Flashcards in Muscle Performance, Injuries, and Diseases Deck (50):
Muscle performance is considered in terms of
Force and Endurance
Maximum amount of tension produced by a muscle or muscle group
Amount of time during which an individual can perform a particular activity
What factors determine the performance ability of a skeletal muscle?
Types of muscle fibers present
Physical conditioning or training
What are the three types of muscle fibers?
Slow, intermediate, fast
Describe slow fibers
Type 1 fibers
Oxidative (optimized for aerobic activity)
Describe intermediate fibers
Type 2-A fibers
Describe fast fibers
Type 2-B fibers
What is the structure of slow fibers?
Half the diameter of fast fibers
Extensive blood supply
High concentration of myoglobin
Can contract for long periods of time
What is myoglobin?
Intracellular oxygen storage molecule
True or false slow fibers are fatigue-resistant
What is the structure of fast fibers
Contain densely packed myofibrils
Large glycogen reserves
Produce rapid, powerful contractions of short duration
What is the structure of intermediate fibers?
Additional capillary supply
Smaller in diameter
Not as dependent on anaerobic metabolism
White muscles are made up of mostly
Dark muscles are made up of mostly
Training or conditioning can change what
The percentage of fast fibers that have intermediate properties
Increase in diameter of muscle
Decrease in diameter of a muscle
Increased activity leads to
Synthesis of more actin and myosin myofilaments
Decreased activity leads to
loss of actin and myosin myofilaments
Muscle fiber A is twice the diameter of muscle fiber B. Muscle fiber A can produce greater tension than muscle fiber B because
A has more myosin to actin cross bridges forming during contraction
What is anaerobic endurance
Time period in which muscular contractions are sustained by glycolysis after depleting ATP/CP reserves
What is aerobic endurance?
Time period in which muscle can continue to contract while supported by mitochondrial activities after depleting ATP/CP reserves
How do you improve anaerobic endurance?
Frequent brief, intensive workouts
Increase muscle mass
Increase glycogen reserves
Increase ability to tolerate lactic acid buildup
How do you improve aerobic endurance?
Sustained low levels of activity
Increase blood supply to muscles
Improve cardiovascular activity
When you age
Decrease muscle size, length, and endurance
Skeletal muscle becomes less elastic
The disease called tetanus caused by the bacteria clostridium tetani
Causes loss of voluntary muscle control by the nervous system
Causes strong contractions in muscles
What are primary disorders?
Disorders resulting from problems with the muscular system itself
What are examples of primary disorders?
What are secondary disorders?
Result of problems originating in other systems
What are examples of nervous system disorders?
Nervous system disorders
Define muscle spasm
Strong, sudden, unusually painful, unwanted contraction
Define muscle spasticity
excessive muscle tone
Define muscle flaccidity
very low muscle tone
Define muscle atrophy
deterioration or wasting due to disuse, immobility, or interference with normal motor neuron inneration
Tears in muscle tissue
Tears in ligament or tendon or joint capsule
Loss of voluntary motor control
What type of paralysis is the blockage of release of ACh (botulism)?
What type of paralysis is the interference with binding of ACh to receptors?
What type of paralysis is the interference with ACh Esterase activity?
What type of paralysis is the loss of motor neuron (polio)?
What type of paralysis is the loss of motor neuron axon-peripheral nerve damage
What type of paralysis is the excessive stimulation of motor neurons (tetanus)?
What are the types of inherited disorders?
What is Duchenne's MD
More common in males
Problem on X chromosome
What is Myotonic dystrophy
Chromosome 19 disorder
What are examples of minor muscle trauma?
damage to myofibrils
From excessive activity