Contact sports and microbiota

Someone did a study on microbiota exchange between athletes during competition. Interestingly enough they chose roller derby as the sport...

Bottom line - by the end of the match where everyone is in contact with each other the individual's microbiota are much more similar to each other. See the figure below - this is an ordination that clusters individuals together based on their microbial composition

http://bodyodd.nbcnews.com/_news/2013/03/12/17270650-roller-derby-skaters-trade-bumps-bruises-and-bacteria?lite

https://peerj.com/articles/53/  for the original journal article. Here's one of the key figures:

I can only imagine what this would look like for something like wrestling