Altitude and Exercise Flashcards
how does High altitude impact exercise?
Exercising at High altitudes will cause:
- DECREASE in barometric pressure- consequences
- Adjustments to high altitude (necessary)
- Performance enhancement
Describe the relationship between the volume of gas, pressure, percentages of Oxygen and nitrogen. What happens to these values as you go to higher altitude?
The volume of gas varies INVERSELY with pressure, BUT the relative percentages of Oxygen and Nitrogen remain the SAME
- As you move to higher altitude, the percentage of O2 and Nitrogen are NOT changed, but pressure changes
- it is easy to calculate the partial pressure of O2. .
What happens to barometric and partial pressure pressure as you reside in altitude?
As you rise in altitude, barometric pressure (air pressure) DECREASES and Partial pressure Drops Dramatically
- Partial pressure of O2 (ambient oxygen) follows barometric pressure
- it is always 21% of total barometric pressure
Describe how the level of partial pressure in atmosphere (ambient O2) impacts the amount of Oxygen in lungs (PAO2)
The less O2 in the atmosphere (Ambient O2), the Less O2 in alveoli of LUNGS.
-the lower partial pressure of oxygen, the lower the PAO2 (alveoli of lungs);alveoli (air sacs of lung)
lines for ambient O2 and PAO2 are Parallel.
Why is this important to humans
As you decrease partial pressure of O2, the amount of O2 you take in lungs decrease it.
As you rise in higher altitude (different levels above sea level), the levels of PaO2, partial pressure of O2 in blood is REDUCED, then levels out.
-if no more O2 In blood, you will get lethargy, general weakness and impending collapse.
any paO2 levels lower than 50, you collapse.
What happens to PAO2 if PO2 decreases? Why is this important to humans? How is PaO2 (partial pressure of O2 in blood) affected?
As you decrease partial pressure of O2, the amount of O2 you take in lungs decrease it.
As you rise in higher altitude (different levels above sea level), the levels of PaO2, partial pressure of O2 in blood is REDUCED, then levels out.
-if no more O2 In blood, you will get lethargy, general weakness and impending collapse.
any paO2 levels lower than 50, you collapse.
How does low levels of partial pressure of O2 affect inspired O2? How this affect O2 levels in blood.
At high altitude, partial pressure of O2 inspired will decrease.
* If the amount of O2 in air is lower, the amount of O2 inspired will be LOWER.
if the amount of O2 inspired is lower, the amount of O2 moved from lungs to blood will also be lower.
at what level of altitude will one need to live with Oxygen tank?
above 18,000 ft, you cannot live without Oxygen tank.
above 12,000 ft, you have affects.
What is hypoxia? How can hypoxia occur? How does it affect partial pressure of O2 inspired, PAO2 and PaO2?
Hypoxia can occur, when you have too little oxygen in atmosphere at high altitudes
Hypoxia will cause their to be LESS O2 Inspired, partial pressure in atmosphere (PO2) DECREASED, partial pressure of O2 in alveoli of lungs (PAO2) DECREASED and Pressure of O2 in blood will Decrease as well.
Describe the pathway of hypoxia and its affects on different partial pressures? What does a decrease in partial pressure of O2 in blood lead to? What is the result of this?
Hypoxia–> decreased PIO2, –> PAO2–> PaO2–> Disruption in Homeostasis
A decrease in partial pressure of O2 leads to Disruption in homeostasis- as all cells must work at lower partial pressure of O2, which disrupts homeostasis
The disruption of homeostasis results in adjustments in cardiovascular, respiratory, endocrine systems.
What happens to partial pressure of inspired oxygen if barometric pressure is decreased?
If barometric pressure is reduced, partial pressure of inspired oxygen is also decreased.
How do you calculate PIO2 (partial pressure of Oxygen inspired air) at sea level?
