Workout

Warm-up (900)
300 swim
4 x 150 
...50back/150free 
...rest 10-15 sec.

Main Set (2400)
300 
...50 kick/200 swim/50 kick 5:10
4 x 100 1:50 odd: stroke even: free
2 x 50 free :45

300 same
3 x 100 1:40 odd: stroke even: free
4 x 50 on :45

300 same
2 x 100 on 1:30 odd: stroke even: free
6 x 50 on :45

Cool-down
100 ex