Biomechanics of throwing

Front

Newton’s 1st Law (Inertia)

Back

A ball stays still or in motion unless acted on by an external force. Application: The ball doesn’t move until you apply a force with your arm.

Front

Newton’s 2nd Law (F = ma)

Back

The greater the force, the greater the acceleration (mass being constant). Application: Stronger throw = greater velocity. Bigger backswing and leg drive = more force.

Front

Newton’s 3rd Law (Action–Reaction)

Back

For every action, there’s an equal and opposite reaction. Application: As you push forward with your arm, your body braces backward—core and back foot push against the ground.

Front

Balance & Stability

Back

Key Concepts: Centre of gravity (COG), base of support (BOS), line of gravity. Application: A wide stance at wind-up gives better balance; narrowing during release helps rotation.

Front

Centre of Gravity (COG)

Back

The point where your mass is balanced. Application: Shifting COG forward improves follow-through and accuracy.

Front

Base of Support (BOS)

Back

The area beneath you that supports your body. Application: Wide BOS during wind-up increases stability.

Front

Line of Gravity

Back

An imaginary vertical line through your COG. Application: Staying aligned during the throw maintains balance and control.

Front

Levers in the Throw

Back

Arm = third-class lever (effort in the middle). Application: The longer the lever (arm fully extended), the more speed at the hand.

Front

Force Summation

Back

Combining muscle movements in sequence for maximum force. Application: Legs → hips → torso → shoulder → elbow → wrist → fingers = powerful throw.

Front

Trajectory

Back

The path a projectile follows through the air. Application: The optimal angle for long throws is around 45°—too flat or steep reduces distance or accuracy.