An article out by Yoga Journal (http://www.yogajournal.com/lifestyle/2808) encourages heart opening poses for an immune system boost. My winter heart opener of choice…Camel and Half Camel.
Camel and Half Camel are supported enough for my at times tight winter muscles, but will encourage me to really build enough heat in my core before trying them. They are just hard/easy enough!
Go ahead and add these into your practice and let me know how it goes! Have a favorite winter pose? Post in the comments below!