Nervous System
What are the two anatomical divisions of the nervous system?
Central Nervous System and Peripheral Nervous System
What are the two contractile proteins?
Actin and Myosin
What is muscle fatigue?
Decrease in force generation and shortening velocity over time.
What are the sources for ATP for muscular contractions
PC, Glycolysis, Oxidative Phosphorylation
What are 3 types of muscle actions?
Concentric, Eccentric, Isometric
What are the two divisions of the autonomic nervous system and what are their functions?
Sympathetic Nervous System - Fight/Flight
Parasympathetic - Rest/Digest
Where is calcium released from and stored?
How does high intensity exercise cause muscle fatigue?
Accumulation of lactate, H+ ADP, Pi, free radicals
(diminishes cross bridge formation)
What is the muscle fiber spit in normal people? Can you change this?
About 50/50, yes through training
Describe how the muscle length changes in concentric, eccentric and Isometric contractions.
Concentric - Shorten
Eccentric - Lengthen
Isometric - No change
What is the purpose of muscle chemoreceptors?
Provide CNS with information about metabolic rate of muscular activity. Sensitive to changes to H+ and CO2
What is the purpose of transverse tubules?
To send the action potential and regulate calcium
How does long duration exercise cause muscle fatigue?
Accumulation of Free Radials, Electrolyte imbalance, glycogen depletion
How can skeletal muscle fibers be typed?
Staining for type of myosin ATPase isoform
Why is speed of shortening fasters in fast fibers?
SR releases Calcium at faster rate, Higher ATPase activity
What are proprioceptors?
Receptors that provide CNS with information about body position
Located in joints and muscles
Where does calcium bind to?
Troponin
What is a muscle cramp?
Involuntary muscle contraction
What can impact muscle function?
Aging (sarcopenia)
other diseases (diabetes, cancer)
Describe the force velocity relations ship
Force and velocity are inversely related
What is a motor unit and what is the size principle.
A motor unit is the motor neuron and all the muscle fibers that it innervates. The size principe is defined as the progressive recruitment of motor units beginning with the smallest and progressing to larger and larger.
What are ALL types of muscle fibers
Type 1
Type 2A
Type 2X
Type 2B
What can help with muscle cramps?
Activation of ion channels in the mouth/throat can send inhibitory signals to the spinal card to inhiit over-active motor neurons and prevent camping
What are the 3 main types of biochemical properties of muscles
Oxidative Capacity (# of capillaries, mitochondria, myoglobin
Type of myosin ATPase isoform (how fast it can break down ATP)
Abundance of contractile protein (actin and myosin)
Describe force tension relation ship
There is an optimal length of muscle where the most cross bridges are formed