Workout

Warm-up (600)
300 free, 100 kick
200 drill

Set (800)
2 x 400
1) alt. 50 back/50 free 
:30 rest
2) all free, descend by 100s

Set (1800)
300 free on 4:30
4 x 200 on 2:50/3:10/2:45/3:15
300 free on 4:30 
...faster than the first
4 x 100 on 1:20

Cool-down (200)
200 moderate to EZ