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Xendurance
Clean Energy, without the Crash.
60-Day Money Back Guarantee
60-Day Money Back Guarantee
Endorsed by:
Proven In
12 Clinical Studies
Recover Faster
Fights free radical damage & supports crucial cellular functions
Stamina Increase
Push your limits to go the distance, fight fatigue and set PRs
Increase Power
Increase power output by 10-25% with a similar heart rate
Deeper Breaths
Increase VO2 Max & Aerobic Threshold. Perform better for longer
Deeper Breaths
Increase VO2 Max & Aerobic Threshold. Perform better for longer.
Reduce Lactic Acid
Extreme Endurance reduces lactic build up after intense workouts
Age Slower
Promotes anti-aging by reducing damaging oxidative stress
Journal of Athletic Achievement
ENA Conference, Vienna Austria
Journal of Athletic Achievement
ENA Conference, Vienna Austria
Lactic Acid Decreases by 26% In 7 Days
Muscle Damage (CK Levels) Decreases by 6x In 7 Days
V02 Max Increases by 15% In 8 Weeks
Trusted by
WORLD CLASS ATHLETES
Slide 1 of 6Why You’ll Love It
Break Through Limits – Clinically proven to reduce lactic acid by 26%, helping you push through fatigue.
Boost Stamina & Endurance – Supports oxygen efficiency and aerobic capacity, so you can go further without burning out.
Scientifically Backed Formula – Developed with 12+ clinical studies, NSF Certified for Sport® and trusted by elite athletes.
Fight Oxidative Stress – Lowers oxidative stress by 39%, protecting your muscles from breakdown and improving long-term performance.
Description
Clinically Proven
Feel confident knowing Extreme Endurance meets the standards of all major professional, collegiate, and Olympic organizations worldwide. This all-natural electrolyte mineral supplement contains no banned ingredients and is thoroughly tested to ensure it’s free of prohibited substances.
Since 2008, elite athletes have trusted Extreme Endurance for top-tier performance. Now, cutting-edge research proves its benefits extend beyond the pros—anyone can thrive. It helps optimize body pH, bolsters cellular health, and combats free radical damage effectively.*
Clinical Studies:
Key Benefits
The Benefits of Daily Use:
26% Reduction of Lactic Acid -> Less Muscle Soreness / Improves Performance*
39% Reduction of Oxidative Stress -> Fights Free Radical Damage*
6X Reduction of Creatine Kinase (CK) -> Faster Muscle Recovery Time*
Increase in Aerobic Threshold -> Last Longer, Go Harder*
Start feeling the benefits within 72 hours*
Certified by Informed Sport*
Clinically Proven
Backed by 12 unique clinical studies (two of which are published, Gold Standard, double-blind and placebo-controlled).
Extreme Endurance is arguably the most researched and proven sports supplement in the world.
Natural & Tested For Banned Substances
Formulated with 100% natural ingredients for ANYONE of any fitness level.
What's Inside
Feel confident knowing Extreme Endurance meets the standards of all major professional, collegiate, and Olympic organizations worldwide. This all-natural electrolyte mineral supplement contains no banned ingredients and is thoroughly tested to ensure it’s free of prohibited substances.
We recommend avoiding extra high-dose magnesium supplements while using Extreme Endurance. The daily dose of 6 tablets already provides plenty of magnesium, and too much could reduce the supplement’s benefits. A standalone magnesium supplement of 300 mg or more is considered high-dose when taken with Extreme Endurance.*
Calcium Carbonate
Supports muscle, bone, and heart function.
Papain
Papaya enzyme that reduces inflammation and muscle soreness after exercise.
Magnesium
Supports muscle function, relaxation, energy production, and reduces fatigue.
Potassium
Prevents cramps, balances electrolytes, and supports recovery after sweating.
Catechins
Fights oxidative stress, protects muscle cells, and aids recovery.
Chromium / Selenium
Trace minerals supporting metabolism, growth, and recovery.
Usage
For maximum benefits, it's essential to use Extreme Endurance daily, much like a multivitamin. Research shows that the longer you take it, the greater the results, so make a commitment to consistent daily use—we've even had athletes relying on it for over 14 years without interruption.To achieve optimal results, follow these simple guidelines:
Morning: Swallow 3 tablets of Extreme Endurance with or without food.
Evening: Swallow 3 tablets of Extreme Endurance with or without food.
We recommend avoiding stand-alone magnesium supplements while using Extreme Endurance, as adding 300 mg or more isn't advised. You'll already receive an ample daily dose of magnesium from the 6 tablets.
Extreme Endurance4.71 Stars
2544 Reviews
In a clinical study 93.5% athletes perform better
Default Title
1 Pouch
16 sticks
2 Pouch
32 sticks
3 Pouch
48 sticks
Choose an option:
BUY ONCE FOR $59.95 + $6.95 SHIPPING
4.76/5
Money Back
GuaranteeSame Day
ShippingFor optimal results, maintain consistent use for 3-6+ months
Why You’ll Love It
Break Through Limits – Clinically proven to reduce lactic acid by 26%, helping you push through fatigue.
