A quick revision summary of Class 11 Physical Education Unit 8: Fundamentals of Kinesiology and Biomechanics in Sports. Read the full notes for the drawn movements, planes and axes.
1 Kinesiology
Core terms
KinesiologyGreek kinesis (movement) + logos (to study); study of human movement and muscular function; also called human kinetics
FatherAristotle (384-322 BC): first analysed walking (rotatory into translatory motion)
DefinitionsRasch & Burke 1978: Kinesin (to move) + logos (to discourse) · Burke 1977: movement behaviour of all living organisms
Draws onBiomechanics, anatomy, physiology, neuroscience; body seen as a purposeful machine
- Importance (13): analysing motion · motor skills (walking, running) · injury prevention (landing, falling, catching) · economy of movement · effectiveness (snatch) · clinical (posture) · exercise and conditioning (sit-ups) · principles of movement (bones as levers) · fundamental movements · self-realisation (basketball jump) · teaching motor skills · evaluation of exercise · physiotherapists: safety, effectiveness, efficiency.
2 Biomechanics
Core terms
BiomechanicsGreek bios (life) + mechanics; mechanics of the functional and anatomical analysis of biological systems; the central part of kinesiology. Word 1899, biomechanical 1856
Hatze 1974Movement of living things studied with the science of mechanics
James G. HayInternal and external forces acting on a human body and their effects
Sports biomechanicsPhysics of sports: how and why the body moves; modelling, simulation, measurement
MechanicsStatics (rest / constant velocity) and dynamics (acceleration) → kinematics + kinetics
- Importance (13): performance analysis (GAIT, cinematography, videography, EMG, accelerometer, dynamometry, electrogoniometry) · technical profession · motor abilities · diagnostic teaching · diagnostic coaching · self-evaluation · equipment · rules · new techniques · suitable technique (bullet start, short sprinter) · player selection (short: gymnastics, tall: volleyball) · exercise design (half-squat) · injury prevention and rehabilitation.
3 Nine Principles of Biomechanics
| Principle | Key idea | Book example |
|---|---|---|
| Force-Motion | Unbalanced forces create or modify motion; free-body diagram | Standing still: forces equal, no movement |
| Force-Time | Timing of force as important as size; Impulse = Force × Time | Sweep shot in hockey |
| Inertia | Resistance to change of motion; mass (m), moment of inertia (I) | Shot put vs netball |
| Range of Motion | Less ROM: accuracy; more ROM: speed and force | Dart vs javelin |
| Balance | Wide base, low CG, more mass; line of gravity mid-base; stability and mobility inversely related | Sumo wrestlers |
| Coordination Continuum | High force: simultaneous; low force, high speed: sequential | Weightlifting vs baseball pitcher |
| Segmental Interaction | Force transferred through linked segments; large and slow to small and fast | Golf and tennis shots |
| Optimal Projection | Optimal angle range for a goal; 45° for maximum distance | Golf ball on a level plane |
| Spin | Stabilises flight, creates lift; changes trajectory and bounce | Top spin in tennis: drops quicker |
4 Kinetics vs Kinematics
| Kinetics | Kinematics |
|---|---|
| Forces causing motion (gravity, friction, torque) | Describes motion: time, displacement, velocity, acceleration |
| The why; gets at the cause | The how; descriptive, by observation |
| Considers mass and external forces | Not dependent on mass |
| Energy transformations | Treated geometrically |
| Newton’s three laws; push or pull | Centre of mass (COM) linear + angular motion |
| Person in a train, child running in the house, running fan | Moving train, parabolic path of a football, stone hitting the ground |
5 Body Movements
| Movement | Meaning |
|---|---|
| Flexion | Bending; joint angle decreases |
| Extension | Straightening; joint angle increases |
| Abduction | Away from the centreline |
| Adduction | Towards the centreline |
| Rotation | Around the long axis |
| Circumduction | Flexion + extension + abduction + adduction; ball and socket joints (shoulder, hip) |
| Supination | Palm up |
| Pronation | Palm down |
- Movement vs locomotion: movement changes a part’s position; locomotion moves the whole organism. Human movement = muscle contraction + joint bending, controlled by the nervous system.
6 Planes and Axes
| Plane | Divides | Movement | Axis (perpendicular) | Examples |
|---|---|---|---|---|
| Sagittal (median) | Right | left | Flexion, extension | Frontal (transverse, mediolateral) | Kicking a football, walking, squatting |
| Frontal (lateral, coronal) | Front | back | Abduction, adduction | Sagittal (anteroposterior) | Jumping jack, star jump, cartwheel |
| Transverse (horizontal) | Upper | lower | Rotation | Vertical (longitudinal) | Golf swing, discus twist, skating spin |
- Terms: anterior/ventral (front), posterior/dorsal (back), superior/cranial (head), inferior/caudal (lower), medial (towards midline), lateral (away).
- Centre of gravity = point where the three planes intersect. Tri-planar motion: all functional movement is three-dimensional (the hip during walking).
7 Memory Hooks
Memory Trick
F-F-I-R-B-C-S-O-S
“Fast Feet In Race Bring Champions Success On Stage”: the nine principles in book order.
- Kinetics = tug (force, why); kinematics = measure (how).
- Supination holds the soup: palm up.
- Plane and axis names cross over: sagittal plane ↔ frontal axis; frontal plane ↔ sagittal axis; transverse plane ↔ vertical axis.
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