Getting in shape for high altitude hiking
There are few places you can wake up in your own bed, ascend 9,000 vertical feet to a mountain top and get home in time to catch the evening news. Boulder is a fantastic base for exploring Colorado’s alpine regions. Living more than a mile above sea level, we already have a lot of advantages — but that doesn’t mean that those lofty summits come easy.
We have roughly 17 percent less oxygen than we would at sea level. Our bodies compensate by increasing red blood cell production, thereby making our respiratory system more efficient.
That helps when heading to peaks over 14,000 feet (a.k.a. the 14ers), where the oxygen levels are even lower as a result of decreased atmospheric pressure.
If you haven’t been to high altitudes in a while, you will likely feel the effects of the thin air. Serious health issues, including High Altitude Cerebral Edema (HACE) and High Altitude Pulmonary Edema (HAPE) can occur as low as 6,000 feet, but for the majority of Colorado residents, should not be an issue. However, Acute Mountain Sickness (AMS) is an issue, which is why you should take steps to prepare for high altitude hikes.
Boulder is ideally set up for high altitude training, thanks to the progression of peaks in our backyard. Mount Sanitas at 6,800 feet is a great place to reintroduce your body to the rigors of hiking at elevation. The “Guardians of the Flatirons” trio of Bear Peak, Green Mountain and South Boulder Peak bring you even higher, over 8,000 feet in height with over 3,000 vertical feet gained. Most people will have no problem with the oxygen levels at these heights, even if their fitness level may leave them wheezing. Hikes on these peaks are the perfect primer for higher peaks.
If you feel good on these mountains, you should feel fine on terrain up to 12,000 feet — the average height of the high lifts at most Colorado ski areas. But there is a difference between a quick visit to the thin air and laboring away for hours at a time at altitude. The key to proper acclimatization is spending enough time at a high enough altitude to adjust.
If you can spend a night or two at 9,000-10,000 feet before heading up over 13,000 feet, you will likely notice a strong performance boost at altitude. When hiking 14ers over a weekend, I prefer to sleep a little lower if possible, around 9,500 feet, rather than struggle through a night at trailheads that are 10,500 feet. and higher. Many Coloradans have suffered through a long night when trying to rest at the high-altitude huts, many of which are over 11,000 feet.
The good news is that it often only takes 24-48 hours above 9,000 feet to feel strong on Colorado’s highest mountains. And the more time one spends at higher elevations, the better the body can adapt to repeat visits. While it’s certainly possible to ascend 14ers from Boulder in a single day, it’s worth working up a few lower peaks first to gauge how you feel. A small headache or upset stomach is normal and usually goes away as you return to lower elevations.
However, even if you’ve previously had no issues at altitude, AMS can unexpectedly hit fit, acclimated hikers. If you start to feel dizzy, nauseous and find it hard to concentrate, it’s time to head down. Resist summit fever and rest up — chances are you just needed a bit more time at altitude before striking out for the high peaks.
It is well known staying hydrated is essential to a good day in the mountains. As we climb higher, our bodies increase our rate of respiration to compensate for the lower levels of oxygen. Add to that the perspiration of grinding out a tough hike and the radiation of the sun (please remember to put on sunblock!) and your body can burn through liquids. Even during periods of high exertion, humans can only take in 16-20 ounces of water an hour, so keep this in mind as not to overhydrate and flush essentials food fuels out of your body too quickly. Making sure you are well hydrated the night before is key. Adding in electrolytes in your drink (sport drinks, tablets, etc.) will help prevent cramping.
At altitude, it’s hard to digest heavy foods. Energy gels and gummies are very easy to digest and provide a real boost (I like to take in 100- 200 calories per hour on hiking days, even during the descent). Solid bars, sandwiches and snacks work for some people, but can ultimately slow you down, as digestion is tough at altitude mostly due to a lack of red blood cells. In fact, many athletes prefer a big meal the night before and will skip an official breakfast the morning of, instead using gels and gummies throughout the day.
If you do start to feel lousy, gelbased Ibuprofen tablets can stave off an oncoming headache – as well as sore knees (Vitamin I as it is sometimes called). Antacids will help with a foul belly. While there are prescription drugs such as Diamox that can help with acclimation, they can have strong side effects and are usually not necessary for Colorado natives.
If you’d like to learn more about high altitude fitness and adaptation, there are several excellent books on the subject. Medicine for Mountaineering: And Other Wilderness Activities by the Mountaineers and Going Higher: Oxygen Man and Mountains by Dr. Charles Houston are two of the best.
The best advice is to learn to listen to your body, pace yourself, and remember, the more you get out there, the easier it gets.