8/11/14 - The next time your gym partner says "That's a crappy hold!" she may mean more than size or texture. In a study published this summer in Current Microbiology, researchers found that every gym hold they tested had traces of microorganisms associated with fecal matter. The analyses "suggest the presence of a fecal veneer on indoor climbing wall holds," the report said.
Researchers swabbed the surface of three holds each from four unnamed gyms in New England and North Carolina in 2011. The 12 holds tested were all at the start of the routes, and each had not been washed in at least a month. DNA extracted from the swabs was analyzed for the presence of microorganisms of various types.
The study's lead author, Dr. Suzanna Bräuer, associate professor of biology at Appalachian State University in Boone, North Carolina, explained that the microbes present on the holds are associated with the general environment (especially soil), human sources (skin and mouth), and feces (either human or animal).
The study found that the proportion of microbes from environmental sources was higher than that found in similar studies of microorganisms in other indoor environments, compared with human sources. "Because human-associated microbial communities typically contain a higher abundance of human pathogens and/or opportunistic pathogens, one might infer that climbing holds potentially pose less of a health risk compared to other indoor environments," the study concluded.
But what about that fecal veneer? Dr. Bräuer, a climber who frequents a gym with her husband, said in an email that, "Although it's impossible to say from our study, I would think that the most likely source of the fecal bacteria would be dog or animal feces. If the hold did contain human fecal material, and IF the E. coli were pathogenic, it would pose a major threat. I think that's very unlikely, but again it's impossible to tell from the type of data that we collected. All we know is that E. coli were strongly present. I would guess this would be from outdoor sources."
In other words, the most likely source of the fecal material on gym holds is whatever climbers stepped in at the crag—which they then tracked into the climbing gym and onto its routes.
What can climbers do about it? The study noted, "While this does not necessarily represent a significant risk, climbers should take precautions, for example, by washing their hands both before and after climbing." Washing the soles of shoes also may help—with the practical benefit of increasing the rubber's stickiness. And, as Dr. Bräuer noted, "My colleague and coauthor Dr. Erik Rabinowitz believes strongly that climbing gyms should wash holds more frequently."
Date of report: June 2014
Sources: Current Microbiology (June 28, 2014), Dr. Suzanna L. Bräuer