Workout

Warm up (500)
400 free
100 IM

Set (450)
3 rounds
3 x 50 on 1:00
50 kick, 50 kick, 50 swim) 
 
Set (450)
3 x 150 on 2:15  
...breathing 3/5/7 by 50

Set (2000)
(150, 125) x 4 rounds
All on 2:00
(125, 100) x 4 rounds
All on 1:30

Warm down (100):
100 EZ