What causes ringworm in grapplers?

Why are grapplers so prone to getting ringworm? I've heard a lot of grapplers talk about having it.

It's called "sharing".... MMA is such a sharing sport! :-)

Is ringworm actually a worm? Or is it just a skin irritation?

Haven't really had much knowledge of ringworm.

What is ring worm?

There are several different types of ring worm! Learn what they are and how it is treated!

http://az.essortment.com/whatisringw_rvvv.htm

http://www.skinsite.com/info_tinea_corporis.htm

http://www.amateurwrestler.com/health/ring_worm.html

dirty mats and people who play with their dogs and then go grapple.