Systems of the body
What neurotransmitter is released by the motor neuron to cause the muscle fiber to produce an action potential
acetylcholine
which of the following muscle fiber types has the GREATEST potential to, when trained in a specific way, CHANGE into a more aerobic or oxidative form?
a. IIa
b. IIx
c. IIc
IIa
T/F Myofiber hyperplasia refers to muscular enlargement from an increase in the cross-sectional area of the existing fibers.
F: this is hypertrophy. Hyperplasia is an increase in the number of muscle fibers via longitudinal fiber splitting.
The amount of blood ejected from the left ventricle during each beat is called
Stroke volume
Which muscle fiber is the MOST beneficial for a marathon runner
Type I
A 50 year-old female triathlete is concerned about osteoporosis. which of the following exercises is the MOST beneficial for improving her bone mineral density?
a. front squat
b. leg extension
c. bench press
d. lat pulldown
a. front squat
Motor cortex activity increases,
earlier recruitment of higher-threshold MUs
increasing firing rates of recruited MUs
reduced inhibition at the cortex and GTO
increased stretch reflex of the muscle spindle
Which of the following is an early adaptations to acclimatizing to high altitude?
A. decrease tidal volume
B. decrease respiration rate
C. increased resting cardiac output
D. increased stroke volume
C. increased resting cardia output
When throwing a baseball, an athletes's arm is rapidly stretched just prior to throwing the ball. which structure detects and responds to that stretch by reflexively increasing muscle activity?
muscle spindle
Peak power output can be increased by training with what range of load for the upper and lower body?
30-60% or by increasing the upper and lower ends of the force velocity curve.
What are the components of mechanical load that stimulate bone growth
intensity (magnitude)
Rate (speed) of loading
direction of the forces
volume of loading (number of repetitions)
During what kind of exercise intensity, does lactate not accumulate due to oxygen demand being met?
low- to moderate-intensity
What theory states that the actin filaments at each end of the sarcomere slide inward on myosin filaments, pulling the Z-lines toward the center of the sarcomere and thus shortening the muscle fiber
Sliding-filament theory
What is the benefit of increasing pennation angle in the muscle?
Increasing force production due to packing more muscle fibers in the muscle.
to increased maximal strength what load should you use?
higher loads > 70% 1RM
List all the acute changes during aerobic exercise (7).
–Increased cardiac output
–Increased stroke volume
–Increased heart rate
–Increased oxygen uptake
–Increased systolic blood pressure
–Increased blood flow to active muscles
–Decreased diastolic blood pressure
how do we modulate force when it comes to motor unit?
recruitment and rate coding
the INITIAL decrease in muscular strength after DETRAINING is due to undesired changes in which of the following systems?
nervous
What type of anaerobic exercise may help with improving our Vo2 max?
Circuit/ HITT training
Primary training adaptations of elite aerobically trained athletes include with of the following
I. increased maximal oxygen uptake
II decreased blood lactate concentrations at submaximal exercise
III. increased running economy
IV. decreased capillary density
I, II, III