Xendurance is a sports nutrition company that was founded in the United States in 2006, when the Xendurance formula (Extreme Endurance in the U.S.) was in development.

The parent company, Xendurance LLC, is located in Arizona. The goal of Xendurance LLC was to develop an all-natural, drug-free product that would improve an athlete’s performance by improving both aerobic and lactic acid threshold.

Xendurance also wanted to develop a formula that would safely reduce the “culprit” known as lactic acid.

Xendurance X FOOTBOKS®

In partnership with FOOTBOKS®, Xendurance provides quality products.

Xendurance products have been validated by FOOTBOKS®, its team and its sponsors.

The Xendurance brand was discovered with its “energizing gels” in the Footboks box of August 2021 so the composition was the following:

All these products are available individually in the Footboks store!


Informed-Sport is a quality assurance program for sports nutrition products, sports nutrition industry suppliers and supplement manufacturing facilities.

The program certifies that all nutritional supplements and/or ingredients that carry the Informed-Sport logo have been tested for prohibited substances by the world-class sports doping laboratory, LGC.

About the company

Lifespan International has recognized that athletes not only benefit from performance products, but also need to protect their health and immune systems from the trauma of rigorous training programs. With this in mind, Xendurance LLC is continually expanding its product line of multivitamins, omega and joint formulas, protein shakes and electrolyte drinks with unique formulas backed by science.

What sets Xendurance apart from other sports nutrition companies is that our flagship product, Xendurance, has been the subject of two published, Gold-Standard, third-party, double-blind, placebo-controlled, crossover studies. Many companies make substantial claims about individual ingredients, but Xendurance has been the subject of a published study of the entire formula, not just the ingredients. The “third party” testing is also important because it means that Lifespan International did not know or hire the institution that conducted the testing, and therefore no bias influenced the results of the study.

Xendurance was the first sports nutrition product manufactured in the United States to be certified drug free by HFL; INFORMED SPORT, the world renowned sports doping laboratory.

Xendurance continues to provide research and studies that prove its products.

Xendurance continues to be at the forefront of utilizing this science and success in providing sports nutrition to athletes of all sports, regardless of their level of participation or performance.