August 2 - 250 athletes will jump from the ferry into the freezing Hardangerfjord, beginning a journey that will test their limits across fjord, mountains, and mind. As they take on the Zalaris Norseman Xtreme Triathlon—known as the world’s toughest triathlon—we have a new partner by our side: Defender.

Athletes from 38 nations will be ready to do the iconic jump from the ferry to participate in Zalaris Norseman Xtreme Triathlon and XTRI World Championship on August 2, 2025.

After Zalaris Norseman Xtreme Triathlon, the finish line isn’t the end for science. For researcher Martin and the Norseman Research Team, it’s the beginning. By analyzing the blood biomarkers of athletes before and after the race, they’re uncovering how the body reacts—and recovers—from one of the most extreme endurance tests on the planet.