Calculate PIO2 (partial pressure of inspired O2):
At sea level:
PIO2= barometric pressure- water vapor pressure) x percent of Oxygen
ex: PIO2: (baro- water vapor pressure) x 21%= 150 mmHg
what is the partial pressure of O2 in lungs?
partial pressure of O2 in the lungs: about 105 mmHg
Describe the adaptive respiratory responses
Adaptive Respiratory responses:
-if you have decreased barometric pressure, alveoli partial pressure of o2 decreases (PAO2)
-if alveoli partial pressure of O2 decreased, Arterial pressure of O2 (blood O2) decreases.
if arterial pressure decreases, that INCREASES VENTILATION (less O2 in lungs, you will breather harder (ventilate)
if you breathe harder, you are expiring More CO2
When you expire more CO2, you take away acidity and get ALKALINITY Arterial pH rises (Co2 + water–> HCO3)
-the more CO2 you breathe out, the LESS acidic your blood will be causing respiratory alkalosis
-overtime (after several days) , Hemaglobin concentration will go UP, because you got less O2.
-kidneys produces EPO that will signal bone marrow to make more red blood cells and increase Hb [ }
-When you have less O2 or more ALKaLINE, you will make 2,3 BPG, which shifts the O2-Hb curve to the RIGHT.
When this shift curves right, there will be an INCREASE in pulmonary vascular resistance, due to CONSTRICTION of lung blood vessels.
Increase in pulmonary vascular resistance, the pulmonary arterial pressure INCREASES (stressing the heart)
What molecule does kidneys produces that enhances performance?
Kidneys produce Erythropoeitin (EPO), the performance enhancing drug that some athletes use.
EPO will signals bone marrow to make more red blood cells, increasing Hb (hemoglobin)
What are the major effects of decreased alveolar Po2?
Major effects of Decreased Alveolar PO2:
1. Ventilation
2. decreased arterial blood (PaO2), and increase in pH (respiratory alkalosis) due to breathing harder
3. Pulmonary blood flow
-Increased pulmonary resistance (due to hypoxic vasoconstriction) , causing increase in pulmonary artery pressure and hypertrophy of right ventricle (you get more musculature to Right ventricle, since RV supply blood to lungs)
4. O2-Hb curve shifts RIGHT: Increase in 2,3 BPG (due to less O2 made) which shifts O2-Hb curve right,
also increase in P50 and Decreased affinity for O2.
lower affinity for O2 means O2 will be able to be released from Hb more readily.
what led to the decrease in alveolar pressure of O2?
High altitude caused a decrease in atmospheric partial pressure of O2 (P atm) which causes a Decrease in alveolar pressure (PAO2)
*Describe the changes in ventilation that occurs at high altitude
Changes in ventilation:
-HYPERVENTILATOIN (breather harder) occurs in response to Lowered Oxygen tension
-CO2 + H2O <–> H2CO3 <–> H+ + HCO3
-if CO2 in equation goes down (when blowing Out CO2), the equillibrium shifts to left and produce less H+ (causing pH to goes up)
-Acute respiratory alkalosis occurs, which reduces ventilation initially
-Body quickly Acclimatizes and Kidney secretes HCO3-(bicarbonate)
bicarbonate will try to lower pH
Why is respiratory alkalosis so dangerous?
respiratory alkalosis is very dangerous because:
person can pass out; respiratory alkalosis REDUCES respiratory drive. People cannot breathe because there is no driving force (brain tells them not to breathe).
People who get panic attacks, breathe a lot of Co2 out, which can lead to respiratory alkalosis.
*What causes respiratory alkalosis? Where is this commonly seen?
Respiratory alkalosis is caused by someone breathing out CO2 too fast
commonly seen in people who are having panic attacks and hyperventilating
What is method used for people who hyperventilate?
People who hyperventilate (while having anxiety or panic attacks) will use paper bag to breathe out CO2 in bag and breathe in some of CO2, decreasing pH and helping with respiratory drive.
*What occurs during hypoxic vasoconstriction? what happens when too much musculature on right side of heart?
Hypoxic vasoconstriction:
- vascular constriction occurs in Lung vessels due to LOWERED Oxygen tension
- INCREASED pulmonary resistance
- INCREASED pulmonary arterial pressure to maintain blood flow
- May cause hypertrophy of right heart
- this is because build up too much muscle in right side of heart allaying heart to become stiff and it gets harder for heart to beat (no compliance, which can cause cause heart failure)
What happens to ventilation at altitude ?
