How do levers in the body let muscles move loads, and which lever is which?
Lever systems used in physical activity and sport: the components of a lever (fulcrum, effort and load), the three classes of lever (first, second and third class) with examples from the body, mechanical advantage, and the range of movement and speed each lever produces.
A focused answer to Eduqas GCSE PE Component 1 on lever systems: the fulcrum, effort and load, the three classes of lever with body examples, how to identify a lever class, mechanical advantage (with a calculation), and the trade-off between force, speed and range of movement.
Reviewed by: AI editorial process; not yet individually human-reviewed
Have a quick question? Jump to the Q&A page
Jump to a section
What this dot point is asking
Eduqas wants you to name the three parts of a lever, classify the three lever types, give a body example of each, explain and calculate mechanical advantage, and link each lever to the range of movement and speed it produces.
The components of a lever
The class of a lever depends on which of these three parts sits in the middle, between the other two. Learn the order for each class and a clear body example, because Eduqas commonly gives you a movement and asks for the class.
The three classes of lever
A reliable way to remember which part is in the middle is the mnemonic 1-2-3 F-L-E: in a first-class lever the Fulcrum is in the middle, in a second-class lever the Load is in the middle, and in a third-class lever the Effort is in the middle.
Mechanical advantage
The body trades force for speed. A second-class lever (calf raise) has a long effort arm, so a relatively small muscle force can raise the whole body weight, but the load moves only a short distance. A third-class lever (biceps curl, throwing, kicking) has a short effort arm, so the muscle must work hard, but the end of the lever (the hand or foot) moves a long way and fast. That is why third-class levers are good for generating speed in throwing and striking.
Range of movement and speed
The lever class explains the technique a performer uses. A discus thrower extends the throwing arm fully to lengthen the third-class lever at the elbow and shoulder, increasing the speed of the hand and therefore the speed the discus is released. A high jumper uses the second-class lever of the ankle to drive the whole body upward with a powerful but short plantar flexion. Knowing the lever tells you whether a movement is built for force (second class) or for speed and range (third class), which is useful when you analyse a performance for the non-exam assessment.
Exam-style practice questions
Practice questions written in the style of WJEC Eduqas exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
Eduqas 20193 marksWhen a performer rises onto the balls of their feet during plantar flexion at the ankle, identify the class of lever and label the positions of the fulcrum, effort and load.Show worked answer →
A Component 1 lever-identification item. Award marks for the class and for the correct order of the three components.
The ankle in plantar flexion (a calf raise) is a second-class lever. The fulcrum is at the ball of the foot (the toes), the load (body weight) acts through the ankle joint in the middle, and the effort is at the heel where the gastrocnemius pulls up through the Achilles tendon. So the order along the lever is fulcrum, load, effort, with the load between the fulcrum and the effort.
Markers reward "second class" plus a correct statement that the load is between the fulcrum and the effort. A labelled diagram in the right order also scores.
Eduqas 20224 marksA second-class lever has an effort arm of 0.30 metres and a load arm of 0.10 metres. Calculate the mechanical advantage and explain what this tells you about the lever.Show worked answer →
A calculation item. Award marks for the formula, the value and the interpretation.
Mechanical advantage is the effort arm divided by the load arm: .
A mechanical advantage greater than 1 means the effort arm is longer than the load arm, so a small effort can move a large load. The trade-off is that the effort end must move through a larger distance and the load moves slowly. Markers want the formula, the value 3, and a sentence saying a large load can be moved with a smaller effort.
Related dot points
- The planes of movement (sagittal, frontal and transverse) and the axes of rotation (transverse, sagittal and longitudinal), how each plane pairs with an axis, and the analysis of sporting movements such as somersaults, cartwheels and twists using planes and axes.
A focused answer to Eduqas GCSE PE Component 1 on planes and axes of movement: the three planes (sagittal, frontal, transverse), the three axes (transverse, sagittal, longitudinal), how each plane pairs with its axis, and how to analyse somersaults, cartwheels and twists.
- The types of movement possible at joints used in physical activity: flexion and extension, abduction and adduction, rotation, circumduction, plantar flexion and dorsiflexion, the joint type that allows each, and the antagonistic muscle action that produces the movement.
A focused answer to Eduqas GCSE PE Component 1 on the types of movement at joints: flexion and extension, abduction and adduction, rotation and circumduction, plantar flexion and dorsiflexion, the joints that allow each, and the antagonistic muscle pairs that produce them.
- The structure and function of the musculo-skeletal system: the major bones, the functions of the skeleton, the types of joint and synovial joint structure, the major muscles and antagonistic muscle pairs, and the types of muscle contraction.
A focused answer to Eduqas GCSE PE Component 1 on the musculo-skeletal system: the functions of the skeleton, the major bones and muscles, the structure of a synovial joint, joint types and the movements they allow, antagonistic muscle pairs, and isotonic and isometric contraction.
- The short-term (immediate) effects of exercise on the musculo-skeletal, cardiovascular and respiratory systems, and the long-term effects (training adaptations) of regular exercise on the same systems.
A focused answer to Eduqas GCSE PE Component 1 on the effects of exercise: the short-term responses of the muscular, cardiovascular and respiratory systems to a single session, and the long-term adaptations such as cardiac hypertrophy, muscle hypertrophy and a lower resting heart rate.
- The components of fitness (cardiovascular endurance, muscular endurance, strength, flexibility, speed, power, agility, balance, coordination and reaction time), how each is defined, and how they are applied to different sporting activities.
A focused answer to Eduqas GCSE PE Component 1 on the components of fitness: the definitions of cardiovascular endurance, muscular endurance, strength, flexibility, speed, power, agility, balance, coordination and reaction time, and how each is applied to a named sport.
Sources & how we know this
- Eduqas GCSE (9-1) Physical Education C550QS specification — Eduqas (2016)