How Can External Levers (Like a Pole Vault Pole) Affect Performance?

External levers can improve performance by increasing reach, changing torque, and producing greater linear velocity at the end of the lever. However, longer levers usually require greater force and more precise technique, so they do not automatically improve performance.

An external lever is equipment outside the body that rotates around an axis or pivot. Examples include a pole vault pole, tennis racket, golf club, bat, paddle, or hockey stick. Its effect depends mainly on lever length, applied force, and the distance between the force and the axis.

Torque is the turning effect of a force:

$$\tau = Fd_{\perp}$$

where $F$ is force and $d_{\perp}$ is the perpendicular distance from the axis to the force's line of action. Increasing this distance can increase torque if the athlete maintains the same force.

A longer external lever can also increase the linear velocity of its endpoint:

$$v = \omega r$$

where $\omega$ is angular velocity and $r$ is the distance from the axis. This helps explain why long rackets or clubs can generate high endpoint speeds. However, their greater moment of inertia makes them harder to accelerate and control.

In pole vaulting, the planted pole rotates about the box while bending. The athlete's kinetic energy is partly transferred into elastic potential energy in the pole, then returned as the pole straightens and helps raise the athlete's centre of mass. The pole is therefore not simply a rigid lever; its flexibility and energy transfer are central to performance.

Exam technique: Link lever length to torque or endpoint velocity using an equation, then explain the trade-off in force, control, or timing. Avoid the misconception that a longer lever always improves performance.