IRONMAN Chattanooga

IRONMAN Chattanooga is a full-distance triathlon held in Chattanooga, Tennessee, on September 27, 2026, organized by IRONMAN. The single event combines a 3.8 km swim (2.4 miles), a 180 km bike leg (112 miles) and a closing marathon (26.2 miles), in that order, for one of the longest one-day formats in endurance sport.

If you are coming to this race from a running background, the marathon is where you will feel most at home, but it is also where the day is decided. Running 26.2 miles after five or six hours on the bike is nothing like running a stand-alone marathon, so your training should include brick sessions where you run straight off the bike, and long rides that build the durability the run demands. A typical build for a full-distance triathlon runs 20 to 30 weeks, with the longest weeks stacking a 5-to-6-hour ride and a 2.5-to-3-hour run. This is a goal for athletes who already have a half-distance triathlon or several marathons behind them rather than a first multisport event.