tissue damage.

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

CurcuWIN® Curcumin, 250 mg

Ayurvedic root spice Turmeric gets its bright yellow colour 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;
  1. Supporting synthesis of collagen and other structural joint proteins;
  2. 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.

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.


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

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

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 - 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 - 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.


Methylsulfonylmethane - Methylsulfonylmethane 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.

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

Take Performance Lab® Flex to soothe joint aches, bounce back faster and maintain healthy flexibility over time.

Upgrade Yourself®

Performance Lab® Flex helps joints and connective tissues to perform their best in motion and recover comfortably at rest. Upgrade your flexibility and excel physically at everything you do.


Recommended Add-Ons

Whole-Food Multi

Flex + Whole-Food Multi

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.


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. .


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.


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.


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.


The research and studies behind Performance Lab® Flex.

Learn More

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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