ATHX founders push niche UK fitness format toward global expansion

ATHX has gone from a UK-rooted competition idea to a circuit that now reaches Berlin, Dublin, Glasgow, Copenhagen, Birmingham, Barcelona, Marseille, Liverpool, Amsterdam and a Lisbon final. For CrossFit athletes watching the wider functional-fitness space, that makes it look less like a one-off brand play and more like a format that is trying to become a real international lane.

The company’s roots go back to 2023, when the teams behind Strength in Depth and National Fitness Games joined forces. Mark Hartnett-Morgan, the National Fitness Games co-founder who now serves as ATHX managing director, and Ollie Marchon, ATHX performance director, became the public faces of that merger. The official ATHX archive shows the project began with UK events in 2023, including Midlands, North, South and a Finals/Open in Birmingham, before adding London, Glasgow, Cardiff, Dublin and Liverpool in later seasons. That rollout matters because it shows ATHX has been built step by step, not bolted together for a single headline weekend.

The format itself is designed to feel familiar to anyone who has spent time in the functional-fitness world. ATHX describes its event as a 2.5-hour continuous fitness competition across six zones, with sections labeled Warm-Up, Strength, Refuel, Endurance, Recovery and MetCon. It also splits athletes into separate divisions, including ATHX, ATHX Pro, ATHX Lite, singles, pairs and mixed teams. That structure is the clearest sign that the brand wants everyday competitors in the room without forcing them onto the same floor as the fittest names on the start list.

The biggest proof of scale came in Miami Beach, where ATHX staged its first U.S. event on March 21-22, 2026. ATHX and outside coverage called it the company’s first-ever competition in the United States and the debut of its elite Invitational format. Hartnett-Morgan called Miami ATHX’s “first venture into the U.S.” and said the event was a step toward “raising the standard” of the format. The weekend also carried a broader festival feel, with fitness activities, classes and workshops alongside the competition itself.

Miami brought recognizable names with it, including Laura Horvath, Danielle Brandon, Khan Porter, Jonne Koski, Sydney Wells, Anikha Greer, Ty Jenkins and Jenifer Muir. It was produced with Breakwater Hospitality Group, presented with Adidas, and followed reporting that ATHX had signed a four-year global partnership with Adidas. That kind of backing suggests ATHX is not just chasing growth for growth’s sake. It is testing whether the functional-fitness market has room for another major circuit, one that borrows CrossFit’s mixed-modal DNA but packages it for a broader, more tiered global audience.