Stop running your easy days too hard and your hard days too easy. Designed specifically for novice runners or those looking to step up their volume safely, this 12-week plan trades a rest day for a low-impact cross-training day. This expands your aerobic base and fat-burning engine without the pounding of extra running miles. Built on the proven 80/20 Endurance methodology, you will spend 80% of your time in easy aerobic base-building (Zone 2) and 20% executing math-driven intervals to raise ...