Caeleb Dressel's Start, Underwater, and Breakout: The Best 15 Meters in Swimming

In the final of the 100 freestyle at the 2019 World Championships in Gwangju, Caeleb Dressel reached the 15-meter mark in 5.11 seconds.

The average for the eight finalists was 5.55. The average for the five swimmers who didn't medal was 5.63.

Half a second. In a race he won by twelve hundredths, Dressel had built nearly his entire margin before taking a single freestyle stroke. He surfaced just shy of 15 meters already in the lead, went on to touch in 46.96 — the first sub-47 ever swum in a textile suit — and did the same thing again at the turn, taking 9.24 seconds from 45 to 65 meters while the rest of the field averaged 9.50.

Everywhere else in the race, Dressel was elite. Off the wall, he was in a different sport. That's why, years later, the start, the underwater, and the breakout are the three things his name is synonymous with — and why every sprinter should study them.

At Swim With Milo, we teach these as their own skill set, separate from the stroke. Here is what Dressel actually does in those 15 meters.

The Start: He Gives Away Reaction Time on Purpose

The obvious explanation for Dressel's start is a lightning reaction time. It's the wrong explanation.

In the Tokyo Olympic 50 free final, his reaction was 0.62 seconds — third-fastest among eight finalists, not first. Yet his lead at 15 meters was, in his coach's word, otherworldly. Reaction time is the easy number to quote. It isn't what makes the start.

What Dressel does differently is back-load his hips on the block. Most swimmers front-load their weight, which shaves hundredths off reaction time because the body has less distance to travel before the feet leave. Dressel gives those hundredths away deliberately. Loading the hips back produces a far more explosive launch and more acceleration through the air and the entry. He loses a fraction at the beep and wins it back several times over before he's five meters into the pool.

A biomechanical analysis of one of his fastest 50-yard swims, published by the University of Granada's aquatics research group, measured the result. His head entered the water 1.03 seconds after the start. He reached the 5-meter mark at roughly 1.33 seconds — at the same moment his feet entered the water, a hallmark of top-level starts. His time to 10 meters was 2.90 seconds. Alexander Popov's 10-meter time at the 1992 Olympics, one of the great starts of that era, was 3.33.

Want to find where your own start is bleeding time? Book a session with Swim With Milo and let's film it from the block down.

The Underwater: Patience First, Then a Kick Most Swimmers Don't Have

Here's the detail that separates a good underwater from Dressel's. He's one of the best dolphin kickers alive — and in the Tokyo 50 free final, he was one of the last swimmers to start kicking.

That's not a contradiction. The speed coming off an explosive start exceeds even elite dolphin-kick speed. Kicking too early means abandoning a perfectly streamlined bodyline and taking on drag in exchange for propulsion the swimmer doesn't need yet, because he's already moving faster than the kick could push him. Dressel holds the line, lets the momentum of the dive carry him, and only begins kicking once that speed starts to decay. SwimSwam's frame-by-frame of that race showed him entering the water behind a competitor and passing him in the very next frame — before either had kicked.

The entry itself is unusual too. Nearly every swimmer drives the legs down hard as they enter and initiates the first up-kick from well below the bodyline. Dressel holds his legs straight with toes pointed through the entry — what one coach called a check swing — and starts his first propulsion after a short glide with an up-kick, not a down-kick.

That up-kick is the real weapon. Most swimmers have a strong down-kick and a passive, weak up-kick. Dressel generates power in both directions. His coach has said that didn't happen by accident — he spent years building the up-kick with slow, perfect kicks in practice, deliberately strengthening the phase almost everyone neglects. In the Granada analysis he covered 12.9 meters underwater off the start on six dolphin kicks, and 11.2 meters off the turn on six or seven.

The Breakout: The One Rule Almost Everyone Breaks

The breakout is where most freestylers give their underwater speed straight back, and the research on why is unusually clear.

Dolphin kicking is faster than flutter kicking — about 1.41 meters per second versus 1.21 in one comparison. But the habit most swimmers carry is to dolphin kick underwater, then switch to flutter kick to "swim up" to the surface. A 2020 study measured the two strategies to the 15-meter mark: dolphin kicking straight into the first stroke averaged 1.888 meters per second, while dolphin-then-flutter averaged 1.575. Tacking flutter kick onto the end of the underwater produces a sharp deceleration at exactly the moment the swimmer is trying to carry speed to the surface.

Dressel never switches. He links his final dolphin kicks directly into his first two arm strokes, dolphin kicking through the entire first stroke cycle — a technique the Granada researchers compared to Michael Phelps's breakout. The timing is specific: he initiates the first freestyle pull on the final dolphin up-kick, not the down-kick, so the kick's propulsion and the pull's propulsion stack together rather than fighting.

That last big kick does one more job. It drives the body up into the high, downhill head position that sprint freestyle rides on. So the breakout doesn't just preserve speed — it delivers Dressel to the surface already in the exact posture he wants to sprint from.

The Same Skills, Mid-Race

The turn is where all three come together again, and the Gwangju numbers show it. From 45 to 65 meters — into the wall, the flip, the push-off, the underwater, the breakout — Dressel took 9.24 seconds. The other two medalists averaged 9.36. The rest of the field averaged 9.50.

A start happens once. A turn happens every length. A swimmer who can reproduce the underwater and breakout off a wall, under fatigue, mid-race, has an advantage that compounds with every lap.

For the record, the finish was the part Dressel was hardest on himself about. Breaking down his Olympic gold in Tokyo two years later, he pointed out an extra stroke into the wall, a breath on the last stroke, and his head left on the side too long. Even a swimmer whose first 15 meters were the best in history was still hunting for time at the end.

Where the Record Went

The honest coda makes the point sharper. Dressel's 46.96 has since been passed — Pan Zhanle went 46.40 in Paris, David Popovici 46.51, and Jack Alexy took the American record in 2025.

But look at the splits. Dressel went out in 22.29. Pan, on his world record, went out in 22.28. Alexy went out in 22.45. Dressel's front half — the start, the underwater, the breakout, and the swimming that followed — was as fast as or faster than everyone who has passed him since. The event moved past him on the back 50, not on the walls.

His first 15 meters are still the model.

What This Means for Your Own Racing

None of this depends on Dressel's physical gifts. It depends on what he chose to train, and all of it transfers to a club swimmer.

Stop obsessing over reaction time. A back-loaded, explosive start beats a twitchy front-loaded one. Power through the entry is worth more than hundredths at the beep.

Hold your line before you kick. If you start dolphin kicking the instant you enter, you're trading a perfect bodyline for propulsion you don't need yet. Let the dive carry you.

Build the up-kick. Slow, perfect dolphin kicks that generate power in both directions. Unglamorous, and it's the foundation of the best underwater in the world.

Never flutter to the surface. Dolphin kick straight into your first stroke, and time that last up-kick with the first pull.

Treat every turn as a start. The underwater and breakout off the wall are the same skills, and they pay out every single length.

Starts, underwaters, and breakouts are what swimmers practice least and could improve most. Caeleb Dressel built a career on them. At Swim With Milo, they're exactly what we film, break down, and rebuild. Reach out and let's get to work.