Crochet Muscle Strain Remedies, Anyone?

Since February, I've been beginning to work with worsted weight cotton again in earnest.  I have to get my inventory up for the summer market and events!  And boy, do my fingers hurt.  It's not only my digits - I'm finding that my elbows and shoulders are taking a beating, too.

What to do?  I am alternating the heavier items with lace scarves and berets in lighter weight organic cotton, bamboo and acrylic blends to relieve some of the strain.  My boys give really good neck and shoulder massages, for which I am immensely grateful.  A parafin dip machine may be in my near future.  Yoga stretches help, too.

What do you do to maintain your crochet muscles and relieve overwork?  Suggestions welcome!