Warm-up:
1600m Easy Run with 4x100m sprints
Sprint Workout:
6x400m Sprints
(400m jog recovery)
Cool-down:
1600m Easy Run
Note: This is a continuous workout from warm-up to cool-down. 4x100m sprints should be done prior to the Sprints.
Post distance and total time to comments:
SPD CrossFit 
4.91 miles (47:14 minutes)