“I run marathons, so altitude sickness shouldn’t affect me, right?”
In fact, high altitude illness will not spare you just because you exercise regularly.
Myth #1: Being Fit Prevents Altitude Sickness
Altitude sickness has nothing to do with fitness; it relates to how fast your body adapts to low oxygen.
The air oxygen content above 2,500 meters is only about 75% of sea level, and it drops to less than 55% at 5,000 meters.
Faced with such an environment, the body needs time to trigger a series of adaptation mechanisms:
| Adaptation Mechanism | Purpose |
|---|---|
| Deeper and faster breathing | Increase air intake |
| Faster heart rate | Accelerate blood circulation |
| Increased red blood cells | Improve oxygen-carrying capacity |
These adjustment speeds vary from person to person, depending on your genes and your physical state on the day, and have no direct relation to how many kilometers you usually run.
Fit people are actually more prone to make a mistake: climbing too fast.
Because their muscles do not feel tired, they ignore that other systems of the body are lacking oxygen.
Myth #2: Being Fine Last Time Means Being Fine This Time
The occurrence of altitude sickness is not constant; every climb’s conditions and physical states are different.
There are too many variables affecting altitude acclimatization:
| Variable | Influence |
|---|---|
| Ascent Speed | For the same mountain, chartered vehicle direct ascent vs. three days of slow hiking leads to completely different results |
| Sleep Quality | Insomnia the night before or staying up late the previous week will reduce adaptation capacity |
| Physical Condition | Unrecovered cold or gastrointestinal discomfort means the immune system is already consuming resources |
| Water Intake | Dehydration will worsen the symptoms of altitude sickness |
| Alcohol | Even in small amounts, it will suppress the respiratory center |
Being fine last time might just mean the conditions were all just right that time.
Every time you go up a mountain, prepare as if it were your first time.
Myth #3: Taking a Painkiller Will Fix the Headache
Painkillers only suppress the alarm; they do not disarm the danger.
When a headache occurs above 2,500 meters, the first reaction should be:
- This could be altitude sickness
- Stop ascending further
- Observe for other symptoms (nausea, dizziness, insomnia)
Taking painkillers can temporarily relieve discomfort, but if the root cause is cerebral vasodilation caused by hypoxia, painkillers will only make you falsely assume you are fine and keep climbing, leading to a sudden outbreak at higher altitudes.
The rule for handling headaches on mountains: “Unless you can prove it is due to other causes, always treat it as altitude sickness first.”
Myth #4: Inhaling Oxygen Lets You Keep Climbing
Oxygen is an emergency rescue tool, not a cure.
Using oxygen (bottled oxygen or portable hyperbaric chamber) at high altitudes is equivalent to “temporarily returning you to a lower altitude”:
| Oxygen Equipment | Effect | Limitation |
|---|---|---|
| Bottled Oxygen | Directly supplements inhaled oxygen concentration | Limited capacity, usually only lasts for a few hours |
| Portable Hyperbaric Chamber (PAC) | Simulates a drop in air pressure of 1,500 to 2,000 meters | Lasts about 1 to 2 hours per use, requires manual pressurization |
The function of both oxygen and medication is to “buy time to descend,” not “to let you keep climbing up.”
Once the oxygen supply is removed, the body returns to the same hypoxic environment. If you do not descend, symptoms will keep recurring or even worsen.
Myth #5: Walking Slowly Prevents Altitude Sickness
Ascent speed is the key factor affecting altitude sickness.
The critical indicator for altitude sickness prevention is “the net gain in sleeping altitude per day,” not your walking speed.
| Scenario | Risk |
|---|---|
| Riding a car for 3 hours directly to 3,400 meters | High risk, the body has absolutely no time to adapt |
| Hiking for 2 days from 2,000 meters to 3,400 meters | Lower risk, the body has time to adjust gradually |
| Climbing from 3,000 meters to 4,200 meters within a day, but sleeping back at 3,000 meters | Well controlled, aligns with the “climb high, sleep low” principle |
Many Baiyue itineraries, to fit holidays, are designed to go directly from the trailhead (approx. 2,000 meters) to a cabin above 3,000 meters for overnight stay in one day.
