phys lab quiz 5

What is neuromuscular fatigue and what causes it? How does this compare to muscle fatigue during normal physiological activities?

decreased rate of AcH release.

compares to muscle fatigue because you cannot voluntarily stimulate the muscle that fast for long enough.

What two proteins are muscles primarily composed of and are involved in The Sliding Filament Mechanism/Cross-Bridge Cycling?

actin and myosin

What is a motor unit? What is motor unit summation and when are more/less motor units recruited to produce more/less force?

a motor neuron and all the muscle cells it innervates. recruitment of more and more motor units

What is the difference between concentric, eccentric, dynamic, and isometric/static actions?

concentric: shortening

eccentric: lengthening

dynamic: both concentric and eccentric

isometric: static

What angle has the best leverage versus worst? What is a "sticking point"?

best: 90

worst: above or below 90

sticking point: point in the range of motion where a subject has the poorest leverage

What is the difference between raw EMG, iEMG, and delta T?

raw: measuring the (action potentials) of the skeletal muscle cells

iEMG: integrated EMG

delta T: the measure over the same amount of time