Icy Hot, hmmmm, interesting, hadn’t thought of that. Thanks.
Another trick to use is to bake several large rocks or bricks in the oven to heat them through. Then wrap them individually in a towel/blanket and put your feet on them while you’re sitting. (Put one at the foot of your bed under the covers and you’ll stay warm and cozy all night. They do that in Africa on safari trips.) Hot water bags work too but they don’t last as long.