Low level laser light
Low level laser light reduces the stability of adipocyte cell membranes, allowing cells to release their stores of fat without damaging the cell. Because the fat is released into the extracellular space, cardio based exercise is usually promoted after the procedure. Exercise increases lymph flow and is thought to also promote the use of the lipids as an energy source. This is also why adequate hydration is encouraged. The laser technologies are differentiated mainly by the wavelength of light used.
Focused thermal ultrasound techniques work by raising the tissue temperature above 56 °C, resulting in coagulative necrosis of adipocytes, with sparing of vessels and nerves. Passive heating of the skin may also induce collagen remodeling.
Radiofrequency devices work by producing an alternating flow, which creates an electric field over the skin. The electric field shifts polarity millions of times per second, that causes a change in orientation of charged particles.
Cryolipolysis is the term for using cryogenics to induce lipolysis. Adipose tissue is cooled above freezing causing localized cell death and inflammation.