Workout

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

Set (500) 
10 x 50's on 1:15
...odd: 25 breast pull with dolphin kick/25 stroke
...even: 25 under water/25 ez free

Set (1600)
400 IM - reverse order on 7:00
...50 swim/50 drill
2 x 200 Free on 3:00
...negative split  
4 x 100 IM on 1:45
4 x 100 Stroke on 2:00

Set (400)
400 Kick 
...every 3rd 25 BLAST kick

Cool-down (200)
200 easy