Buh-bye, frigid air; hello, sunshine! With warmer weather blowing through your neighborhood, now's the time to hop off the treadmill and hit the open road. Exercising in fresh air is bound to make you happier and will help you get your daily dose of vitamin D, but it might be a little rougher on your joints since treadmills are more forgiving than concrete and asphalt. Plus, moving your run outdoors means you lose the assistance of the treadmill pulling your legs backward , so your body works harder striking the ground with a bit more zeal. Use these tips to make the transition as smooth as possible.
Ease Into It
Move your runs outside gradually to allow your joints time to acclimate to the new running surface. Add one or two new outdoor runs to your regimen each week, decreasing the number of treadmill runs you do until all your runs are outside. Run shorter distances at first, gradually increasing mileage as your body is ready. Running too much too soon can cause shin splints, but so can weak shins. Try this shin-strengthening exercise  and these calf stretches  to prevent this common running issue.
Be a Tortoise
You might feel slower running outside with wind resistance, unpredictable road surfaces, and the challenge of propelling yourself forward off of solid ground. Be OK with your slower speed — you might feel so inspired by the beauty of nature that you won't even notice your pace. As your body becomes stronger, your pace will naturally increase. You might want to hold off on running with someone else since their speed may push you too hard, unless you can find someone who runs at the same pace as you.
Go For a Soft Landing
Start off on a dirt trail or a spongy outdoor track; these surfaces are more joint-friendly than pavement. If a trail or track is hard to come by, try to avoid concrete sidewalks and run on asphalt instead, which has more give. If you're on a busy road, remember to run against the flow of traffic so you can see oncoming cars.
Take It Easy on the Hills
Even if you're used to pumping up the incline on the treadmill, hills outside can be much steeper, and that coupled with wind and blaring sunshine can make hills feel even more challenging. Look for shorter, less steep hills, and don't be afraid to stop midway and walk if you need to (you're still working your thighs and booty). Running uphill can make you feel like a superhero when you crest over the top, but running downhill is surprisingly rough on the quads and knees. Here are some tips for running downhill  — you can learn to love the descent.
Use Map My Run  to find new running routes in your zip code. You can also map out your route ahead of time to check your mileage and elevations to ensure there are no hilly surprises midrun.
Before heading out, let someone know where you're going and the time you're expected to return, so in case something happens (you fall and twist an ankle or get lost in the woods), someone will know to look for you. Running with an ID or Road ID bracelet is also a smart idea. Running outside means you'll encounter other people, cars, and dogs, so keep the volume of your iPod down so you can hear what's going on around you. Don't forget the sunscreen and any other protective gear like sunglasses or a hat that you'll need in the elements. If running at night is unavoidable, be sure to follow these night running tips .