Caribbean Reef Octopus

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This set simulates a triathlon swim where the pace is always fast at beginning, then it settles after a while and you get into pack, then it can tend to finish strong as people starting thinking about getting out of the water. The kick is to simulate getting on the bike.

Warm Up
400 easy swim

Set 1
300 alternate 50 free/50 non-free, smooth @ :20 rest
200 kick with board @ :20 rest
100 IM smooth @ :20 rest
(600)

Set 2
10 x 50 build @ 1:00 (get faster throughout each 50m effort, last 5m hard with no breathing)
(500)

Set 3
6 x 450 m (400 swim, 50 kick with Board). The 400 swim is 100m hard, 250 m moderate, then 50 m hard straight into 50 m kick hard with board. Make that first 100 truly hard (to simulate the beginning of a race) and settle into the 250 at a comfortable pace, not loafing (~60-70% effort).

200m easy backstroke recovery

(2900)

Set 4
800 pull - A ladder as follows: 25 hard, 25 steady, 50 hard, 50 steady, 75 hard, 75 steady, 100 hard, 100 steady, 75 hard, 75 steady, 50 hard, 50 steady, 25 hard, 25 steady.
(800)

Make sure there is a pace change between steady and hard, again to simulate having to speed up to pass people, etc during a race.

Warm down
300 easy

Total: 5,500

Source