This kind of itinerary design itself is a breeding ground for altitude sickness.
If the itinerary cannot be changed, at least do the following:
Consult a travel medicine clinic before departure and carry preventive medications.
Myth #6: Only Children and the Elderly Get Altitude Sickness Easily
Age is not a deciding factor.
| Group | Actual Situation |
|---|---|
| Young Adults | The incidence is not lower than the elderly, and they are more likely to ignore symptoms due to overconfidence |
| Children | Because they cannot express discomfort accurately, they are more prone to delayed discovery |
| Women | Some studies show slightly higher AMS incidence in women, but the difference is not significant |
| Long-term High-Altitude Residents | Returning to high altitude after a stay at sea level, they can still experience altitude sickness |
Everyone is equal in the face of altitude sickness. The only difference is whether you are prepared.
Myth #7: Taking Altitude Sickness Pills Guarantees Safety
Fact: Medication is a support tool, not a magic cure.
The most common preventive medication, Diamox (Acetazolamide), works by speeding up the body’s acclimatization process, prompting your kidneys to excrete bicarbonate, which acidifies the blood and stimulates the respiratory center to deepen breathing.
But it has several major limitations:
| Limitation | Description |
|---|---|
| Not suitable for everyone | Contraindicated for people with sulfa drug allergies |
| Has side effects | Numbness in hands and feet, frequent urination, altered taste for carbonated drinks |
| Cannot replace acclimatization | Even after taking it, you still need to control the ascent speed |
| Needs to be taken in advance | Usually starts 1 day before departure, continued until 2 days after arriving at the highest altitude |
Medication is like a seatbelt; it can save lives at key moments, but it doesn’t mean you can drive with your eyes closed.
Altitude Sickness Risk Assessment for Different Routes
The following compiles the risk levels of common high-altitude routes in Taiwan and overseas:
Taiwan Baiyue
| Route | Maximum Altitude | Risk Level | Suggestion |
|---|---|---|---|
| Hehuanshan Main Peak | 3,417 meters | Moderate | Start from Cingjing, adapt midway |
| Yushan Main Peak | 3,952 meters | Moderate-High | Acclimatize before staying overnight at Paiyun Lodge (3,402 meters) |
| Jiaming Lake | 3,310 meters | Moderate | Two-day itinerary has high risk; three-day itinerary is recommended |
| Qilai Main & North Peaks | 3,560 meters | Moderate-High | High risk if ascending directly to Chenggong Cabin on day one |
Overseas Routes
| Route | Maximum Altitude | Risk Level | Suggestion |
|---|---|---|---|
| Mount Fuji, Japan | 3,776 meters | Moderate | Strongly recommended to stay overnight at the 7th or 8th station |
| Nepal EBC | 5,364 meters | High | Standard itinerary takes about 12 to 14 days, including multiple acclimatization days |
| Lhasa, Tibet | 3,650 meters | Moderate-High | Flying direct has extremely high risk; taking the train to Tibet is recommended |
| Cusco, South America | 3,400 meters | Moderate-High | Can stay in a lower-altitude city for 1 to 2 days first |
| Mount Kilimanjaro | 5,895 meters | Extremely High | Choose a route of at least 6 days or more |
What You Can Do Before Departure
| Preparation Item | Description |
|---|---|
| Travel Medicine Clinic | Inform the doctor of destination altitude, itinerary days, ascent speed, and discuss preventive meds |
| Physical Training | While it doesn’t prevent altitude sickness, good fitness can reduce extra physical burden |
| Study the Route | Understand daily altitude changes and mark potential risk zones |
| Prepare Gear | Oximeter (fingertip), headache pills, warm clothing |
| Inform Teammates | Let teammates know your physical condition and past history of altitude sickness |
The best attitude toward climbing: “Keep awe for the mountains, keep honesty to your body.”