ST. LOUIS – Planet Fitness will offer free access to its St. Louis-area gyms through the weekend in response to air quality concerns around the region.

Dense smoke from Canadian wildfires has led to unhealthy air quality indexes around Missouri and Illinois in recent days. St. Louis is under an “orange” air quality ranking Thursday from the National Weather Service. Health experts say, based on that ranking, sensitive groups should limit time outdoors, including exercise.

In response, Planet Fitness has opened 17 gyms in the St. Louis-area to anyone wanting to exercise, including non-members.

“With seventeen Planet Fitness clubs in and around the St. Louis area, we want to make sure those who normally exercise outdoors have a safe option to avoid unhealthy air quality levels,” said Midwest Brands CEO Mike Hamilton who runs the Planet Fitness franchisee group. “As the leading fitness provider in the St. Louis area, we want to make sure we are responding appropriately to this situation. We hope this free access gives everyone the opportunity to exercise safely and continue their healthy habits.”

The limited-time offer is good for St. Louis-area locations in Overland, Shrewsbury, Crestwood, South County, Ballwin, Alton, Edwardsville, Mid Rivers, Wentzville, Washington, Festus, Central West End, Fairview Heights, Mt. Vernon, Chippewa, Florissant and Ferguson

Planet Fitness locations offer more than 100 cardio and strength equipment pieces, 30-minute circuit training areas, functional training and various amenities.