Stop running your easy days too hard and your hard days too easy. Tackling 26.2 miles requires safely building your aerobic engine without injury. Designed specifically for intermediate runners looking to improve their marathon time, this 24-week plan uses the proven 80/20 Endurance methodology. You will run 5 days a week, with 1 day of cross-training, introducing a critical 5th day of running impact to build structural resilience and expand VO2 Max specific pacing. To elevate fitness, you'll ...