Training for the 15-Meter Rule: Why Underwater Work Pays Off

How much underwater time can I get away with?

If you've ever watched a race and wondered why the best swimmers seem to glide forever after the start or turn, the answer is the 15-meter rule. In every stroke, you may stay fully underwater for no more than 15 meters after the start and each turn (World Aquatics). That's the ceiling. But here's the thing: most age-group and even many college swimmers never get close to that limit. They pop up too early, lose momentum, and give back precious seconds. We see it in every practice and every meet.

Why underwater speed is your secret weapon

Underwater dolphin kicking is faster than swimming on the surface for most athletes. It's why the best in the world spend so much time underwater. The rule is clear: you get 15 meters of pure speed after every wall. That's 15 meters where drag is lower and your body position can be streamlined. If you can't hold your underwater phase to at least 12 or 13 meters, you're leaving time on the table. The fastest swimmers in history—think Michael Phelps, who won a record eight gold medals at the 2008 Beijing Olympics (World Aquatics)—built their reputations on devastating underwaters. You don't need that level of talent, but you can train the same skill.

Step one: Master the breakout

Before you worry about distance, get the breakout right. In backstroke, your head must break the surface at or before the 15-meter mark after the start and each turn, and then you must stay on the surface until the next turn or finish (World Aquatics Swimming Rules Reference Card). In breaststroke, the head must break the surface before the hands turn inward at the widest part of the second stroke after the start or turn (World Aquatics Swimming Rules Reference Card). That's a specific technical cue. In practice, we have swimmers do a simple drill: push off the wall in a streamlined position, count your dolphin kicks, and mark where you surface. Most beginners surface at 7 or 8 meters. With work, you can push that to 12 or 13. The rule isn't a limit—it's a target.

Step two: Build your underwater kick capacity

The limiting factor for most swimmers is not technique but lung capacity and leg endurance. We use a simple set: 10 x 25 meters on a short rest interval, all underwater dolphin kick with a monofin, focusing on staying smooth and relaxed. Start with 10 kicks per 25, then build to 15, then 20. Over a few weeks, you'll feel the difference. But here's the caution: don't sacrifice your stroke. The rule says you can stay underwater for 15 meters, but if you come up gasping and your first three strokes are trash, you've lost the advantage. We tell our athletes: better to surface at 12 meters with a clean stroke than at 15 with a blown-up one.

Step three: Apply it to your race strategy

Imagine you're a 200-meter freestyler. You have a start and three turns. That's four opportunities to use your underwater phase. If you add just 2 meters of underwater distance per wall, that's 8 meters of free speed per race. Over a 200, that's a significant chunk. The same logic applies to backstroke, where you can be fully submerged within the final 5 meters while reaching for the finish (World Aquatics Swimming Rules Reference Card). That's a tactical move: you can stay under a bit longer to hit the wall with a full stroke. In breaststroke, you get a single butterfly kick after the start and each turn (World Aquatics). Use it. It's legal, and it adds propulsion.

Step four: Respect the rules and train the details

This is where most swimmers get disqualified: they break the rule by popping up at 16 meters, or they take an extra dolphin kick in breaststroke. The rule is strict. In backstroke, the turn must be started immediately after turning onto the breast, and you must leave the wall on your back (World Aquatics Swimming Rules Reference Card). In breaststroke, your feet must be turned outward during the propulsive part of the kick, and a downward butterfly kick during the stroke is not permitted (World Aquatics Swimming Rules Reference Card). These are the details that separate a legal race from a DQ. We have our swimmers video their starts and turns every week. It's the only way to see what you're actually doing.

Bottom line

The single best move you can make in training is to dedicate 15 minutes per session to underwater work, with a focus on distance and control. Aim to hit 12-13 meters legally on every start and turn, and you'll shave seconds off your times without changing anything else. The rule is your friend—use it.

Sources

• World Aquatics - https://www.worldaquatics.com
• World Aquatics Swimming Rules Reference Card (2023-2025) - https://eastswimming.org/wp-content/uploads/2024/04/WA-Swimming-Reference-Card_13072023-Large-Print-Bold.pdf
• World Aquatics: About World Aquatics - https://www.worldaquatics.com/about