One of the concerns that backpackers frequently worry about is if they will get altitude sickness when they hike in the mountains. The lower air pressure and oxygen level causes some people to experience headaches, dizziness, fatigue, confusion, shortness of breath, loss of appetite, and have trouble sleeping. The faster you ascend to a high altitude, the more likely you are to develop such symptoms.
Some people are more prone to altitude sickness and can develop severe complications such as fluid on the lungs — called high altitude pulmonary edema — but that’s rare at altitudes below 10,000 feet.
One of the acclimation techniques of high-altitude hikers is once they reach an altitude of over 10,000 feet, they descend for the evening and sleep at a lower elevation. The next day, the climber goes even higher, then descends again. This works if you have a LOT of time, but most of us are only wanting to go over a high pass or climb a 14er (fourteen-thousand foot mountain) on our vacation.
Carol and I have learned that preparation is the key.
Long before leaving on a high-altitude hike we spend weeks building our cardio capacity by bicycling. We ride our tandem about 100 miles weekly and really push the speed. Our average heart rates are above 140 BPM, with efforts that reach 170 or more as we climb steep local hills. If running is your preferred activity, then make sure you add interval training to your workouts. To do intervals, first get in a good warm-up, then run at 80 percent of your maximum effort for a specific amount of time (one or two minutes). At the end of the hard effort, glide back to jogging speed until your heart rate drops to a comfortable level and repeat the process. Do this 5 or more times during your workout a couple of times each week and you will not only get faster, but your heart and lungs will become more efficient. Of course, you should always consult with a physician before embarking on any extreme exercise program.
On a recent trip to Kings Canyon, we spent the first evening in a small cabin that wasn’t far from the trailhead. Fortunately, this cabin was at an altitude of about 8,000 feet. We didn’t have any trouble walking around as we prepared for the next day’s trip, and that night we acclimated while sleeping. It is important to hydrate properly before entering the high-country. Drink plenty of water as you approach the trailhead and continue to hydrate during the entire trek.
The next day we descended to 5,000 feet and began the hike. We went up to 8,000 feet the first day. We could tell that the air was thinner than we were used to, but we didn’t have any symptoms of high-altitude sickness. Day’s two and three were spent at altitudes over 10,000 feet, and again, other than some heavy breathing, we were fine.
Always remember to sleep at high altitude your first night. Take it easy your fist day and hopefully you won’t have any altitude sickness problems.
My good friend, Net DeGalan, has climbed above 14,000 feet several times. He offers these suggestions:
- Ascend gradually, if possible. Try not to go directly from low altitude to >9,000 ft (2,750 m) sleeping altitude in 1 day.
- Once at >9,000 ft (2,750 m), move sleeping altitude no higher than 1,600 ft (500 m) per day, and plan an extra day for acclimatization every 3,300 ft (1,000 m).
- Consider using sildenafil citrate or acetazolamide to speed acclimatization, if abrupt ascent is unavoidable.
- Avoid alcohol for the first 48 hours.
- Participate in only mild exercise for the first 48 hours.
- Having a high-altitude exposure at >9,000 ft (2,750 m) for 2 nights or more, within 30 days before the trip, is very useful.
- Descend if the symptoms become worse while resting at the same altitude.
- Never ascend to sleep at a higher altitude when experiencing symptoms of altitude illness, no matter how minor they seem.