Biomechanics Revision Flashcards
Internal Forces
Forces that our muscles can produce.
Generated by the action of muscles on the skeletal system.
External Forces
External Forces are outside the body, like gravity.
Generated outside the body.
3 Good Reasons for Biomechanics
- Improve performance
- Select appropriate equipment
- Prevent injuries.
3 Types of Analysis
- Lab Testing
- Field Testing
- Competition Analysis
Lab Testing
- Simulated under Lab conditions so factors can be controlled.
- Allows equipment to be set up close to the athletes’ or his performance.
Field Testing
- Performance is analysed in training while sustaining performance in the usual setting.
- Set up according to the surroundings.
Competition Analysis
The analysis is performed while they are acting in an event during a competition.
Motion
The change of the location or direction of a body over time.
Linear Motion
A change in position from one point to another in a straight line in one dimension, the same distance, time, speed and direction.
Angular Motion
Takes place when a body moves around an axis of rotation.
3 Axis of Rotation
Transverse, Sagittal, Frontal
Transverse Plane
An anatomical plane that divides the body into superior and inferior parts. (top half and bottom half).
Example of Use:
Hip rotation in a golf swing, twisting in a discus throw, pivoting in netball, spinning in skating.
Sagittal Plane
An anatomical plane that divides the body into two halves (left and right).
Example of Use:
Sprinting, running, and backwards running or bike pedalling.
Frontal Plane
An anatomical plane that separates the body into front and back portions.
Example of Use:
Jumping jack exercises, raising and lowering arms and legs sideways, cartwheel.
General Motion
A combination of both linear and angular rotation.
Projectile Motion
The flight of a body through the air and moves along a curved path under the action of gravity only.
Linear Kinetics
Concerns the causes of linear motion.
Inertia
The ability of a body or object to remain at rest or at a constant velocity.
Mass
The quantity of matter making up a body.
Force
The push or pull that causes motion on an object.
The push or pull action that causes an increase in the velocity of an object.
Newton’s First Law of Motion (Inertia)
A body at rest (A body can be an object) will remain at rest unless acted upon by an external force.
Newton’s Second Law of Motion (Law of Acceleration)
When an object is acted on a constant force its acceleration is proportional to the force and inversely proportional to the mass.
Newton’s Third Law of Motion (Law of Action-Reaction)
To every action, there is always an equal or opposite reaction.
Applied Forces
Those are generated by the action of muscles and applied to surfaces or objects.
Classified into Isometric and Isotonic Forces.
Isometric Forces
Action forces that Don’t Involve the contraction of muscles, or change in length of muscles.
Examples:
Gripping a racket, pushing against a wall.
Isotonic Forces
When the applied force is sufficient to change the motion of an object.
Examples:
Passing a ball, Pushing off diving blocks for a swimming start.
2 types of Isotonic Forces
Maximal Forces
Submaximal Forces
Maximal Forces
Maximal contraction by the muscles produces an all-out effect. To achieve maximal force, perfect timing and technique are required.
Submaximal Forces
Graduated muscle contraction to achieve a controlled movement. The performer must be able to apply the correct amount of submaximal force to achieve optimal performance.
Reaction Forces
When any force is applied a similar force opposes it from outside the body.
2 main principles of affecting the application of force to an object
- The greater the applied force the greater acceleration in a given direction of an object.
- The greater the mass of an object, the greater the force required to move it.
Acceleration
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Mass/Weight
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