As a general rule, it is safe to exercise outdoors in freezing temps as long as you pay attention to the signs and symptoms of specific cold-weather dangers. The three primary concerns are frostbite, hypothermia, and heart attack. Wind chill and time exposure are critical factors to consider when you are attempting to exercise outdoors. Learn the symptoms of impending trouble to avoid danger. Numbness or tingling of the hands, feet, ears, or nose signal early frostbite. Shivering, slurred speech, loss of coordination, and unusual fatigue signal hypothermia. Breathing cold air can trigger lung bronchospasm and coronary vasospasm in addition to placing an additional load on the heart. If you experience any chest pain, stop immediately and seek medical attention.