You Breathe MORE at Altitude
Ventilation increases at higher altitude
*what occurs in the OxyHb dissociation curve at altitude of 4300 m? How much should Hb be normally? What is a sensor used for on finger? What happens when your Hb saturation is below 90%
In the OxyHb curve:
at altitude of 4300 m, the Hb of resting subject is approximately 85% saturated
Hb should be 95-100% saturated
The sensor on your finger will sense saturation (how much of Hb is saturated with O2).
-anything below 90% saturation of Hb- will cause patients to be in the ICU.
What causes the production of 2.3 BPG?
2, 3- DIphosphoglycerate:
- with. lower partial pressure of O2 and lower pressure of O2 inspired, you get INCREASED 2,3 DPG (or 2,3 BPG)
1. Increased synthesis of 2,3 DPG by red blood cells - This shifts Oyhemoglobin curve to RIGHT
- Greater unloading of O2 to tissues.
How does OxyHb curve change and how does it affect unloading of oxygen
With Alkalosis, you shift Oxygen-HB curve to LEFT, causing LESS unloading of O2,
when you move O2-Hb curve to RIGHT, you have GREATER unloading of O2, and less binding affinity of O2 to Hb.
How does altitude affect heart rate during exercise?
-*When you exercise, your heart rate will go up at sea level and your heart rate also increases at altitude to same degree (Altitude and sea level parallel lines in relation to HR)
*with Lower partial pressure of O2, your heart rate is higher
at any point in graph, HR (heart rate is higher
Will Heart rate keep going up?
No Heart rate does NOT continue to go up, it will eventually go down.
What is cardiac output and how does it relate to heart rate and arterial pressure? How does cardiac output change in relation to exercise?
Cardiac output-amount of blood squeezed out of heart per minute
-The more physically fit you are, the higher the Cardiac output
-*Overtime (14 days), there is accilimatization: Heart rate goes up, but eventually goes down. Similarly Cardiac output goes up at altitude but comes down.
however, Arterial pressure goes Up and STAYS UP.
What happens to VO2 max when barometric pressure and partial pressure decrease?
- VO2 max (maximal O2 consumption) goes DOWN when barometric pressure decreases (at higher altitude)
- barometric pressure goes down, partial pressure O2 goes down and VO2 max goes DOWN
What happens to Power output when VO2 max decreases ?
When VO2 max goes DOWN with high altitude, Power output goes down
*what are the acclimatization adaptations that your body makes at altitude
adaptations body makes to high altitude:
EPO-
Low Oxygen Tension in blood signals kidneys to make EPO which singles bone marrow to make Red blood cells (highest amount of RBCs for 4 days) . Then EPO goes down, since amount of RBC’s go up.
As RBC’s goes up, Hematocrit goes up
What stimulates the release of EPO from kidneys?
LOW OXYGEN level in blood stimulate release of Erythropoietin from kidneys.
Describe the relationship of RBC’s and Hermatocrit. What is Hematocrit?
Hematocrit- percentage of cells to liquid in blood
-As RBC’s (red blood cells) goes up, hematocrit percent goes UP
What is Pike’s peak and how does attendance at this place affect Hb, RBC and Hematocrit levels?
What happens when one leaves Pike’s Peak?
Pike’s Peak- a training faciitly in Colorado (high altitude), that many athletes go to.
*The more number of days you stay at pike’s peak, your Hemoglobin goes UP, red blood cells goes UP, hermatocrit goes UP
When you Leave Pike’s peak, hermatocrit goes DOWN.
*Differentiate between changes in Hermatocrit levels in men and women? Why are there differences in men and women? What can be given to women to increase their hermatocrit?
As you increase the days spent at Pike’s Peak (high altitude), Hematocrit goes UP.
Women Hermatocriy goes UP SLOWER.
Hematocrit levels start lower, and go up slower because every month women have changes to their body (bleeding, menstruation).
