If you’ve ever tried to make the biggest splash at a pool party, you might think it’s all about jumping high and landing hard. But a new scientific study reveals there’s a lot more to the art of splash-making-especially when it comes to the legendary Manu jump, a beloved tradition in New Zealand’s Māori culture.
What is Manu Jumping?
Manu jumping is a water-diving style that’s all about creating the largest, loudest splash possible. Unlike Olympic diving, where athletes aim for a clean, quiet entry, Manu jumpers want to “pop a Manu”-that is, make the water explode skyward in a spectacular Worthington jet. This tradition is so popular that there’s even a Z Manu World Championship, where participants are judged on the size of their splash.
The Science Behind the Splash
Researchers from the Georgia Institute of Technology decided to get to the bottom of what makes a Manu jump so splash-tacular. They watched dozens of YouTube videos, analyzed the jumpers’ movements, and even built a robot called Manubot to mimic the action.
Their findings? The perfect Manu splash is a carefully choreographed dance between physics and body movement.
Step 1: The V-Shape Entry
The first secret is how you hit the water. Manu jumpers enter the water in a dramatic V-shape-think of sitting in an invisible chair, with your back straight and legs out in front. This pose isn’t just for style points. Entering at a 45-degree V-angle creates a large air cavity under the water, which is crucial for a big splash.
Step 2: The Underwater Rollback and Kick
Once underwater, the real magic happens. Instead of staying curled up, Manu jumpers quickly roll backward and kick their legs out, stretching their bodies straight. This move expands the air cavity even further and delays its collapse. When the cavity finally pinches off, it sends a jet of water shooting upward-the Worthington splash.
Step 3: Timing is Everything
The researchers discovered that timing the body’s opening is critical. If you open up too soon or too late, the splash won’t reach its full potential. For a jumper of average height, the sweet spot is to open the body about 0.26 to 0.3 seconds after hitting the water[6]. The Manubot robot confirmed this, showing that the strongest, tallest splashes happen when the timing is just right.
Why Does This Work?
The science behind the Manu jump is all about fluid dynamics. When you enter the water in a V-shape, you create an air cavity. By expanding your body underwater, you make this cavity bigger and delay its collapse. When gravity finally wins and the cavity closes, all that trapped energy pushes water upward in a dramatic jet.
The researchers measured the forces involved using terms like the Froude number and Bond number, but the bottom line is simple: the bigger and deeper the air cavity, the bigger the splash.
More Than Just Fun
While Manu jumping is a playful sport, the science behind it has real-world applications. Understanding how bodies (or objects) enter water and create splashes can help engineers design better ships, seaplanes, and even robots that move through water efficiently.
So, How Do You Pop the Perfect Manu?
Here’s the recipe, straight from the scientists:
– Jump from a safe height (not too high-injuries are no joke!)
– Enter the water in a tight 45-degree V-shape
– As soon as you’re underwater, roll backward and kick out to stretch your body
– Time your body opening to about a quarter-second after entry
– Watch the water rocket skyward-and your friends scatter from the splash zone!
Next time you’re at the pool, remember: making a massive splash isn’t just luck-it’s science. And with the right moves, you can pop a Manu worthy of a champion.
