Warmer

I have disability and one of my many medicines has a side effect of always making me cold. Luckily living South Florida I can cope well, but inside public places I have issues handling the air conditioning. I am looking to make a wearable that can keep me warm. Possibly a something like a wristband. I found the electric heater found at https://www.sparkfun.com/products/11288 or https://www.sparkfun.com/products/11289. How can I power this with a battery and regulate the temperature? I was thinking of using Knit Conductive Fabric found at https://www.sparkfun.com/products/10056, but not sure how to use it. Looking for ideas and help. Thank you!