The thermometer has dipped below freezing and the shorter days are gray and cloudy. If you’re a diehard runner tired of cranking out miles on the treadmill, these obstacles probably aren’t stopping you from heading outside. But before you lace up your shoes, you’ll want to keep safety in mind.

“Running in the winter is a great way to maintain physical fitness,” says Geisinger sports medicine specialist Justin G. Tunis, MD. “However, unlike summertime where you can just throw on a pair of shorts and go, you’ll need to prepare a little more in order to stay safe.”

Five ways to prepare for your run

Keep these tips in mind before you head out for a winter run:

1. Stay visible

The fewer daylight hours during the winter months mean that you’ll likely be running in the dark at some point. Wear bright, reflective clothing and carry a small light — one that will clip to your clothing or sneakers — so that motorists can see you. Also, never trust that a car will be able to stop in time to avoid you in the road.

2. Keep dry

Even though you’re running in cold weather, you will still sweat. The layer of clothing closest to your skin should be a wicking technical fabric, the kind that moves perspiration away from your skin. If you’re wet, you’ll put yourself at greater risk for hypothermia and frostbite when the temperature drops below freezing.

“Many runners forget that they’re still perspiring when they run in the winter since they don’t feel hot,” says Dr. Tunis. “This can lead to dehydration, so make sure that you drink enough water to stay hydrated.”

3. Wear appropriate footwear

The running shoes you use during the summer may not work well for winter runs. If there is snow or ice on the ground, you’ll need waterproof shoes with extra grip to keep you stable. Look for removable spikes that slip over your regular running shoes for added traction.

4. Cut back on the mileage

Slow your pace and reduce your mileage on brutal winter days, just like you would at the height of summer. The cold increases your lactic acid production at a given pace, indicating that your body is working harder to produce enough energy to keep you going. You’ll still get a great workout even if you slow down.

5. Know when it’s better to cross train

Sometimes the risks of running outdoors in winter outweigh the potential benefits. Recognizing when it’s better to workout inside on a treadmill, on exercise bike or in the pool can save you from injury. It will also make you a more well-rounded athlete.

“Running in the winter puts you at greater risk for injuries, such as sprained ankles from slipping and falling on the ice,” says Dr. Tunis. “Runners should recognize that healthy wintertime running is a balancing act between maintaining fitness while remaining safe.”

If you decide to run outside this winter, follow these tips — and always use your best judgment before heading out into the ice and snow.