-and-seconds-per-mile pace.5KTRAINING PHASE:BASE (4 WEEKS)Speed sessions:4 to 12 hill sprints Distance sessions:5- to 10-mile variable-pace runTRAINING PHASE:BUILD 1 (3 TO 4 WEEKS)Speed sessions:4 to 12 x 400m @ 1-mile pace with 2 minutes recoveryDistance sessions:4 to 12