Among novel ideas I heard between rich meals this past week was to breathe cool air, walk outdoors in the cold, and take (get ready for this one mentally) cold showers to boost one's immune system and acclimate better to the cold. I heard of other versions of using cold from a few schools of thought in the past few years including taking 'hot and cold intervals of a couple of minutes in a shower' (ending with a cold rinse) which was a way to get ready for spring I think in the 5 element Chinese medicine protocol.
Mostly the idea was to scrub with a cloth the lymph glands under arms and