This document discusses the physiological effects of high altitude and strenuous activity on the respiratory and circulatory systems. It explains that at altitude, lung ventilation and maximum oxygen uptake increase due to improvements in cardiac output, red blood cell count, and muscle oxygen extraction. It also describes acute mountain sickness symptoms and more severe conditions like high altitude cerebral edema and pulmonary edema. Treatments focus on descending to lower altitudes, supplemental oxygen, medications, and fluid intake. The document notes that women may be better adapted to cope with oxygen lack at altitude compared to men.

1. STRENUOUS ACTIVITY, ALTITUDE AND ALTITUDE
SICKNESS

2. When he is climbing the mountain:

3. RESPIRATORY SYSTEM
INCREASED LUNG VENTILATION
 Aerobic training results in a more efficient and
improved lung ventilation.
 Lung ventilation is increased because of increased
tidal volume and respiratory frequency.

4. RESPIRATORY SYSTEM
INCREASED MAXIMUM OXYGEN UPTAKE
 Maximum oxygen uptake is improved as a result of aerobic
training – it can be improved between 5 to 30 %.
 Improvements are a result of:
- Increases in cardiac output
- Increase number of red blood cells
- Oxygen uptake difference
- Muscle capillarisation
- Greater oxygen extraction by muscles

5. RESPIRATORY SYSTEM
INCREASED ANAEROBIC OR LACTATE
THRESHOLD
 Lactate threshold changes as a result of endurance
training.
 As a result of improved oxygen delivery & utilization, a
higher lactate threshold (the point where oxygen
supply cannot keep up with oxygen demand) is
developed.

6. RESPIRATORY SYSTEM
Changes during Exercise
-Blood flow/min is increased from 5L/min to about 2530L/min.
-The total amount of oxygen entering the lungs
increases from 250ml/min at rest to about
4000ml/min.
-Carbon dioxide removal increases from 200ml/min to
about 8000ml/min.

7. CIRCULATORY SYSTEM
 Heart rate increase
 Stroke volume increase
 Cardiac output increase
 Blood flow-blood are shunted away from major organs
such as kidney, liver, stomach, intestine
 Blood pressure increase
 The difference in oxygen content of arterial and venous
blood increase

8. When he reached the highest peak:

10. RESPIRATORY SYSTEM
 Size of lungs increase to facilitate the osmosis of oxygen
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and carbon dioxide.
Increase in the vascular network of muscles which
enhances the transfer of gases.
Increase in breathing and heart rate.
Pulse rate and blood pressure increase as our hearts pump
harder to get more oxygen to the cells.
Change in oxygen affinity of blood.
The rate of miscarriages is usually higher at altitudes above
two miles because fetuses receive less oxygen from their
mothers.

11. CIRCULATORY SYSTEM
 The circulatory system cannot work as efficiently,
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because there is less oxygen and carbon dioxide
Heart rate increase
Dilation of coronary arteries
Cardiac contractility increase
After being at a high altitude for a long time, the body
will adapt.
It will produce more red blood cells so that it can pick
up more oxygen, since less oxygen is carried by each
haemoglobin at high altitudes.

13. ACUTE MOUNTAIN SICKNESS
(AMS)
 AMS usually occurs above 8,000 ft. (2,400 m)
 It is caused by reduced air pressure and lower oxygen
levels at high altitudes.
 The symptoms of AMS are sleeping
difficulty, dizziness, fatigue, headache, loss of
appetite, nausea or vomiting, rapid pulse (heart rate)
and shortness of breath with exertion.

14. TREATMENTS FOR ALTITUDE
SICKNESS (AMS)
 Descend to lower altitude or stay at current altitude to
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see if his or her body adjusts
Give aspirin or ibuprofen (Advil, Motrin) for headache
Give oxygen, if available
Avoid narcotics/smoking
Keep the person warm and have him or her rest
Give plenty of liquids (but not alcohol)

15. HIGH ALTITUDE CEREBRAL EDEMA
(HACE)
 HACE has occurred from 10,000 ft. and above.
 It occurs when AMS is overlooked and thus brain
swelling increases.
 In extreme cases, death can result.
 The symptoms of HACE are imbalance, severe
headache, vomiting, nausea, and hallucinations.

16. HIGH ALTITUDE PULMONARY
EDEMA (HAPE)
 HAPE has occurred from 8,000 ft. and above
 It occurs when excessive blood pressure causes fluid to leak
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from the blood vessels into the alveoli sacs of the lungs.
The body compensates by increasing heart rate and blood
pressure, thereby forcing more fluid into the lungs.
The fluid in the lungs blocks the oxygen-blood interface.
If altitude is not decreased, the victim drowns because no
oxygen reaches the lung/capillary interface.
The symptoms of HAPE are difficulty in
breathing, gurgling sound in lungs, fever, coughing, and
exhaustion

17. TREATMENTS FOR ALTITUDE
SICKNESS (HACE AND HAPE)
 Descend to a lower altitude as soon as possible. Even a
1,000-2,000 feet (305-610 m) descent can dramatically
improve one's symptoms.
 Oxygen therapy . If available, the patient can be placed in a
Gamow bag, which is a portable high-pressure bag that
increases oxygen tension and may stabilize the patient.
 Use of medications such as:
-Dexamethasone (steroid) that reduces swelling of
the brain.
-Diamox that signals the brain to breathe more by
correcting the imbalance chemical in the blood.
-Nifedipine that decreases the narrowing of the
artery that supplies blood to the lungs and help to
reduce chest tightness.

18. Gamow bag

19. MEN VS WOMEN
 Professor Damian Bailey, from the University of
Glamorgan, who will lead the research, believes female
brains are better equipped to deal with a lack of oxygen.
 The decrement of maximum aerobic capacity at 4350m was
less in women than in men under similar modes of ascent.
 Men are at greater risk of altitude sickness than women, as
men tend to get HAPE more frequently than women
 Normal dietary iron intakes are adequate to support
increased hemoglobin synthesis for males at high altitude,
but females exposed to high altitude may benefit from a
dietary iron supplement.