Q. What are good tips for exercising outside during cold weather?

A. Bravo! For most of us, keeping moving throughout winter—and getting fresh air and sunlight in the process—is good for the body and soul.

First, though, the caveats. Because cold winter air—especially when it's dry—can trigger breathing problems, consider moving your workout indoors if you have asthma or other conditions that compromise the upper respiratory system. At the very least, wear a scarf over your mouth and nose so the air is warmed before inhalation.

Next, dress smart. Most important: an innermost layer that wicks away moisture (such as Dri-Fit, or another polyester-based fabric) and an outermost layer with a bit of reflective material, to increase your visibility on gloomy winter days. You'll peel off layers as you warm up, but remember to add them back during your post-workout cool-down, so you don't become chilled.

Before you really get started, walk for 10 or 15 minutes to raise your body temperature. Then stretch. Cold muscles are more susceptible to injury.

Finally, remember to hydrate—before, during, and after exercise! This is just as important as it was in summer, and much easier to forget when you don't feel as thirsty.

This Q&A was written by Victoria Dolby Toews, MPH, a health journalist based in the Pacific Northwest, where she and her family enjoy hiking and cycling.