The Physics Behind the Fosbury Flop: How One Athlete Revolutionized High Jumping

Dick Fosbury, an athlete who initially struggled to compete in high jumping, revolutionized the sport with an innovative technique known as the Fosbury Flop. This method, which involves jumping backward over the bar, not only improved Fosbury's personal records but also transformed the entire landscape of high jumping. Let's delve into the physics that underpin this groundbreaking technique.

The Genesis of a Revolution

In the early 1960s, Dick Fosbury found himself unable to match the performance of his peers using conventional high jumping techniques. At 16, he experimented with a radical approach: jumping backward. Instead of facing the bar and using the traditional straddle method, he turned his back to it. This simple change yielded astonishing results.

Fosbury's record improved dramatically, leaving his coaches in awe. He honed his style over the next few years, securing a spot in the 1968 Olympics in Mexico City. There, he captivated the world, winning a gold medal and setting an Olympic record of 2.24 meters. By the subsequent Olympic Games, the Fosbury Flop had become the dominant technique, adopted by nearly all competing high jumpers.

The Physics of the Flop: Center of Mass

The secret to the Fosbury Flop lies in a fundamental physics concept: the center of mass. Every object has a center of mass, which represents the average position of all its mass. For a symmetrical object like a flat rectangle, the center of mass is at the intersection of its diagonals. For more complex shapes, it can be found through calculations or by identifying the object's balancing point.

Understanding Center of Mass

• Definition: The average position of all the mass of an object.
• Location: Can be inside or outside the object's physical boundaries.
• Movement: Shifts based on body position.

Humans also have a center of mass, typically located around the belly when standing. However, its position changes as we move. When you lift your arms, your center of mass shifts upward. Bending forward can even place your center of mass outside your body, below your belly.

Objects like doughnuts and boomerangs also have centers of mass located outside their solid form.

The Advantage of the Fosbury Flop

The brilliance of the Fosbury Flop is how it manipulates the jumper's center of mass. As the jumper approaches the bar, they convert horizontal velocity into vertical lift. The key moment occurs as their body arches backward over the bar. This arching motion lowers the jumper's center of mass, positioning it below the bar.

How It Works

1. Approach: High-speed run to generate momentum.
2. Takeoff: Conversion of horizontal velocity to vertical velocity.
3. Arch: Bending backward to lower the center of mass.

With traditional techniques, jumpers had to exert enough force to lift their center of mass a few inches above the bar to clear it. The Fosbury Flop allows the jumper to apply the same force but achieve a much higher body position. By arching the body, the jumper can clear the bar even when their center of mass remains below it.

A Great Leap Backward, A Great Leap Forward

Dick Fosbury's technique revolutionized high jumping by effectively separating the jumper's body from their center of mass. This separation provides additional clearance, enabling athletes to jump higher than ever before. The Fosbury Flop, a seemingly backward approach, represents a monumental leap forward in the world of sports.