Methods and systems for determining freezing of skin during cooling

A cooling system for reducing adipose tissue in a subject by cooling a skin portion of the subject, the cooling system comprising;

• a base station;
• an applicator that includes an electrically conductive cooling element having a cooling surface that is configured to contact the skin portion of the subject for the purpose of cooling the skin portion of the subject, the cooling surface of the cooling element being substantially electrically non-conductive having an electrical resistivity of 1,000 Ω·cm or more;
• and
• a controller that is configured to determine a freezing of the skin portion of the subject based on a time derivative of a first electrical impedance between the cooling element and a first return electrode configured to be placed on a body of the subject, the controller also being configured to determine a movement of the subject or a movement of the skin portion with respect to the cooling element by determining an electrical impedance between a movement sensor electrode and a movement sensor return electrode.