Winter Training

Winter is for Storing Qi.  Winter is the time to just maintain your practice.  At this time we try not to lose anything we’ve developed or gained, and of course we try not to get injured.  It is the time to practice lots of stillness.  This kind of practice is called returning to the root, stillness "tonifies" the Kidneys.  In contrast it is also the time to perfect circulation.  Lots of Winter practices have to do with testing or improving circulation, they include, various types of bathing, scrubbing, pounding, slapping, scraping, shaking, etc...
When Winter comes I will share some techniques for improving circulation and developing vigorous weiqi (the qi on the surface of the body.)

Why do we practice differently in different seasons?  Does it have a benefit?  Is there some fruition?