Unit 9-10 Flashcards
(14 cards)
Define Fatigue in sports
A reversible, exercise-induced decline in performance
Outline Peripheral Fatigue:
It occurs in the muscle itself. It develops rapidly and is caused by: a lack of energy delivery (ATP), accumulation of metabolic by-products (lactic acid), failure of muscle contraction, or lack of energy storage (glycogen)
Outline central fatigue
Develops during prolonged exercise and is caused by impaired function of the central nervous system. results in: Low coordination, and increase in reaction time, bad decision making
What is high intensity exercise?
Involves a vigorous bout of intense activity that may last for less than a second, or as long as 1-2 minutes. For example: some types of interval training, plyometrics, etc. The major sources of energy are derived from anaerobic processes
What are endurance activities
Involve prolonged sessions of low-intensity activity that may last from several minutes to several hours (jogging, cycling, etc). The major sources of energy are derived from aerobic processes
Define friction
Opposing force to the motion of an object interacting with a surface
What is static friction?
Friction that exists between a stationary object and the surface on which it is resting. Once the object starts moving dynamic friction takes over Seen when: the friction to keep the racket in hand, the friction between the shoe and the ground.
What is dynamic friction?
The opposing force that comes into play when one body is moving over the surface of another body
What is the coefficient of friction?
Dimensionless scalar quantity which is the ratio of the interaction between two surfaces. The magnitude of the coefficient of friction depends on the materials in contact. The greater the interaction between the molecules of the interfacing surfaces, the greater the size of the coefficient of friction.
Explain the influence of friction on sports performance
Consider maximizing and minimizing frictional influences in order to enhance performance. For example: sports shoes (including spikes/cleats) and playing surface (grass, artificial surfaces,
wood), winter sports (skiing, ice skating),
use of a golf glove, cycling on an indoor sloping velodrome.
Define Drag
Drag is the force or forces acting to oppose the
motion of an object through a fluid medium such as air or water.
What is surface drag?
Produced by the interaction of the surface of the object and the fluid, and can be reduced by changing materials or characteristics of the surface. (For example, a swimmer uses a cap, shaves, wears tight swimsuits)
What is form drag?
Produced by the shape of the object interacting with the fluid, and can be reduced by minimizing the surface area in contact with the fluid. (For example: a swimmer uses streamline position, a cyclist uses streamline helmet)
What is wave drag?
Produced by the interaction of the object and the fluid waves, can be reduced by minimizing the number of waves in contact with the object, or avoid producing turbulence or waves. (For example: cyclists pedal behind each other, under water swimming)
