Workout

Warm-up (600)
2 rounds
100 swim/100 drill/100 kick

Set (600)
8 x 75 on 1:30 
…25 free/25 stroke/25 kick
 
Set (1800)
(3 rounds)
3 x 50 build on :55
150 on 2:30, 2:20, 2:30
...descend 1-3 by rounds  
2 x 100 on 1:45
2 x 50 FAST on 1:00

Cool-down (200)
200 ez choice