If you give women IRON, they can INCREASE their hermatocrit
- *Male and female hermatocrits are NOT the same. Changes/adaptation to altitude are Different in male and female.
*Describe the factors involved in oxygen transport and how they change due to high altitude
Oxygen transport:
you get increase in ventilation, increase in Hb, and Increase in Cardiac output (as Stroke volume, Heart rate and Blood pressure all increase).
Stroke volume (amount of blood pumped out in one stroke/1 beat). Stroke volume increases because SV X HR= CO.
-Greater muscular blood flow, greater capillary density because you have more capillaries overtime. Capillary density increases so that more blood reaches working muscle. You also have Greater O2 extraction, as you will have more O2 delivery to tissues.
*build up in greater muscle mass and Greater mitochondria.
*Explain how long it takes to see maximal Changs in ventilation, Heart rate, Hb [ ], capillary density, Aerobic enzyme activity, mitochondria density, and erythropoiesis
To see maximal change;
- Increased Ventilation at altitude - Weeks
- Increased heart rate at altitude - Weeks
- Increased Hb concentration- Weeks
- *Increased Capillary Density- Months/years
- *Increased Aerobic Enzyme Activity in Muscle- Months
- *increased Mitochondrial Density in Skeletal muscle- Months
- Increased Erythropoiesis- Weeks
What is the major benefit of training at Altitude (to improve sea level importance) ?
Benefit of training at altitude:
- Greater Muscle mass
- Greater mitochondrial density
- Greater O2 delivery to tissues
- Greater O2 carriage (greater Hb)
What are the 3 different ways of training at altitude? What is the other method of training ruled out and why?>
3 different ways of training at altitude:
1. Train High, Live high
2. train High and Live Low,
3. Train low, and Live High
the additional method of training is to train low and live low, but it is RULED OUT because you are not using altitude.
What is the effect of altitude on training intensity for athletes?
Effect of altitude on training intensity:
The intensity of workout DECREASES at higher altitude
As you rise in at high altitude, the VO2 max DECREASES, and the amount of exercise you can do Decreases
Describe experiment of testing effects of training at high altitudes
What are the results of the experiment
Experiment: Maximal oxygen uptakes of 2 groups were measured during training for 3 weeks at altitude and 3 weeks at sea level
group 1: trained first at sea level, and then continued training for 3 weeks at altitude
group 2: trained first at altitude, and then at sea level
*group of people work out in high altitude, and exercise intensity decreases,
*group 2 who initially starts training at altitude will have Vo2 levels go Down and Stay down, until they return back to sea level.
*group 1 starts at sea level and then goes to training at altitude, where intensity will be lowered, Vo2 lowered.
*Results of experiment:
Showed that High altitude training had DELETORIOUS results on performance times on return to sea level competition. With the groups of people, the times worsened, were even slower than they were without altitude change.
This is ex: Train High and Live High.
*What are possible negative effects on training at high altitude?
possible negative effects
- maximum cardiac output DECREASE
- Maximum stroke volume DECREASE
- Reduced maximum Heart Rate
*Describe what happens when one Lives High and Trains low and its effects on VO2 max
Live High, Train Low: INCREASES VO2 max both for males and females.
people live high and have interval training low.
after many weeks of living high and training low, VO2 Max increases when they return to sea level
VO2 Max increases for both male and females, and training time Decreases, Have better performance
What is the best training regimen for high altitude?
Best training regimen at high altitude:
Live HIGH, Train LOW
what are the prerequisites for better performance? How can rich people use to increase training adaptations.
Prerequisites for better training performance:
-The Elevation must be high enough to raise EPO (erythropoietin) concentration to Increase RBC
-Athlete must respond positively to Increased EPO
-Training must take place at an elevation Low enough to maintain training intensity and O2 consumption at near sea-level values.
you must live high enough for you to get increased RBC’s and have more O2 delivery to tissues. The difference must be big enough so when you reach low level, VO2 max (training intensity) must not be less than what it is at sea level.
if you are rich, you can live low altitude, and live in barometric chamber for certain number of hours per day, so you get used to low oxygen tension and body makes RBC’s (dangerous to live in barometric chamber) .
