Air Force PAST Underwater Test: How to Not Panic
The Air Force PAST underwater test is the event candidates fear most. The PAST is now officially the Initial Fitness Test (IFT), and the underwaters are two 3-minute cycles. In each one you push off the wall, swim 25 m underwater, then surface swim back to the start with any stroke. Break the surface during the underwater and you fail the entire test. It's not a fitness event. It's a composure test with lung capacity attached.
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Why Candidates Panic
A few seconds into a breath-hold, rising CO₂ creates a strong urge to breathe. Untrained candidates read that as suffocation. They panic. They surface.
A 25 m underwater swim takes most candidates well under 30 seconds. The urge to breathe arrives long before you are actually low on oxygen, and learning to stay calm through it is the skill. That is also why it is dangerous: hypoxia can cause a blackout with little warning, which is why every rep in water needs a trained spotter.
The 3 Training Pillars
- CO₂ tolerance tables: Train your body to accept CO₂ accumulation without panicking
- O₂ capacity tables: Extend actual breath-hold duration
- Dry-land technique drills: Practice streamlined position out of water
CO₂ Tolerance Table (2-3x per week)
Do these DRY, sitting or lying down. Never in the water, and never alone in a pool.
- Hold breath 1:00, rest 1:45
- Hold 1:00, rest 1:30
- Hold 1:00, rest 1:15
- Hold 1:00, rest 1:00
- Hold 1:00, rest 0:45
- Hold 1:00, rest 0:30
- Hold 1:00, rest 0:15
- Hold 1:00 final
Rest decreases each round, so CO₂ accumulates. Your brain learns it's tolerable.
O₂ Capacity Table (1-2x per week)
Build actual lung capacity.
- Hold 1:00, rest 2:00
- Hold 1:15, rest 2:00
- Hold 1:30, rest 2:00
- Hold 1:45, rest 2:00
- Hold 2:00, rest 2:00
Rest stays constant. Hold times increase. Your max breath-hold grows.
Technique in the Water
Streamlined position: Arms extended forward, biceps squeezing ears, legs straight, toes pointed. Minimal drag.
Kick discipline: Small, fast dolphin kicks or efficient breaststroke pulls. Never wide scissor kicks (wasted energy).
Gaze forward, not down: Keeps the body aligned horizontally.
No premature exhalation: Exhale only when you're ready to surface at the end of the 25m. Exhaling mid-swim ends the breath hold fast.
Pool Training Protocol
Always with a qualified swim coach or trained dive buddy. Never alone: shallow water blackout is real and kills healthy athletes.
- Session 1-2: Practice 25m underwater at pool depth 3-4 feet
- Session 3-4: Full 25m underwater, then an easy surface swim back to the wall
- Session 5+: The test format: two 3-minute cycles, each a 25 m underwater swim followed by a surface swim back to the start
Mental Game
On a 25 m underwater, the early urge to breathe is uncomfortable, not an emergency. Candidates who pass treat it as information and stay smooth. That is different from pushing past your limits: blackout can come without warning, so never extend breath-holds beyond what your coach programs, and surface if anything feels wrong in training.
Score your full PAST with underwaters included →
The Real Warning
Never train breath-holds alone in water. Ever. Shallow water blackout kills otherwise healthy, strong swimmers every year. Pool work requires a qualified buddy or coach. Dry-land CO₂ tables are where the real adaptation happens anyway.
