When it comes to outdoor exercise, dressing right is as important as warming up to contend with current fluctuations in the weather.

People who exercise in this weather must take special care to dress correctly, said John Lucas, a professor of exercise and sport science. People should always check the weather reports before exercising and try to approximate what the weather will be like by the end of the workout, he said.

"Especially if the workout is lengthy, the weather could change," Lucas said.

Other important factors to consider are the wind chill factor and the direction of the wind, he said, adding that the temperature outside might be 40 degrees, but a 15 mph wind can drop the temperature below freezing.

The best clothing strategy for outdoor exercise during the winter is layers, said Bob Ricketts, an instructor in the department of exercise and sports science.

The layers must perform three basic functions - absorption, insulation and weather protection, he said.

The absorption layer should "whisk moisture away from the skin," he said, adding that wet skin loses body heat 25 times faster than dry skin.

The insulation layer should be heavy enough to keep people warm even in the early morning, when the temperature is usually colder than later in the day, Ricketts said. Wearing layers, such as a flannel shirt and a sweater, provides warmth while allowing people to adjust to possible increases in temperature.

The outer layer should allow moisture to escape and also function as a windbreaker, Ricketts said.

"Ideally the outer garment will allow you to cool and protect you from the wind," said James Hodgson, associate professor of applied physiology at the Lab for Human Performance Research, 199 Noll Lab.

Ricketts said down-filled jackets are not what they are cracked up to be.

"There is a misconception about the down-filled jacket," he said. "Once it gets wet, it loses a lot of insulation (capability)."

A reliable choice for outer wear is a double-faced pile coat, Ricketts said. A garment made from this material does not have the weight or bulkiness of wool and insulates even when wet, he said.

A person dressed in too many layers runs the risk of heat exhaustion because the layers prevent the body from having a way to cool down, Lucas said.

Joggers should wear two to four layers of thin cotton clothes beneath a protective sweatsuit, Lucas said, adding that fingers, ears, and other extremities should be protected from frostbite.

Joggers could also wear poly-propylene runnings suits that are designed to keep the skin dry, with a T-shirt and shorts and a windbreaker, Ricketts said.

Ricketts recommended getting inside a warm place as soon as possible after exercising to avoid the body temperature from dropping too quickly and risking hypothermia.

Cross-country and downhill skiers alike should wear something that is waterproof, said Steve Romano, a salesman at Appalachian Outdoors, 324 W. College Avenue.

"Probably the best bet would be gortex, because it's light weight and breathable," he said, adding that gortex is a synthetic fabric used by several different companies that make exercise apparel.

Brian Fike, an instructor at Tussey Mountain Ski Area, said although it is unnecessary for skiers to wear hats when the temperature warms up, he recommends that they wear gloves to prevent frostbite.

But appropriate dress alone does not ensure a healthy workout, Lucas said, stressing to would-be exercisers: "Always remember that you must be aware of your own limitations and fitness. Don't overtax yourself in the beginning of any workout program."