Thought I would share this.

I have a semi-mild case of Tennis Elbow (or the much scarier sounding 'lateral epicondylitis').  It was cause by non-violin related sports injuries from years past, but now will sometimes manifest itself while I play.  It is in my right arm (bow arm), and after practicing for a good spell, the repeated motion of bending and then unbending my elbow will cause soreness that leads to dull pain.  Sometimes it starts while playing but more often it kicks in after I set my instrument down.

There is a nice piece of equipment used in weight lifting and powerlifting that works wonders for me.  It's called an elbow support or elbow sleeve.  It's a compression sleeve that you can slide on and off your arm with ease that puts a gentle but firm amount of pressure on your elbow joint.  This helps to hold everything in place, keep the joint warm, and improve circulation.  I still have full range of motion when I use it, and I can't discern an effect on my playing.  However, it does a good job at preventing soreness and any pain that might crop up, and I highly recommend one if anyone has this same issue as myself.

There are about a million different brands and construction materials, but the one I use is linked below.  Cheaper to order online, but they can be found in most sporting good stores.

qid=1425319520&sr=8-1&keywords=mcdavid+elbow+sleeve