Featuring the proven 80/20 intensity balance described in Matt Fitzgerald's bestselling book 80/20 Running, this 5K Level 3 training plan will provide you with the same workout structure used by the most successful runners in the world. TARGET ATHLETE This plan was designed runners who are ready to take their training load up a notch or two in order to improve their 5K time. Before you begin the plan, build your training to the point where you are running at least three times per week. 100% ...