Boost Stamina & Endurance – Supports oxygen efficiency and aerobic capacity, so you can go further without burning out.
Scientifically Backed Formula – Developed with 12+ clinical studies, NSF Certified for Sport® and trusted by elite athletes.
Fight Oxidative Stress – Lowers oxidative stress by 39%, protecting your muscles from breakdown and improving long-term performance.
Description
Clinically Proven
Feel confident knowing Extreme Endurance meets the standards of all major professional, collegiate, and Olympic organizations worldwide. This all-natural electrolyte mineral supplement contains no banned ingredients and is thoroughly tested to ensure it’s free of prohibited substances.
Since 2008, elite athletes have trusted Extreme Endurance for top-tier performance. Now, cutting-edge research proves its benefits extend beyond the pros—anyone can thrive. It helps optimize body pH, bolsters cellular health, and combats free radical damage effectively.*
Clinical Studies:
Key Benefits
The Benefits of Daily Use:
26% Reduction of Lactic Acid -> Less Muscle Soreness / Improves Performance*
39% Reduction of Oxidative Stress -> Fights Free Radical Damage*
6X Reduction of Creatine Kinase (CK) -> Faster Muscle Recovery Time*
Increase in Aerobic Threshold -> Last Longer, Go Harder*
Start feeling the benefits within 72 hours*
Certified by Informed Sport*
Clinically Proven
Backed by 12 unique clinical studies (two of which are published, Gold Standard, double-blind and placebo-controlled).
Extreme Endurance is arguably the most researched and proven sports supplement in the world.
Natural & Tested For Banned Substances
Formulated with 100% natural ingredients for ANYONE of any fitness level.
What's Inside
Feel confident knowing Extreme Endurance meets the standards of all major professional, collegiate, and Olympic organizations worldwide. This all-natural electrolyte mineral supplement contains no banned ingredients and is thoroughly tested to ensure it’s free of prohibited substances.
We recommend avoiding extra high-dose magnesium supplements while using Extreme Endurance. The daily dose of 6 tablets already provides plenty of magnesium, and too much could reduce the supplement’s benefits. A standalone magnesium supplement of 300 mg or more is considered high-dose when taken with Extreme Endurance.*
Calcium Carbonate
Supports muscle, bone, and heart function.
Papain
Papaya enzyme that reduces inflammation and muscle soreness after exercise.
Magnesium
Supports muscle function, relaxation, energy production, and reduces fatigue.
Potassium
Prevents cramps, balances electrolytes, and supports recovery after sweating.
Catechins
Fights oxidative stress, protects muscle cells, and aids recovery.
Chromium / Selenium
Trace minerals supporting metabolism, growth, and recovery.
Usage
For maximum benefits, it's essential to use Extreme Endurance daily, much like a multivitamin. Research shows that the longer you take it, the greater the results, so make a commitment to consistent daily use—we've even had athletes relying on it for over 14 years without interruption.To achieve optimal results, follow these simple guidelines:
Morning: Swallow 3 tablets of Extreme Endurance with or without food.
Evening: Swallow 3 tablets of Extreme Endurance with or without food.
We recommend avoiding stand-alone magnesium supplements while using Extreme Endurance, as adding 300 mg or more isn't advised. You'll already receive an ample daily dose of magnesium from the 6 tablets.
Take a Look Inside
Informed Sport
CertifiedFirst US company to use trusted global testing method
Gluten Free Preservative Free
Safe for celiacs and no bad fillers
Zero Banned
IngredientsIt’s an all-natural, electrolyte mineral supplement
Made In
The USAProudly made and owned in the USA
Ingredients at Research Level Dosages
Hormone-Free
Third Party Tested
Non-GMO
Alpha-GPC
Elite mental + physical performance amplifier (100% FDA full “GRAS”)
Beet Root Powder
Promotes energy, stamina and boosts cognitive function*
Green Tea Extract
Quick clean energy in the form of caffeine (120mg)
L-Theanine
Promotes mental sharpness, mood & mental endurance*
L-Tyrosine
Melts away stress and boosts mood + mental alertness*
For Elite & Aspiring Athletes
+2,600 5-STAR REVIEWS
Slide 1 of 9Focus Up
Proven Results In 7 days
ONE WEEK CHALLENGE
See proven results in 7 days
Day 1
Record workout before taking Extreme Endurance
Day 2-7
Start taking Extreme Endurance and don't skip any days
Day 8
Retest workout from Day 1 and see your performance increase
Day 8+
Maintain daily dosage for compounding benefits
VS. The Competion
Benefits
Others
Unbiased & rigorous scientific research
Reduces lactic acid by 26%
Reduces oxidative stress by 39%
Informed-Sport Certified
Proudly U.S.A made & owned
ALL NATURAL PERFORMANCE ENHANCER
ALL NATURAL ENERGY
Non-gmo, soy & dairy free, no artificial colors, flavors or artificial sweeteners, no caffeine or stimulants
Scientific Efficacy
Proven by rigorous scientific research and tested by unbiased 3rd parties.
