It's none of your business to know about my health. Period sis
This is likely due to peripheral vasoconstriction. This happens in order for the body to retain heat longer in order to protect the body from hypothermia. The skin would act as an insulator of the organs and water. Also, when this happens, it would allow more of the oxygen to be transported to the oxygen sensitive organs like the brain and the heart.
With good body posture you would be able to ski much more better than having bad body posture