People who are in pain often wonder, "should I use heat or ice?" Heat is the answer almost every time. From an acupuncture perspective, many pain conditions are caused by stagnation. Things are not moving smoothly through the channels, causing blockages that lead to pain. Acupuncture restores flow, helping to eliminate these blockages. Looking at pain in this way, ice is counterproductive--it causes things to remain stagnant and slows down the healing process.
You do not have to be injured or in pain to benefit from this warming principle. When we are cold, we get tight--we tense our shoulders and hold ourselves in rigid postures. This can be an issue even in summer, when offices, resaurants, and other places hike up the air conditioning to the point of discomfort.
So, choose heat over ice. Bring along an extra layer. Wear a scarf. Drink warming teas (ginger or cinnamon are good). Keep your self warm inside and out to maintain a healthy flow.