Your deck isn’t just for barbecuing. Place a yoga mat on those planks and you have a picturesque, open-air yoga venue. But don’t lose the local studio schedule. Depending on the time of day you practice the air quality could be so poor that you are better off om-ing indoors.  According to a 2006 study by Toronto Public Health, high levels of pollution, pollen, and ozone make the hours between sunrise and sunset unfit for vigorous exercise in urban areas or near congested highways. Kim Manfredi, owner of Charm City Yoga in Baltimore, has decks at both of her studios for outdoor yoga classes. But she says, once the air quality flag gets waved on the news, the classes come inside. 

If you have the right setting like a National Park, om on. The beauty of an outdoor practice is you get the chance to be close to and be inspired by nature. Don’t forget yoga poses are all named for items in nature (dolphin, tree, mountain, etc). Jennifer Schelter, owner of Yoga Schelter studio in Philadelphia holds one of her classes in the Morris Arboretum. “The outdoors are beautiful and itchy and scratchy and the ground is sort of dirty and I love the mess,” she says.

Instead of missing out on posing in a park or making yoga part of your post-run routine, here is a list of ways to avoid the pitfalls of an outdoor practice.

Allergy Alert
In the spring, pollen and mold counts are highest in the morning, says Mari Jones, a respiratory therapist in Wichita, Kansas.  Your best bet: an afternoon or evening class will have cleaner air.

Sunburn
Location and gear are essential components of a healthy practice. Posing in direct sunlight is not recommended. Most likely, slathering on the SPF will make your mat greasy and slippery so invest in a shirt treated with SPF protection and aim for classes when the sun isn’t so strong.   “We have classes outside at the transition times of day,” Manfredi says.

Pollution
The Toronto study found that carbon monoxide and nitrogen dioxide were at their highest levels during rush hour. If you are in a place with proximity to the highway, practicing before 7 a.m. and after 8 p.m. will keep your lungs toxin-free.