Swim Interval Pace Chart
The swim interval pace chart is the swim half of Table 1 in the NSW Physical Training Guide. It converts your most recent 500-yard swim time into a target 100-yard repeat time and a recovery window for the Saturday interval swim, so the intensity of every interval session tracks your tested fitness.
How to Read the Chart
Find the row that contains your current 500-yard swim time. The middle column gives the time window for each 100-yard repeat, and the right column gives the recovery window between repeats. A candidate who swims 500 yards between 10:00 and 10:30 should swim each 100 yards in 1:58 to 2:04 and recover for 3:56 to 5:10 before the next one. The repeat window is about 2 seconds faster than your base 100-yard pace, and the recovery is 2 to 2.5 times the repeat time. Recovery is active: keep moving with an easy stroke rather than holding the wall, so the heart rate comes down without the body going cold.
How the Brackets Progress
The chart uses 16 brackets of 30 seconds each, from a 500-yard time of 8:00 to 8:30 at the top to 15:30 to 16:00 at the bottom. Each bracket shifts the repeat window by 6 seconds and the recovery window by 12 to 15 seconds. The fastest bracket asks for 1:34 to 1:40 repeats with 3:08 to 4:10 recovery. The slowest asks for 3:04 to 3:10 repeats with 6:08 to 7:55 recovery. The PST minimum for the swim is 12:30, so a candidate at the minimum sits in the 12:00 to 12:30 bracket with 2:22 to 2:28 repeats, and each 30-second improvement in the test moves them up one row.
Using the Chart Across the Program
The chart sets pace and THE_PLAN sets the repeat count, which starts at 4 in week 1 and reaches 10 in week 13. Swim every repeat in the combat sidestroke or breaststroke, the strokes the PST allows, because a pace earned in freestyle does not transfer to the test. Retest the 500-yard swim periodically and move up a bracket only when the test says so. The guide notes that a candidate with a swim slower than 10:35 while running well should weight training toward the water. For that candidate, the chart is the tool that keeps the extra swim sessions at a productive intensity instead of a guess.
Swim interval paces by current 500-yard time
| Current 500-yard time | Interval repeat | Recovery |
|---|---|---|
| 8:00-8:30 | 1:34-1:40 | 3:08-4:10 |
| 8:30-9:00 | 1:40-1:46 | 3:20-4:25 |
| 9:00-9:30 | 1:46-1:52 | 3:32-4:40 |
| 9:30-10:00 | 1:52-1:58 | 3:44-4:55 |
| 10:00-10:30 | 1:58-2:04 | 3:56-5:10 |
| 10:30-11:00 | 2:04-2:10 | 4:08-5:25 |
| 11:00-11:30 | 2:10-2:16 | 4:20-5:40 |
| 11:30-12:00 | 2:16-2:22 | 4:32-5:55 |
| 12:00-12:30 | 2:22-2:28 | 4:44-6:10 |
| 12:30-13:00 | 2:28-2:34 | 4:56-6:25 |
| 13:00-13:30 | 2:34-2:40 | 5:08-6:40 |
| 13:30-14:00 | 2:40-2:46 | 5:20-6:55 |
| 14:00-14:30 | 2:46-2:52 | 5:32-7:10 |
| 14:30-15:00 | 2:52-2:58 | 5:44-7:25 |
| 15:00-15:30 | 2:58-3:04 | 5:56-7:40 |
| 15:30-16:00 | 3:04-3:10 | 6:08-7:55 |
Time the repeat from push-off to hand on the wall, the same way the PST is timed. A watch started on the first stroke hides two seconds per length and puts you in a bracket you have not earned.
Related Terms
The Interval swim is the Saturday cardio session in the 26-week NSW preparation program. It consists of repeated 100-yard efforts at a pace slightly faster than your current 500-yard swim pace, separated by recovery periods, and the repeat count grows from 4 in week 1 to 10 by week 13.
Interval training is a cardio method that alternates between high-intensity work periods and active recovery periods. In the NSW preparation program, interval sessions target running and swimming speed by training the body to sustain faster paces through repeated timed efforts.
The 500-yard swim is the first event of the Physical Screening Test (PST) and measures a candidate's aquatic endurance. Performed using either the combat sidestroke (CSS) or breaststroke, it tests the sustained swimming capacity required for BUD/S water-based evolutions.
The run interval pace chart is Table 1 of the NSW Physical Training Guide. It converts your most recent 1.5-mile run time into a target quarter-mile repeat time and a recovery window for the Wednesday interval run, so every candidate trains at an intensity calibrated to their current fitness.
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