go through, and then phone call to my wife. reporter: a christmas service where soldiers take time to reflect. their thoughts and prayers are with families, front line troops and fallen comrades. peace on earth reporter: the words of this carol have a special meaning here, as they ask for peace on earth and mercy mild. kiko itasaka, nbc news, camp eggers, kabul. in health news this morning, this is the time of year when many of us are resolving to exercise more, yet studies show january is usually when people work out the least. experts say this is largely because of the weather. nbc s erica edwards takes a look at ways you can get your body moving when everything around you is freezing. reporter: drudging through the snow on a subzero, arctic day, is not how most people want to burn their holiday calories away. the good news is there are a lot of exercises you can do without leaving your heated home. an empty bleach bottle or something, put water in it or