Workout

Warm-up (400)
400 choice
75 swim/25 kick

Set (600)
12 x 50 drill on :55
...3 each stroke  

Set (1500)
5 rounds
100 on 2:00 fast
75 on 1:30 faster
50 on 1:00 faster
25 on :30 all out!
...Descend each set  
1 min rest between rds
  
Cool-down (300)
100 kick
200 swim