The need for acclimatization occurs among mountaineers and trekkers who trek to high-altitude regions. Acclimatization is the process whereby an individual adapts to temperature, altitude, humidity, light, salinity, and air pressure changes.
Without this, one is at risk of lowering the lung capacity, which could cause acute mountain sickness (AMS). This is caused by low air pressure and oxygen levels. The symptoms are nausea, headache, and irrational behavior, among others.
“While at high altitude, listen to your body,” says co-founder of Bohemian Adventures LLP and an ace mountaineer, Anusha Subramanian (51) from Mumbai. She advises that mountaineers or trekkers should descend to low-lying regions with the earliest symptoms of AMS.
Need for acclimatization
As one ascends high up in the mountains, the oxygen concentration in the air reduces. So, the body needs time to adjust to low air pressure and low oxygen supply, explains Dr. Maheema Atul Bhaskar, consultant, pulmonology and sleep medicine, Dr L H Hiranandani Hospital, Mumbai. She advises acclimatizing well, not ascending more than 1000-1500 feet a day, and resting for 1 or 2 days after every ascend. “At 14000 feet and above, one must rest for at least 2-3 days to get the body acclimatized,” cautions Dr Bhaskar.
“At high altitudes, ascend during the day and return to a lower altitude before sundown so that the body can gradually adapt to the change in oxygen levels. Climb High, sleep low is the golden rule to acclimatize,” recommends Subramanian.
Risks of no acclimatization
According to Subramanian, the risks of acclimatization are very individualized. Some may only have headaches, while others may also have nausea, dizziness, and fatigue. For Subramanian, the headache and not-feeling-good symptoms indicated her body had not adapted to high altitude while on the Rudugaira peak climb in Uttarakhand, 2013. She recalls, “My ill health a few days before the climb left me exhausted. So, I did not consider acclimatizing. No sooner than I developed the earliest symptoms, I decided to stay back while the team went ahead. That was a good decision to take,” recalls Subramanian.
AMS can eventually affect the lungs and the brain. Despite early signs of AMS, rapid ascending can lead to high altitude pulmonary edema (HAPE), wherein the blood vessels constrict, causing breathlessness and other respiratory issues. In extreme cases, it could cause high altitude cerebral edema (HACE), a condition marked by fluid accumulation and brain swelling, cautions Dr Bhaskar.
Another risk factor caused by lack of acclimatization in high altitude regions is visual issues such as high altitude retinopathy (HAR), marked by dilation of retinal vessels, vision issues, and hemorrhage (in extreme cases).
Difficulties with steep ascend
In another story from 2012, a young and enthusiastic mountaineer from Noida, Arjun Vajpai, attempted to climb Mt Cho Oyo, a peak in Tibet at 8000 meters above sea level. “I was 18 then, and it was my early years of mountaineering. I rushed to complete the summit regardless of the heavy winds.” Vajpai explains, “It all started with a tingling sensation in the hands, hypoxia (low oxygen levels in the body), disorientation, and nausea.” Despite these symptoms, he was ascending higher. “Gradually, my breathing was heavy; I was feeling completely out of order,” he recalls. Since then, Vajpai has done seven 8000-meter climbs in 12 years.
Acclimatization also decreases the risk of developing color vision changes at high altitudes. In Vajpai’s case, his vision turned yellow.
Despite knowing he should descend, Vajpai continued. Nature also played the villain with heavy winds that prevented him from descending. “In three days, I developed cerebral thrombosis, a brain swelling that resulted in 11 clots in my right hemisphere and paralyzed my left body.” Vajpai bounced back after about six months. However, it could be severe for others.
How to acclimatize
Acclimatizing your lungs and body for a high-altitude mountain climb is the key to preventing AMS, emphasizes Subramanian. The preps must begin a few months in advance and not overnight.
Subramanian tells Happiest Health her process before she embarks on any climb. She focuses on improving endurance and stamina. She does cardiovascular exercises (such as trail running, hiking, and cycling) and high-intensity interval training (HIIT) to improve her lung capacity.
Pre-acclimatization techniques at sea level, such as using a high-altitude mask while training, act as a simulator for breathing in high-altitude conditions by reducing the oxygen supply. Deep breathing exercises, such as pursed lip-breathing, also strengthen the respiratory muscles and improve oxygen efficiency.
Besides the physical preps, staying hydrated before and during the climb, following a diet rich in carbohydrates, getting adequate rest, and maintaining healthy sleep hygiene are crucial, explains Subramanian.
Tests to do before mountaineering
Dr. Bhaskar recommends the following tests before climbing high mountains:
- Cardiac stress test: A cardiological examination to check heart health.
- Pulmonary function test: The spirometry test assesses the capacity of the lungs to hold the air.
- Hypoxia inhalation test (HIT): A test that simulates low oxygen conditions and assesses an individual’s performance.
Those with COPD (chronic obstructive pulmonary disease), among other respiratory issues, and pregnant women, must avoid high-mountain climbs, she cautions.
Takeaways
- Acclimatizing is the key to successful climbing at high altitudes.
- Acclimatization decreases the risk of AMS, HAPE, and HACE in extreme cases.
- Listen to your body for early signs of AMS advise experts.
- Ascend during the day and return to a lower altitude before sundown so that the body can gradually adapt to the change in oxygen levels.
- Do not ascend more than 1000-1500 feet daily; rest for a day or two after every ascend to acclimatize.
