Workout

Warm-up (500)
2 rounds
100 swim/100 drill/50 kick

Set (600)
12 x 50 build on :55
…4 cb

Set (1800)
6 x 200 on 3:10
…build by 50
4 x 100 on 1:30 
…descend 1-2
4 x 50 on 1:30 
…FAST!

Cool-down (200)
200 easy