State-of-the-Art Manufacturing
We only partner with Good Manufacturing Practice (GMP) certified and/or equivalent facilities.
Accessibility for All
We strive to make our product line available to athletes of all abilities!
Certified By Informed Sport
3rd party tested to guarantee free of banned substances
60-Day Guarantee
FAQS
How quickly will I see results with Extreme Endurance?
Extreme Endurance will be in your system and working within 48-72 hours. We can confirm this from 12+ years of clinical testing.
Can I take Extreme Endurance with other supplements?
Extreme Endurance can be taken together with almost every other supplement but you do not need to take any product containing Beta Alanine when taking Extreme Endurance.
Please reach out to info@xendurance.com for specific inquiries.Do I need to take Extreme Endurance with food?
You do not need to take Extreme Endurance with food.
Is Extreme Endurance certified drug free?
Extreme Endurance was the very first US sports nutrition supplement certified drug free by LGC; Informed Sport.
LGC is a world-renowned sports doping control and research laboratory, with over 50 years of expertise in anti-doping in sport. LGC has published over 300 scientific papers on methods for the detection of trace levels of substances that are prohibited in sport and has over 450 man-years of research into doping control.
LGC has been testing supplements and ingredients on behalf of reputable manufacturers and suppliers for over 15 years. It has tested tens of thousands of samples during this time and has also carried out a number of research studies to explore the prevalence of contamination with prohibited substances in products and ingredients.
LGC's research into supplements and contamination also includes several administration studies to investigate the levels of prohibited substances that could cause an athlete to fail a doping test. These have been published in peer-reviewed scientific journals. As a doping control laboratory, LGC works directly with sports authorities, national anti-doping organizations, and national governing bodies worldwide.
Is Extreme Endurance certified drug free by the NCAA?
There are no NCAA approved supplement products. The NCAA does not approve supplements. Since 2007, Xendurance has had thousands of NCAA student-athletes take Xendurance products and rely on the Informed-Sport certification which is a global testing method for banned substances. To learn more please find the Informed-Sport link.
Can Extreme Endurance be taken with caffeine?
Over the years we have found that some people have a very acidic diet and their diet may interfere with the dissolution of the product in the small intestine. On the other hand, one of our athletes drinks 12 cups of coffee per day and lives on Extreme Endurance with great results! Everyone is different but the few that have had issues cleared up the dissolution problem by limiting acidic drinks, red meat, and coffee when taking Extreme Endurance.
We now encourage people to take their caffeine within an hour prior to or after taking their tablets just as a precaution.Do I need to cycle off Extreme Endurance?
You don’t cycle with Extreme Endurance. You take it consistently, like a multivitamin; for training, performance, heart-lung function, and for better body pH and alkalinity.
Can an athlete take Extreme Endurance if under the age of 18?
We encourage a parent to email info@xendurance.com and provide the sport and activity level of their child and their age, and weight. We can then provide better guidance for the parent as to the experience we have seen with athletes using the product under the age of 18. We do not recommend anyone under the age of 14 use Extreme Endurance.
When should you take Extreme Endurance? What time of day?
The most important thing to remember when taking Extreme Endurance is to take it consistently like you would a multivitamin. You can split the morning and evening dosage to the time of the day that works best for you. Ex; If you take it at 6 am and 5 pm, we encourage you to try to take it around 6 am and 5 pm everyday. You can take it with or without food.
What is a “Load Dose”?
The normal dose of Extreme Endurance is 6 tablets per day: 3 in the morning and 3 in the evening. For athletes that will be having a significant event or an “extreme” event such as an ultra-distance race, a state meet, or an event that is more intense than your normal events, we recommend what is called a “load dose”. A load dose is taken 7-10 days out from the event and you increase the dosage to 8 tablets per day: 4 in the morning and 4 in the evening and you take 8 tablets for one day after the event and then drop back down to the normal dose of 6 tablets per day. In 2008, our pro-triathletes started using a load dose and they informed us they had their best results bumping up their dosage, so this is why we tell competitors in every sport to use the load dose.
What sports will benefit from using Extreme Endurance?
Since 2008 we have heard from every type of athlete, in every type of sport with the exception of “curling”. We are still waiting for a curler to come forward. So if you are a curler we want to hear from you! Runners, Ultra-distance, Marathon, Triathletes, Crossfit, Cycling, Jiu Jitsu, Swimming, Tennis, Golf, Surfing, Football, Basketball, Baseball, Motorcross, Paddleboarding, Skiing, Boxing, Rugby, Rock Climbing, Wrestling, Hockey - just not curling yet....
Build a better Habit
Swap out the old and in with the new.
Proudly owned, manufactured and shipped in the USA, since 1998.
Get in touch: info@xendurance.com*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.
