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Whether diving off docks, cannonballing into lakes or leaping off the high board, there's nothing quite like the joy of jumping into water.

Olympic divers turned this natural act into a sophisticated science, with the goal of making a splash . But another sport looks for just the opposite: the extreme maximum splash, one as high, wide and loud as possible.

Welcome to the world of "." Although not a familiar term in the United States, manu jumping is beloved throughout New Zealand. The sport originated , where popping a manu is a way of life. There, manu jumpers leap from bridges, wharves and diving platforms to make the giant splashes.

The sport is playful yet competitive. At the , you win based on the height and width of your splash. The current record: a splash (10 meters).

The concept sounds simple, but like Olympic diving, it turns out there's a science to manu jumping.

The Worthington splash

As , the way living organisms —for instance, how flamingos feed , or how insects .

So when we stumbled upon viral videos of manu jumping on and , our curiosity was triggered. We into the art of making a splash, which is now published in the journal Interface Focus.

Our research was more than just fun and games. Optimizing how bodies enter fluids—whether those bodies are human, animal or mechanical—is an indispensable branch of science. Understanding the physics of water entry has implications for , and .

We discovered that creating the perfect manu splash isn't just about jumping into the water. Instead, it's about mastering aerial maneuvers, timing underwater movements and knowing exactly how to hit the surface.

The microsecond the manu jumper hits the water is critical. Two splashes actually occur: the first, the , forms as the body breaks the surface. The next, the , is responsible for the powerful burst of water that shoots high into the air. Manu jumping is all about triggering and maximizing the Worthington splash.

So we analyzed 75 YouTube videos of manu jumps. First, we noticed the technique: jumpers land glutes first, with legs and torso scrunched up in a .

But the moment they go underwater, the divers roll back and kick out to straighten their bodies. This expands the air cavity, the space of air created in the water by the jump; then the cavity collapses, detaching itself from the body. This period of detachment is known as "pinch-off time"—when the collapse sends a jet of water shooting upward. All of this happens within a fraction of a second.

Answers from Manubot

We found that jumpers entered the water at a median V-angle of about 46 degrees. Intrigued, we recreated these movements in a lab aquarium, using 3D-printed, V-shaped projectiles to test different V-angles.

The result? A 45-degree angle produced the fastest, tallest splashes, virtually matching what we observed in the human jumpers. V-angles greater than 45 degrees increased the risk of injury from landing flat on the back. We found it interesting that the jumpers very nearly hit the optimal angle largely through what appeared to be intuition and trial and error.

Digging deeper, we then built Manubot, a robot that mimics human body movements during manu jumps. It's able to switch from a V-shape to a straight posture underwater. This is how we learned the optimal timing to maximize splash size.

For instance, for someone who's 5-foot-7 and jumping from 1 meter, opening their body within 0.26 to 0.3 seconds of hitting the water resulted in the biggest splash. Open too soon or too late, and splash size is compromised.

One caveat: Humans are far more complex than any 3D-printed projectile or a Manubot. Factors such as weight distribution, flexibility and anatomical shape add nuance that our models can't yet replicate.

For now, though, highlight a simple truth: Creating the perfect manu splash isn't the result of luck. Instead, it relies on a carefully tuned symphony of aerial and underwater maneuvers. So the next time you see someone spray everyone in the pool with a gigantic jump, remember—there's a beautiful science behind the splash.

This article is republished from under a Creative Commons license. Read the .