Intensify block, weeks 17 to 21

Week 21 of BUD/S Prep

The long run reaches eight miles and the long swim 3000 yards. Last week of the intensify block; core work moves to its final tier next week.

The six sessions

DayCardioStrength
MondayLong slow distance run8 milesUpper/Core
TuesdayContinuous high-intensity swim2 x 16 minLower/Push-Sit-Pull
WednesdayInterval run10 repsCore/Push-Sit-Pull
ThursdayLong slow distance swim3000 yardsCore/Push-Sit-Pull
FridayContinuous high-intensity run2 x 16 minUpper/Core
SaturdayInterval swim10 repsLower/Push-Sit-Pull

What changes from week 20

  • Monday, long slow distance run: 7.75 miles to 8 miles
  • Thursday, long slow distance swim: 2900 yards to 3000 yards

The intensify block

Weeks 17 to 21 push the long sessions toward race-plus distances: runs of seven to eight miles and swims of 2600 to 3000 yards. Continuous high-intensity blocks lengthen again. A candidate who has stayed healthy through this block is in a strong position; a candidate carrying a nagging injury should back off the long days rather than the intervals, because the intervals are what move PST scores.

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