Thermogenesis is the process of heat production. Non-shivering thermogenesis usually occurs in brown adipose tissue (brown fat) that is present in newborn and hibernating mammals and in human infants. It is a process where substances such as free fatty acids (derived from triacylglycerols) remove purine (ADP,GDP...) inhibition of thermogenin (uncoupling protein-1) which causes an influx of H+ into the matrix of the mitochondria and bypasses the ATP synthase channel. This uncouples oxidative phosphorylation and the energy from the proton motive force is dissipated as heat rather than producing ATP from ADP.

One way Thermogenic methods can be classified are:

1. Exercise associated thermogenesis (EAT)
2. Non-exercise associated thermogenesis (NEAT)

Based upon whether they are or are not initiated through locomotion and intentional movement of the muscles.

Physiology