Neural control
A motor neuron and all of the muscle fibers that neuron controls
Motor unit
Thin filaments are composed primarily of what?
Actin
What are three primary adaptations to endurance training
Too many things to list:
Capillary density
Mitochondrial density
Type-1 fibers
Etc.
Describe the difference between concentric and eccentric LVH. Who might have each kind?
Concentric = growing in. Eccentric = growing out. Eccentric would be found in an endurance athlete. Concentric may occur due to chronic hypertension.
Describe the size principle of motor unit recruitment
Small units recruited first, larger units recruited when necessary
Which neurotransmitter, released from the NMJ, is critical for muscle contraction?
ACh
What is the difference between hypertrophy and hyperplasia?
Hypertrophy is an increase in size, hyperplasia is an increase in the number of fibers. Hypertrophy occurs to a much greater extent than hyperplasia.
Exchange vessels
Capillaries
Describe the concept of innervation ratio
How many muscle fibers are controlled by a given neuron. Precise control vs higher force production.
Why does rigor mortis occur?
No ATP available to decouple actin and myosin. Cross bridges remain.
How does mitochondrial density compare in slow twitch vs fast twitch muscle fibers?
Higher in type-1 fibers
What does ECG/EKG stand for?
Electrocardiogram
What do muscle spindle fibers do?
Provide information about muscle fiber length and tension
Skeletal muscle is striated because of what?
Thin and thick filaments of the myofibrils give the muscle fibers the striated (light vs dark) appearance
Why does an increase in ribosomal biogenesis occur with chronic resistance training?
Ribosomes are cellular organelles that function as the primary sites of protein synthesis. More protein synthesis allows for more muscle hypertrophy
Venous pressure is approx 10% of the pressure found in the aorta. How then do we manage to move blood through the venous system?
Skeletal muscle pump and valves.
What do golgi tendon organs do?
Detect tension in the muscle, not necessarily length
Fine, tubular sheath that is lined with an uneven distribution of electrical charge
Sarcolemma
Describe the concept of cross education
Unilateral (one-sided) training has been shown to elicit strength increases on the contralateral limb
What are the four factors that effect cardiac output?
HR, contractility, preload, afterload