Shivering is an energetically expensive form of exercise that burns carbohydrate, not fat.

“Shivering is exercise. So, here's where we are now, we talk about this little bit, the metabolic winter. Our body, which is... You know, I believe exercise is mimicking cold stress. I believe most of the benefits that we're seeing because here's what happens. If I have people exercising and they start to shiver, I'm sorry, sort of exercising, not shivering, they start to exercise, they produce irisin. Irisin is known to up regulate and create more brown adipose tissue. We've seen these studies and it's come out in the last three years or four years. With shivering, shivering is the original exercise.”