Multi-day hikes, ultra-marathons and other outdoor activities in the mountains are a part of many athletes' travel plans. While you may have invested in top of the line hiking gear, apparel and camping supplies, one factor you may not have planned for is the effects of altitude on your body. Planning ahead for altitude changes is key in making sure you have a positive experience on your mountain adventure.
The Facts
Breathing becomes more difficult at higher altitudes, especially if you are used to living at or near sea level. Altitude is defined by high --- 8,000 to 12,000 feet --- very high --- 12,000 to 18,000 feet --- and extremely high --- over 18,000 feet --- but even going only as high as 5,000 feet to a city such as Denver will change your breathing ability if you are coming from sea level. At 12,000 feet, your body is only getting 60 percent of its normal level of oxygen molecule per breath, meaning even in a resting state you are working harder to get oxygen into your lungs.
Acclimation
A study in the International Journal of Sports Medicine suggests that acclimation, or staying an extended period of time at high altitude, is the best way to improve performance in high-altitude activities. Hypnosis may also be helpful. If you do not have the opportunity to live in a high altitude area or access to an experienced hypnosis specialist, plan to spend at least one to three days at your initial high altitude destination to allow your body to adjust. Hydration is very important, as is a diet consisting of 70 percent carbohydrates. Your body will need the extra water and energy from carbohydrates as breathing requires more energy at high altitude.
Endurance athletes have often sought the benefits of training in altitude. However, even with acclimation, VO2 levels are decreased, which makes slower speeds require the effort level of higher speeds at sea level. The benefit of training at high altitude is that racing at sea level feels significantly easier (See Reference 2).
Illness
As the air pressure lowers at higher altitudes, fluid begins to leak from your capillaries and builds up in your brain and lungs. You will start to feel symptoms of what is commonly referred to as altitude sickness, which includes severe headaches, weakness in joints and nausea. To avoid these issues, be cautious in your activity level in the first 24 hours of experiencing high altitude. If you start to feel ill, stay at the same altitude until you feel better. If you feel worse, start to descend.
Considerations
Avoid alcohol and drugs, including sleeping pills, while adjusting to altitude as they can contribute to the negative effects on your body. If you know you have adverse reactions to high altitude and plan to take many trips to the mountains, you may want to invest in a Gamow Bag. Igor Gamow developed this portable hyperbaric sleeping bag-like chamber to mimic conditions at sea level, which may help alleviate your symptoms. If you have a heart condition, it is advisable to stay out of high-altitude situations as blood flow to cardiac muscles will become reduced.
References
- Princeton: Outdoor Action Guide to High Altitude: Acclimatization and Illnesses; Rick Curtis; 1999
- International Journal of Sports Medicine; A practical approach to altitude training: where to live and train for optimal performance enhancement; B.D. Levine and J. Stray-Gunderson; 1992
- Lemelson-MIT Program: The Gamow Bag
- MGIO: Elevation & Altitude
