Featuring the proven 80/20 intensity balance described in Fitzgerald and Warden's bestselling book 80/20 Triathlon, IRONMAN® Level 1 training plan will provide you with the same workout structure used by the most successful triathletes in the world. TARGET ATHLETE This plan is designed for any triathlete, beginner or experienced, or masters athletes who need or prefer a low-volume training plan for the Ironman distance. Before you begin, you should be comfortably able to swim and run for 45 ...