Workout

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

Set(600)
12 x 50 free on :50
...descend 1-3/4-6

Set (2000)
2 rounds  
4 x 25 on :30  1-4 IM 
4 x 50 on 1:00  repeat theme
4 x 75 on 1:15  repeat theme
4 x 100 IM on 1:45

Set (600)
3 x 200 on 3:30
...150 free/50 kick
...100 free/100 kick
...50 free/150 kick

Cool-down (200)
200 moderate to EZ choice