500-Yard Swim
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.
Event Rules and Standards
Candidates swim 500 yards (10 laps in a 25-yard pool) using sidestroke or breaststroke — freestyle is not permitted. The minimum qualifying time is 12 minutes 30 seconds, while competitive times are typically under 9 minutes. The swim is the opening event of the PST, setting the tone for the rest of the assessment.
Why Sidestroke and Breaststroke
The PST restricts strokes to sidestroke and breaststroke because these are the combat swimming strokes used in NSW operations. The combat sidestroke (CSS) is the preferred technique — it's efficient, low-profile in the water, and the stroke candidates will use extensively during BUD/S pool and ocean evolutions. Training with CSS from the start of preparation builds the stroke efficiency needed later.
Swim Training in the 26-Week Program
The NSW preparation program develops swim fitness through three modalities: LSD swims for building endurance and stroke efficiency, CHI swims for sustained high-intensity output, and interval swims for speed development. Swimming alternates with running across the training week, ensuring candidates develop both land and water cardio capacity in parallel.
Learn the combat sidestroke early. Breaststroke is allowed but far less efficient — you'll burn more energy for slower times.
Related Terms
The Physical Screening Test (PST) is the standardized fitness assessment used by Naval Special Warfare to evaluate candidates for SEAL training. It measures performance across five events: 500-yard swim, push-ups, sit-ups, pull-ups, and a 1.5-mile run, each with minimum and competitive score thresholds.
The combat sidestroke (CSS) is a hybrid swimming technique developed for military applications that combines elements of sidestroke, freestyle, and breaststroke. It is the preferred stroke for the PST 500-yard swim and the primary swimming technique used throughout BUD/S training and NSW operations.
Long Slow Distance (LSD) training is a cardio methodology that emphasizes sustained, moderate-intensity effort over extended durations. In BUD/S preparation, LSD sessions build the aerobic base required for long swims, runs, and the prolonged physical output demanded throughout SEAL selection.
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.
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