Exam Three Flashcards
- Define VO2max
The amount of O2 a person is able to use
b. Can it improve with training? Does it stop improving after a certain point?
- Vo2 improves with training during the first two weeks than plateau
- Endurance athletes are able to continue improve over time
What is 1 MET?
a ratio of your working metabolic rate relative to your resting metabolic rate.
A 50 kg person is exercising at 10 METs. Calculate their absolute VO2.
[(35 ml/kg/min) x 50 kg] / 1000 = 1.75 L/min
A 100 kg person is exercising at a VO2 of 4 L/min. Calculate their relative VO2.
(4 L/min x 1000) / 100 kg = 40 ml/kg/min
(4 L/min x 1000) / 100 kg = 40 ml/kg/min
Convert 40 ml/kg/min to METs
40 ml/kg/min / 3.5 ml/kg/min = 11.4 METs
What is the primary criteria for obtaining VO2max?
<250 ml/ min changed in Vo2 with increase in intensity
If the primary criteria is not obtained, what are the secondary criteria?
- Blood lactate> 8mmol/L
- RER>1.1
- HR+- 10 bpm of age predicated max
Define the Lactate Threshold
Point where lactate accumulates exponentially in the blood
What happens to the curve with training?
With training the lactate threshold curve is pushed to the right
Define Oxygen Deficit and EPOC.
i. Oxygen deficit: almost any activity has a know oxygen cost, 2-3 mins of exercise for Vo2 to catch up
- During this time anaerobic energy system makes up for this cost
- “debt” has be paid back from the aerobic energy system
ii. EPOC: Vo2 does not immediately go down after exercise, oxygen is need to replenish things used during the exercise
What happens to both as exercise intensity increases?
as exercise intensity increases both of them will increase causing for a longer EPOC to pay back the oxygen deficit
Define Exercise Economy
Increase experience leads to a decrease energy demand
Be able to identify whether a cause of fatigue is peripheral (due to local factors within the muscle) or central (related to the nervous system).
- Peripheral Fatigue
- -Decreased rate of energy delivery
- -Buildup of acidic byproducts
- -Failure of muscle fiber’s contractile mechanism
- Central fatigue
- -Alteration in neural control of the muscle
- –Neural fatigue and loos of motivation-
Define DOMS.
- Muscle pain, stiffness, aching tenderness experienced for 1-2 days
- Cause is unknown
What may cause to DOMS?
- Eccentric contractions appear to be the primary contributor
- Structural damage
- Inflammation
- Limits glycogen storage
- Exertional rhabdomyolysis
What are some treatments of DOMS?
- Don’t train too hard too soon
- ice/cold compress
- non-steroidal anti-inflammatory drug
- exercise analgesic effect
- don’t stop exercise
What may cause the left ventricle to hypertrophy?
Will hypertrophy due to intense exercise
What are the primary structures of the cardiac conduction system?
- Regulated by the autonomic nervous system
- Signal is generated by the SA node
- Travels to AV node
- To AV bundle (Bundle of HIS)
- Speeds up 6x when it gets to the Purkinje Fibers-
Where is the impulse slowed down and sped up?
Slowed down at the AV node and speed up at the Purkinje fibers
This nerve releases Acetylcholine to slow down heart rate.
- Stimulated by the vagus nerve
- Bia neurotransmitters Acetylcholine
Define Bradycardia and Tachycardia.
- Bradycardia: HR<60 beats/min
- Tachycardia: HR>60 beats/min
When the mitral valve closes, is blood immediately expelled from the left ventricle?
When the mitral valve closes the AV valve is opened and blood is ejected from the left ventricle
How much does Atrial Contraction contribute to Ventricular Volume? (more or less than half?)
Atrial contraction increase ventricular volume
Blood Flow = ∆Pressure / Resistance. If resistance goes up or down, what will be the effect on blood flow?
When resistance goes up or down it has a direct correlation to blood flow
MAP = 2/3 DBP + 1/3 SBP. Calculate MAP from a BP of 140/90.
[(2/3) * 90] + [(1/3) * 140] = 107 mmHg
What are the receptors located in the aorta and carotid arteries that detect changes in blood pressure?
Baroreceptors
What factors within muscle tissue may cause vasodilation? (Hint: check Metabolic Regulation under Intrinsic Control of Blood Flow)
Intrinsic (within the tissue) factors can cause vasodilation
How does blood return to the heart from the veins?
- Contains one-way valves to prevent backflow
- Sympathetic stimulation
- Muscle pump
- Respiratory pump
List the two primary muscles involved in inspiration.
- External intercostal muscles
- Diaphragm
According to Boyle’s Gas Law, if volume goes up or down, what will happen to pressure?
-pressure and volume are inversely correlated, as one goes up the other goes down
Define the following respiratory measures:
- Total Lung Capacity: VC+RC
- Vital Capacity: greatest amount of air that can be expired after a maximal inspiration
- Tidal Volume: the volume of air entering and leaving the lungs with each breath
- Residual Volume: air that is remaining after a maximal expiration
What % of air is oxygen?
20%
The barometric pressure on Pike’s Peak in Colorado is 442 mmHg. What is the partial pressure of oxygen on Pike’s Peak?
442mmHg * .2093 = 92.51 mmHg
Blood leaving the left ventricle contains 20 mL oxygen / 100 mL blood. Blood returning to the right atrium contains 12 mL oxygen / 100 mL blood. Calculate the (a-¯v)O2 difference
20 mL – 12 mL = 8 mL oxygen
One molecule of hemoglobin binds to how many molecules of oxygen
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