INTRODUCTION:
Recreational opportunities such as skiing, backpacking, hunting and fishing require physical demands from your body. These demands can be increased dramatically by the unique environment of high altitude. This information is being presented to help you have a healthy and enjoyable trip to high altitude areas.

WHAT IS HIGH ALTITUDE?
Broadly interpreted, high altitude could be anything about 5,280 feet (1,609 kilometers) in elevation. Approximately three-quarters of the nations' land above 10,000 feet lies in Colorado. Colorado's average elevation is 6,800 feet. Estimates are that more than one-half of Colorado is over 5,280 feet in elevation. It seems reasonable to say much of the time you spend in Colorado will be in high altitude areas.

WHAT ARE THE EFFECTS OF HIGH ALTITUDE?
At high altitudes, everyone is affected somewhat. The effects vary among individuals and cover a variety of symptoms. The two main differences between the high altitude environment and sea level areas are decreased oxygen density and decreased humidity, or moisture content, in surrounding air. At an elevation of 8,000 - 10,000 feet, the oxygen is approximately 40-45 percent lower than at sea level. A sudden change in environment from sea level to high altitude can produce symptoms of nausea, insomnia, diarrhea, restlessness, shortness of breath and air hunger. Palpitations or fast heartbeat, headache, nasal congestion, coughing, increased flatulence of "gas", fatigue and intolerance to exertion may be experienced. If the high altitude experience progresses, more shortness of breath and increased coughing and edema (fluid accumulation in the lungs) may occur, requiring medical attention and possible hospitalization.

WHAT CAN BE DONE TO ADAPT TO HIGH ALTITUDE?
The initial complaints should disappear as your body adjusts to the lowered oxygen content and dryness. This may take anywhere from a few days to a few weeks. Upon arrival to high altitude, do not overdo. Eat lightly. For the first 48-72 hours, avoid alcohol. Alcohol aggravates the high altitude syndrome. Most of all, keep physical exertion to a minimum for the first day. Over-exertion before your body can adapt to the lower oxygen and dryness can result in more severe and persistent symptoms. If you are over 35 and plan strenuous activity while in high altitude, it would be best to check with your doctor first. If you have a history of heart, circulatory or lung disease, it is mandatory to check with your doctor before coming to high altitude. Respiratory infections such as pneumonia should be completely resolved before coming to altitude, since they can be dramatically worsened by the extra strain placed on your body. Pregnant women should seek the advice of their physician before exerting themselves at high altitude.

SOME FINAL SUGGESTIONS:
Rest appropriately and do not overdo the first two days. Taken a nap when sleepy and get a good night's sleep after an exertive day of skiing or backpacking. Eat lightly and drink plenty of liquid, but avoid alcohol for the first 48 hours. If you experience any symptoms that were mentioned, you may be suffering from oxygen deficit. The symptoms can be used as a caution light to decrease your activity and protect yourself. A day of rest at this time is strongly suggested. If your symptoms are not improved or symptoms develop that worry you, do not hesitate to contact a local physician in the area. It is very easy to call a doctor's'office or the Emergency Room at the local hospital to talk to the nurse or doctor on duty if you have any questions about your arrival to a higher altitude. You are in a high altitude area to enjoy your vacation. It is tempting to do as much as possible. But vigorous skiing the first day followed by a big meal with alcohol and more skiing early the following day can lead to high altitude symptoms and spoil a vacation which was looked forward to and possibly expensive.

Written by: Barry D. Mink, M.D.
For the American Heart Association of Colorado, Inc.