IB Syllabus focus: 'Levers inside the body create movement and can project objects or use implements. External levers can enhance movement functionality or improve performance in physical activity.'
Internal and external levers help explain how athletes move, project objects, and use equipment effectively. Studying both shows why technique, timing, and implement choice strongly influence sporting performance.
Internal levers in sport
An internal lever is created by the body itself.
Labeled anatomical examples of 1st-, 2nd-, and 3rd-class levers in the human body, showing how the fulcrum (joint), effort (muscle force), and load (resistance) are arranged. This helps connect the abstract lever classes to real sporting movements where different joints and muscle insertions change mechanical advantage. Source
Bones act as rigid bars, joints act as pivot points, and muscles provide the pulling force that produces movement.
Practice Questions
FAQ
Choking up means placing the hands farther up the handle, which effectively shortens the external lever.
This can:
improve control
make the implement easier to accelerate
help with quicker reactions against fast opponents
The trade-off is that potential end-point speed may decrease, so athletes often use this adjustment when control matters more than maximum power.
Stiffness influences how much an implement bends during movement or impact.
A stiffer implement may:
feel more direct
transfer force more quickly
provide less forgiveness on off-center contact
A more flexible implement may help some athletes produce smoother timing or a different feel at impact. The best choice depends on skill level, technique, and the sport’s demands.
Junior athletes usually have less strength, smaller body size, and less developed coordination than adults.
Shorter or lighter external levers can:
make technique easier to learn
reduce fatigue
improve control and safety
allow more successful contact with the ball or object
This helps skill development because the athlete can practice the correct movement pattern before progressing to larger equipment.
Yes. External levers interact with the athlete’s body size, strength, timing, and skill level.
For example:
a stronger athlete may control a heavier implement well
a less experienced athlete may lose speed or accuracy with that same implement
an athlete with faster hands may prefer a shorter lever for control
So the “best” external lever is individual, not universal.
Rules often limit implement length, weight, shape, or materials to keep competition fair and safe.
These rules help prevent:
excessive mechanical advantage
unsafe striking speeds
equipment designs that change the nature of the sport
As a result, athletes must optimize performance within set equipment regulations rather than simply choosing the largest or fastest-looking implement.
