Exam Revision Questions Flashcards
The SI unit of power is the:
Watt
A motor unit is:
an alpha motoneuron and the muscle fibres it innervates.
One way in which the CNS controls muscle force is by adjusting:
the rate at which a motor neuron fires.
- Twitch contractions are achieved at motor unit firing rates of:
a. < 10 Hz.
- Henneman’s size principle relates mainly to the concept of:
d. motor unit recruitment.
- For a normal human muscle, a maximum contraction involves the recruitment of:
d. all types of motor units.
- An example of sensory input from skeletal muscle to the spinal cord is:
c. neuronal impulses from golgi tendon organs.
- The ‘motor command’ is initiated in:
b. motor cortical regions.
- Most corticospinal neurons decussate at the:
c. base of the medulla.
- Maximum force of skeletal muscle is inversely proportional to
the velocity of muscle shortening.
- The highest muscle force can be achieved during a maximal:
d. eccentric action.
- Muscle shortening velocity is decreased in proportion to the:
a. muscle pennation angle.
- Endurance is influenced by
exercise intensity.
- Maximum power output during a single contraction is influenced by
muscle temperature.
- A normal resting value for O2 uptake in humans lies in the range of:
d. 200-400 ml/min.
- The maximum O2 uptake of a young, untrained adult lies in the range of:
c. 30-50 ml/min/kg body mass.
- Calculation of O2 uptake using the Fick equation requires the measurement of:
c. arterial [O2], venous [O2] and blood flow.
- From a haemodynamic perspective, arterial blood flow can be decreased by:
a. increasing venous pressure.
- Which one of the following variables changes the least during maximum graded exercise:
b. diastolic blood pressure.
- You measure X’s cardiac output during exercise and conclude that it has increased above its
resting value. This must mean that stroke volume has:
d. cannot determine from the information provided.
- A normal value for stroke volume at V̇ O2max is approximately:
b. 100 ml.
- Stroke volume is not directly affected by:
b. cardiac vagal activity.
- An increase in heart rate from a normal resting value to 140 bpm is caused mainly by:
c. an increase in cardiac sympathetic activity and decrease in cardiac vagal activity.
- Compared with resting values, blood flow to the skin during exercise is:
d. increased mainly by lowering vascular resistance in the skin.
- The distribution of cardiac output during exercise:
c. is characterised by a proportionately large decrease in blood flow to abdominal organs.
- Blood volume:
b. is greater in adult males than females when normalised to body mass.
- A single inspiration at rest brings approx:
b. brings approximately 500 ml of air into the alveoli.
- Breathing during exercise involves changes in
intrapleural pressure.
- During graded exercise, the volume of the anatomic dead space:
d. does not change.
- During graded exercise, the operating range of lung volume progressively:
a. increases because end-inspiratory volume increases and end-expiratory volume
- The flows of O2 and CO2 between alveolar air and pulmonary capillary blood increase during
exercise because:
b. gas partial pressure gradients increase.
- The rightward shift of the O2 dissociation curve during exercise:
c. reflects a decrease in the affinity of oxygen for haemoglobin.
- Compared with resting values, exercise changes the PO2 most in the:
c. venous blood draining skeletal muscles.
- Increased contraction force of the diaphragm during exercise is linked to an increase in:
b. thoracic volume.
- The control of breathing during exercise involves:
d. humoral influences (e.g., blood K+
levels) on peripheral chemoreceptors.
- Which of the following defines convective heat loss/gain?
c. Exchange of heat by the motion of gas or liquid across a surface.
- A maximum level of core temperature typically occurs at what time of the day for an individual
with a normal circadian rhythm?
d) 17:00-19:00
- Sweating during exercise:
c) is a more effective heat loss mechanism in dry than humid air.
- Which one of the following is not an adaptation to heat acclimation training?
c) Increased core temperature threshold for sweating.
- Which of the following variables adapts and decays first in response to repeated heat stress and its removal?
a) Plasma volume.
- At rest and across a 24-hour period, core temperature normally varies by approximately:
d. 0.5 degrees Celsius.
- During exercise, most of the energy released via fuel metabolism is converted to:
b) heat.
- The ergogenic effect of pre-cooling on ‘endurance’ events is mainly related to:
c. altered heat storage capacity.
- Signs and symptoms of heat stress after exercise include:
a. high resting heart rate, dark urine and dizziness.
- Compared with the euhydrated state, dehydration during exercise in the heat:
a. decreases skin blood flow and the rate of heat loss.
- Cerebral blood flow can decrease during exercise when:
b. ventilation rises far in excess of metabolic needs (i.e. V̇ O2).
