Workout

Warm-up (500)
2 rounds
200 free/50kick

Set (600)
3 rounds  
2 x 50 build on :45
100 free on 1:30
...descend 1-3 by rds

Set (1200)
300 on 4:30
…last 50 fly
4 x 150 on 2:15
...d1-4
300 on 4:30
…last 50 back

Set (900)
4 x 100 on 1:15
...d 1-4
300 on 4:30
…last 50 breast
4 x 50  FAST on 1:00
...25 kick/25 swim

Cool-down (200)
200 easy