Base Builder 16 week Plan 3 Days a week: 10 to 20 Miles (16k to 32k) Training Plan

This comprehensive 16-week base-building plan is engineered for runners looking to safely scale up their weekly volume from 10 miles (16 km) to a robust 20 miles (32 km) a week. It is uniquely structured for runners preparing to launch into an accelerated marathon training plan or an advanced half-marathon program. Built specifically for those who have been running consistently for at least 12 months, this program splits your volume over just 3 days per week—making it ideal for busy schedules, time-crunched athletes, or those managing structural recovery. Utilising the scientific 4-week adaptation method to protect your joints, your body will spend 4 weeks stabilising at 10 miles, 4 weeks at 13 miles, and 4 weeks at 16 miles, before culminating in a final 4-week block holding steady at 20 miles. By the end of this plan, your aerobic engine will be fully primed for race-specific speed and distance.