Workout

Warm-up (600)
400 Free
200 Kick

Set (600)
6 x 100's on 1:30
…neg split

Set (1200)
12 x 100's on 1:25
...build

Set (800)
8 x 100's on 1:20
descend 1-4

Set (200)
4 x 50's on :40
...fast

Cool-down
200 EZ