The Endurance-Boosting Supplement that Every Runner Needs

#1 Improve Workout or Race Time

Clinically proven to reduce lactic acid and improve running performance - Extreme Endurance is a must have for any runner.

Whether you are gearing up for your next marathon or want to set a new 5K PR, this is a must have product to put to the test.

#2 Increase VO2 Max 

Increase your pace and be able to hold on. Extreme Endurance makes it feel like you have a third lung while preventing your muscles from tightening up.

#3 Trusted By World Class Runners

Contributing to personal records, American records, and World Records - Extreme Endurance has been used by runners for over a decade to help break barriers.

Donavan Brazier set the American Record in the 800m after being on Extreme Endurance for two months.

#4 Improve Recovery Time / Less Muscle Soreness

Feels like putting on a brand new pair of running shoes every day.

Look forward to putting in more miles when you don't feel yesterdays workout.

By reducing Creatine Kinase (CK) levels by 6x means your muscles recover better during workouts and help speed up recovery.

#5  Clinically Proven + Tested By Informed Sport

Supported by 12 Clinical Studies and certified free of banned substances by Informed Sport. It feels like a performance enhancing drug, but isn't.

Goodbye Soreness

Hello Performance


Increase Performance

Improve Power & Vo2 Max 10-25%

Recover Faster

6X Reduction of Creatine Kinase

Less Muscle Soreness

26% Reduction in Lactic Acid

Endorsed by:

Trusted by

World Class Athletes

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.

As proven in:

Journal of Athletic Achievement

ENA Conference, Vienna Austria

ENA Conference, Vienna Austria (2010)

Journal of Athletic Achievement (2016)

How to

Improve in 72 Hours

Perform a baseline workout.

Take 3 tablets in the AM and repeat in the PM. Train regularly.

Feel benefits in 72 hrs and redo baseline workout.

Test with the


Perform a baseline workout

Take 3 tablets in the AM & PM.
Train regularly

Redo baseline workout in 7 days + feel the results



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60 Day Starter Pack



SAVE $63.95

Experience the World’s #1 Supplement for Stamina, Performance & Recovery.

Try the 60 Day Pack and get:

FREE Omega+D3

FREE $25 Gift Card

2 x Packs of Extreme Endurance

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Over 10+ years

Customer Reviews

Based on 1456 reviews
Craig Nunes
Extra speed

Set so many new P.Rs cycling with this product.

Wow, that's amazing! Thank you for sharing your experience with Extreme Endurance! We hope you continue to see great improvements with our product. Keep crushing those goals!

Cheryl Patterson
Good Stuff

My husband and I were both taking it along with another friend. We all noticed less fatigue after big workouts. Unfortunately, I started to develop some digestive issues so quit using it but have no clue as if the product was the culprit. So, other two users experienced no adverse reactions. I liked the product but will try again later.

Thank you for your review! We're thrilled to hear that you've noticed an improvement in your post-workout recovery since taking Extreme Endurance. While we cannot confirm if our product was the cause of the digestive issues, we always recommend consulting with your doctor before starting any new supplement. We appreciate your feedback and hope you will give our product another try in the future.

Barbara Loparo
Extreme endurance!!

I have come a long way since starting to take these ! My runs are much better and smoother! Great product!!!!!!

Wow, that's amazing! We're so happy to hear that Extreme Endurance has helped improve your runs and overall performance. Thank you for making us part of your fitness journey! Keep up the amazing work!

Wendi Glisson
Xendurance game changer

I am experiencing a noticeable difference and how I feel when I’m training when I’m going hard recovery is awesome and I’ve been crushing workouts

Awesome! We are thrilled to hear that you are loving our Extreme Endurance product! We hope you continue to see great improvements with our product. Keep crushing those workouts!

Marvin Green

This stuff is absolute magic, when they say there's no magic pill for cardio, this is it. I literally have to stop exercising on my own, the lactid acid is non exsist

Judge.me YouTube video placeholder

Awesome! We're glad to hear that Xendurance is working well for you! We hope that you'll continue to use it to help improve your overall fitness and well-being!

Jorge A Cabrera

I ha e been very soar lately...finally endurance arrived. Been taking them for the last two days. Had my first long distance run in a while..wow...the way it just keeps your body from wanting to keep going, not tired just energized. This stuff is amazing it really works...

Thank you for sharing your positive experience with our product, Extreme Endurance. We are so glad to hear that it has helped you during your long distance run and provided you with sustained energy. We appreciate your feedback and hope that our product continues to support your endurance. Keep up the great work!

Supplement facts

NON-GMO / Gluten Free / Preservative Free.

Contains no Yeast, wheat, corn, milk, eggs, soy, artificial colors, sugar, starch or flavorings.

100% Guaranteed

Backed by the XND Promise

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 Drug Free By Informed Sport

3rd party tested to guarantee free of banned substances

60-Day Money
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