Workout

Warm-up (600)
400 free
200 kick

Set (600)
6 X 100 on 1:40
...descend 1-3, 4-6

Set (1500)
5 X 100 build on 1:35
4 X 100 build on 1:30
3 X 100 build on 1:25 
2 X 100 on 1:20
100 FAST

Set (500)
10 X 50 on 1:00
..alternate kick swim by 25's

Cool-down (200)
200 EZ