Q: Why do NFL players who expose their arms in subfreezing temperatures not get frostbite?

— Anne Lummus, Marietta

A: There is a risk of frostbite in games played in subfreezing temperatures, but all NFL teams have medical personnel on the sidelines whose duties include monitoring the players for all weather-related symptoms, including frostbite, heatstroke and dehydration. Ears, noses and fingers are the biggest concern in cold weather, Dr. Matt Matava, head team physician for the St. Louis Rams and president of the NFL Physicians Society, told ESPN.com. Players who choose to go sleeveless during games often protect their exposed arms with Vaseline or other petroleum jelly products, the article stated. Teams provide their players with parkas with hoods, heated benches, helmet warmers, heaters and warm packs for their hands and feet.

Q: Regarding the Bush twins, I know Jenna is on “Today.” What happened to Barbara, Jenna’s twin sister?

— Doris Keith, Acworth

A: Barbara Pierce Bush, 32, is the co-founder and CEO of Global Health Corps, which connects young professionals with organizations working to provide and improve health services in African countries and the U.S. Barbara graduated from Yale in 2004 with a degree in humanities. She interned for UNICEF in Botswana and previously worked at Red Cross War Memorial Children's Hospital in South Africa and the Smithsonian's Cooper-Hewitt, National Design Museum. She is on the board of several organizations, has worked with the United Nations' World Food Programme and is on the U.N. Foundation's Global Entrepreneurs Council.

Andy Johnston wrote this column. Do you have a question about the news? We’ll try to get the answer. Call 404-222-2002 or email q&a@ajc.com (include name, phone and city).