Originally Posted by terrymorse

So it's cold out, do you take an outdoor ride or stay indoors?

Well, if you're looking for excuses to stay cozy and warm indoors, cold weather reportedly can:

• cause heart attacks
• damage your lungs

This is from an article by Dr. Mirkin, Exercising in Cold Weather:

• causes your body to produce adrenalin which constricts your arteries and raises your blood pressure
• thickens your blood and makes it more likely to clot
• causes the liver to make more fibrinogen that increases clotting
• raises cholesterol levels
• may reduce your body temperature, which weakens your heart muscle
• may induce exercise-induced asthma