Are you huffing and puffing more as you walk down the streets of Breckenridge? Don't worry; it's normal. So is the fact that you're peeing more (and if you're not, you may not be drinking enough water) and having strange dreams. About 20 percent to 30 percent of people suffer from altitude sickness, according to a 1980s study at Keystone Resort in conjunction with formal local doctor James Bachman.

At elevations above 6,000-8,000 feet, the body needs to adjust to the decrease availability of oxygen. Every breath contains fewer molecules of oxygen, resulting in less oxygenated blood. The lack of oxygen in the blood causes extra blood to rush to the head, often causing headaches, nausea and shortness of breath.

Symptoms of altitude sickness include a headache with one or more of the following:

loss of appetite and nausea or vomiting

fatigue or weakness

dizziness or light-headedness

difficulty sleeping

confusion

staggering gait

Flue-like symptoms usually start within the first three days at high elevation and end by the fourth. It can happen to anyone, though genetics, rate of ascent, alcohol and other depressants as well as overdoing physical activity can contribute to a person's predisposition. Most symptoms diminish with rest and acclimatization, but if you have trouble breathing or thinking or have a sever headache or nausea and vomiting, go to a clinic.

HOW CAN I PREVENT A HEADACHE?

Stay in Denver for a night or two if you're coming up from sea level. Avoid alcohol — it has a stronger effect in high elevations — and avoid sleeping pills and narcotics. Take it easy the first couple of days; physical conditioning at sea level does not help.

TO TREAT IT

Once again, avoid alcohol and other depressants. They decrease respiration and make symptoms worse. Drink plenty of fluids. Avoid intense exercise; mild exercise

is OK. If nothing works, return to a lower elevation, such as Denver.