Physiology of Exercise Flashcards
How many months of training would illicit the long term effects of exercise?
6-12 months
What are anticipatory responses caused by?
norepinephrine and epinephrine
Before exercise, the heart rates starts to quicken. What is shown?
anticipatory response
Give 5 acute responses to exercise.
- increased heart rate
- increased stroke volume
- increased blood pressure
- increased respiration rate
- increased temperature (red skin, sweating)
Why does heart rate and contraction strength increase during exercise?
because the muscles (in particular) need more oxygen
Which arteries are the common site for measuring heart rate?
radial (arm); carotid (neck)
What term is used to describe the amount of blood the heart can pump in one beat?
stroke volume
When sensory nerve activity from exercising muscles stimulate the respiratory muscles, what mechanism during ventilation is at play?
neurogenic mechanism
Humoral mechanism is at play during ventilation. Give examples of humoral factors that influence ventilation.
CO2, O2, H+ (affects alveolar ventilation)
By how much times can ventilation increase by during rigorous exercise?
20 fold
CO2 pressure, O2 pressure, and pH increases during exercise. T/F
F. These remain constant during exercise.
Exercise-enhanced breathing is not prompted by increases in these factors.
What are the 4 main factors that increase rate of respiration during exercise?
- anticipatory response
- impulses from proprioceptors
- increased temperature
- body temperature increases
What receptors are responsible for position and movement present around the joints, muscles, tendons, and joint ligaments?
proprioceptors
What is being described?
impulse from cerebral cortex → skeletal muscle → collateral impulses → respiratory center → increased ventilation
pathway of an anticipatory response by increasing rate of ventilation
How does exercise increase temperature?
increased metabolism increases body temperature which stimulate respiration directly and indirectly
Why does the body heat up during exercise?
repeated muscular contraction increases body’s core temperature
What is the average heart rate?
70 bpm
Perspiration can increase to how much during exercise?
1L
What is the average stroke volume at rest?
70-80 ml
Respiration rate can increase up to how much during exercise?
40-50 breaths/p min
How much is the average stroke volume?
70-80 ml
What is the average amount of tidal volume at rest?
0.5 L
What is the average amount of tidal volume during exercise?
2.5 L
What is the average cardiac output during rest?
4 - 6 L
What is the role of the muscular system in pushing blood back to the heart faster?
muscle fibers contract and squeeze the veins
Why do arteries expand during exercise?
to prevent blood pressure from going too high up
Blood does NOT move from where there is less need for it towards the areas that are working.
This is because the body (inc. organs/tissues not working) needs to be oxygenated at the same manner as a whole. T/F?
F
Why does reddening occur during exercise?
blood heats up and moves closer to the skin
The level of CO2 in the blood and ____________ in the muscles increase during exercise.
cellular respiration
Does gas exchange in the lungs speed up, slow down, or remains constant during exercise?
speeds up
Vasodilation and vasoconstriction happens as a whole during exercise. It is not localized and thus constricting at different points is not possible in the arterial system. T/F?
F
Why is progression necessary during training?
Muscles increase in strength. Overtime, the load won’t be considered as “stress” anymore
One of the short-term effects of exercise is that energy reserves (fat) starts to diminish. Why?
GI tract gets used to not getting all the energy (calories)
What are the two acute responses to exercise?
- anticipatory response
- acute neural response
What is the function of the acute neural response to exercise?
sends signals to chemicals, organs needed, and not needed for exercise.
What is the proper term for “blood conditioning organs”?
They can tolerate low levels of oxygen of blood because they remove waste.
Ischemia tolerant organs
How come ischemia tolerant organs can tolerate low levels of oxygen?
- because their metabolic needs does not come from oxygen.
- due to factors like their slower metabolism and ability to shift to anaerobic metabolism
Give 3 examples of ischemia tolerant organs
GI tract, kidney, lungs
Which one is more dominant during exercise: sympathetic or parasympathetic activity?
sympathetic
What does the increased sympathetic activity result to?
arterial constriction and decreased oxygen and blood supply
No matter how fast or deep you breath, the oxygen supply will not be adequate. What kind of metabolism does your body switch to?
anaerobic metabolism
During exercise, there will be a shift from the oxygen pathway to the non-oxygen metabolic pathway. (Aerobic → Aerobic) What is observed?
Proportional Anaerobism
What is the average cardiac output?
5L p/min
By how many times does cardiac output increase by during exercise?
5x
What are the 2 categories in which we can characterize the effects of exercise?
acute, chronic
Give 4 examples of chronic responses to exercise.
- cardiac hypertrophy
- decreased resting heart rate
- decreased body fat
- increased heart acclimatisation
Which part of the heart increases in size during heart hypertrophy?
ventricles. particularly the left ventricles.
(1.1 cm > 1.3 cm)
Why does cardiac hypertrophy occur?
due to the heart’s sustained ability to pump high levels of blood through the body. linked to increased stroke volume
Why is there a decrease in heart rate after chronic exercise?
heart becomes more efficient in pumping blood. linked to cardiac hypertrophy because the heart can now pump more blood, it doesn’t need to beat as much.
How many percent of our maximum heart rate should be done to see a decrease in body fat levels?
60-85%
How do you measure maximum heart rate?
Max heart rate = 220 - age
Aerobic activity leads to increased:
- aerobic threshold
- cardiovascular endurance
- lung capacity
anaerobic activity lead to increased:
- anaerobic threshold
- muscular endurance
- lactic acid tolerance
There is an increase of capillary network after chronic exercise? T/F?
T
Why is there an improved performance in sports after regular training?
due to an improved aerobic base (basic level of fitness)
What are the benefits of strength training?
- muscle mass and strength
- bone density
- metabolism
- overall stability and balance
Reducing your weight by just _____lbs or _____kg may be enough to lower blood pressure.
10llbs; 4kg
What are the energy systems used by our body during exercise?
- ATP-PC System
- Lactic Acid System
- Oxygen (aerobic) System
What chemical fuel reserve is utilized by the ATP-CP system?
creatine phosphate
where is creatine phosphate stored?
muscles
Is the ATP-CP system aerobic or anaerobic?
anaerobic
Briefly describe the process of the ATP-CP system.
- CP is broken down to Creatine and Phosphate
- Energy released from breakdown is used to combine ADP and Pi
- Combination produces ATP
The supply of CP is limited. It can only be used for how many seconds effectively?
10-20 seconds
After ________ months, our brains get used to low blood supply. What happens to our higher cortical function?
6 months; exhibits shunting (causes less thinking).
Why do people feel “less pain” after training for a certain period time?
body sends out dopamine which overcomes feelings of pain
Briefly describe the lactic acid system?
anaerobic breakdown of glycogen
Carbohydrates are stored in the liver and muscles as what?
glycogen
From the breakdown of glycogen, we get a
bi-product called what?
pyruvic acid
During times where oxygen is insufficient, pyruvic acid is stored as what?
lactic acid
Energy from the lactic acid system can last how many minutes?
3 minutes
Energy from the lactic acid system can only last for a certain amount of time. Why?
the buildup of lactic acid prevents further energy production
Complete the diagram:
ADP + ________ = ________+ Pyruvic Acid
glycogen; ATP
How does the aerobic system work?
via oxygen and performing a series of chemical reactions known as the “Krebs Cycle”
Oxidative Phosphorylation produces how much ATP?
36
The continued breakdown of ______ becomes pyruvic acid and enters the mitochondria when the aerobic system is used.
glycogen
Fats and proteins can only be broken down aerobically, T/F?
T