20
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Essentials of Strength Training and Conditioning
STUDY QUESTIONS
1. To which of the following structures do the
cross-bridges attach during muscle action?
a.
b.
c.
d.
actin
myosin
M-bridge
sarcolemma
2. Which of the following substances regulates
muscle actions?
a.
b.
c.
d.
potassium
calcium
troponin
tropomyosin
3. Which of the following substances acts at the
neuromuscular junction to excite the muscle
fibers of a motor unit?
a.
b.
c.
d.
acetylcholine
ATP
creatine phosphate
serotonin
4. Which of the following muscle fiber types is
the MOST beneficial fora marathon runner?
a.
b.
c.
d.
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••
Type
Type
Type
Type
I
IIa
IIx
lIe
5. When throwing a baseball, an athlete's arm
is rapidly stretched just prior to throwing the
ball. Which of the following structures detects
and responds to that stretch by reflexively
increasing muscle activity?
a.
b.
c.
d.
Golgi tendon organ
muscle spindle
extrafusal muscle
Pacinian corpuscle
6. From which of the following is the heart's
electrical impulse normally initiated?
a.
b.
c.
d.
AVnode
SA node
the brain
the sympathetic nervous system
7. Which of the following occurs during the QRS
complex of a typical ECG?
1.
II.
III.
IV.
depolarization
repolarization
repolarization
depolarization
of the atrium
of the atrium
of the ventricle
of the ventricle
a. I and III only
b. II and IV only
c. I, II, and III only
d. II, III, and IV only
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