Microwave-heatable exercise putty in a container with temperature indicator

A method for microwave-heating a therapeutic exercise putty to an acceptable therapeutic temperature in the range of about 40 degrees C. to about 60 degrees C. comprising:

• a) packaging a mass of therapeutic exercise putty in a microwaveable container having at least one transparent wall, said putty mass being in heat transfer proximity with said transparent wall;
• b) affixing thermochromic heat sensitive semiconductor material to said transparent wall within said container and in intimate heat transfer contact with said putty mass, said thermochromic material yielding a visual first indication when the temperature of said material reaches about 40 to about 47 degrees C. and yielding a visual second indication when the temperature of said material reaches about 54 to about 60 degrees C.;
• c) heating said container and said contained putty mass in a microwave oven for a period of time and under microwave power conditions estimated to heat said container and putty mass to a temperature of at least about 40 to about 47 degrees C.;
• and
• d) inspecting the transparent wall of said container to determine whether said contained putty mass has been heated to a therapy acceptable temperature of at least about 40 to about 47 degrees C. as established by said visual first indication of said thermochromic material and not more than a non-acceptable therapy temperature of over about 54 to about 60 degrees C. as established by said visual second indication of said thermochromic material.