Respected running and fitness expert Matt Fitzgerald explains how the 80/20 running program—in which you do 80 percent of runs at a lower intensity and just 20 percent at a higher intensity—is the best change runners of all abilities can make to improve their performance. With a thorough examination of the science and research behind this training method, is a hands-on guide for runners of all levels with training programs for 5K, 10K, half-marathon, and marathon distances. In you’ll discover how to transform your workouts to avoid burnout. • Runs will become more pleasant and less draining • You’ll carry less fatigue from one run to the next • Your performance will improve in the few high-intensity runs • Your fitness levels will reach new heights promotes a message that all runners—as well as cyclists, triathletes, and even weight-loss seekers—can embrace: Get better results by making the majority of your workouts easier.