Marathon Swimming Federation

The Marathon Swimming Federation (MSF) is the international organization that oversees and governs long-distance open water swimming competitions worldwide. It sets rules, standards, and safety protocols for marathon swims, typically covering distances beyond 10 kilometers, often across lakes, rivers, or open ocean. The federation promotes the sport’s integrity, organizes major events, and ensures consistent regulations to maintain fairness and athlete safety. By uniting national swimming bodies, the MSF helps develop and standardize marathon swimming as a recognized, competitive sport around the globe.