To increase metabolism via deliberate cold exposure, it is advisable to reach a shivering state.

“And there are several ways that you can use shivering, you can leverage shivering and you can leverage cold to accelerate fat loss. But you have to do it correctly.”

“I described a protocol involving getting into cold of some sort, whether or not it's ice bath, cold shower, some form of cold could even be a river or an ocean if you have access to that and inducing shiver and then getting out, not crossing your arms or huddling but allowing that cold to evaporate off you and continuing to shiver and then getting back into the colder environment of water or stream or shower, et cetera.”

“Sure, so deliberate shivering without cold is essentially what happens when you get a fever. Your set point goes up in your hypothalamus and you actually, even though you're a normal body temperature, your thermostat is telling you you're too cold, increase your metabolism.”

“So if your primary goal is to induce increases in metabolism, both in the short term and in the long term, following the cold exposure, well then you'll want to end on cold and you'll want to find a way to shiver provided that the level of cold that you're exposing yourself to is still safe for you overall.”

“if you want to use deliberate cold exposure to increase metabolism, that you should make sure that you get to the point where you shiver.”

“Now, it should make sense why shivering is one of the strongest stimuli that one can incorporate to stimulate fat loss. Now, shivering is almost always associated with cold. We think shivering, we think cold because when we get cold, we shiver. There are two ways that shivering can increase fat loss. There are several ways that you can use shivering, you can leverage shivering, and you can leverage cold to accelerate fat loss, but you have to do it correctly.”