Today we are going to tackle a question we get regularly: does showering before swimming really make that big of a difference? Does it help that much? Some of the leading voices in the aquatics associations seem to think so, but this wouldn't be the first time we have a contrarian opinion...
What does a shower before swimming actually accomplish?
Let's start with the science behind this practice. There are two main reasons to shower, and the credible health organizations care far more about one than the other. The two reasons are to 1) remove fecal matter to reduce risk of water illnesses, and 2) remove non-living organics and oils from the body to reduce the oxidant demand. According to the Water Quality and Health Council:
A thorough shower with soap helps remove perspiration, body oils, cosmetics and traces of urine and fecal matter on the body. Sending those substances down the shower drain goes a long way toward reducing the “yuck factor” for everyone who shares the pool, but there is much more to consider.
Sure, the "yuck factor" is not exactly a scientific term, but it gets the point across. From a scientific perspective, getting traces of fecal matter off the body is an obvious benefit for public health and safety, and getting sweat and traces of urine off the body helps reduce combined chlorine before it can form. No disagreement there. And from an oxidant demand perspective, showering off non-living organics like body oils and cosmetics is also a benefit to reduce chlorine demand. So far so good, at least in theory.
A shower prior to swimming should remove most cosmetics, body oils, sweat and other nasties on our bodies. But mind you that most swimmers–if they shower at all–will shower in their swimsuit. This makes the removal of "traces of fecal matter" difficult. Gross...we know. And to be honest, the removal of fecal matter is the primary purpose of the shower for health reasons, because according to the CDC, most Recreational Water Illnesses (RWI) are passed through feces that slough off into the water. Even more disgusting...we know.
Even BuzzFeed parroted this information from the CDC, saying that diarrhea is the primary reason for showering. It appears the health and safety experts care most about RWI, and those are certainly important to avoid. Pools need to be safe and healthy to swim in. To be clear, we do not disagree with the CDC and other health organizations on this topic. We absolutely want to prevent RWIs like crypto.
Related: Pool Water Chemistry Resources
The question gets back to theory vs. reality. How do showers occur in the real world? As mentioned earlier, swimmers shower in their swimsuits for a few reasons. Perhaps it's because many natatorium facilities have open shower areas. Good luck convincing people to get fully naked and scrub below in open sight of others. Another reason is time and timing...why shower and get soaked, then try to put on a swimsuit? If you have never been a competitive swimmer, trust us, it's not a comfortable thing to do. It's far more practical to shower in a swimsuit then walk out on deck and get in the pool.
These two reasons alone mean that thorough showering prior to swimming may never be widely adopted, and that's just reality. But sure, in theory, showers are great! But for the sake of seeing this through, let's assume everyone showers thoroughly prior to jumping in the swimming pool. How much of a difference does it really make?
Swimmers contaminate pools while swimming
We do not disagree that showering before swimming is a good idea, but we question its impact. While contaminants on our bodies will certainly be reduced, showering before swimming does not mean RWIs would be prevented, or that chloramine production would be drastically reduced. Why? Because swimmers contaminate water when they are in it. Trust us, after many years of competitive swimming, we know this for a fact.
- Competitive swimmers sweat in the pool. Swim teams do not leisurely play in the swimming pool. They are there to train. Sports physiologists studied our swim team throughout the season and found that almost all of us were dehydrated, and many of us were severely dehydrated. It didn't seem to matter how much water we drank, by the end of practice, we were dehydrated again. There have been other studies that confirm our swim team was not alone. The conclusion? Swimmers sweat when training, but we don't feel it because we are in water. And we don't just sweat. We sweat a lot. So that begs the question: if swimmers sweat so much while swimming, what impact would a shower really have?
- Swimmers pee in the pool. Yes we know, it's gross. But let's not pretend swimmers don't know that already. There are valid reasons why swimmers pee in the pool, and we have written about it in the articles below. For starters, we have to be hydrated when we show up to swim, because we know we sweat so much. After all, swimmers are there to train, not to relax. Secondly, swim practices are almost always regulated to a certain time frame, and coaches maximize that time in the water. At the top of the hour, one group is climbing out while the next group is hopping in. Getting out in the middle of a two-hour swim practice is difficult, even if coaches build in bathroom breaks. In addition to the time crunch, getting out is cold. Evaporative cooling is a real thing, and even if the natatorium is 85ºF, going into an air conditioned bathroom can make your teeth chatter from being so cold. Why ruin that 30 minute warmup at the beginning of practice? Swimming culture will take time to evolve out of peeing in the pool, but for now, we must adapt to it. Again, theory vs. reality.
Alternatives to showering
In a perfect world, swimmers would shower thoroughly before going to the aquatic center in the first place. Then they could rinse off in the shower (wearing their swimsuits) prior to getting in the water, but it would not be nearly as important from an RWI prevention perspective. The thorough showering would have already been done at home. Swimmers would use the bathroom before getting into the pool, and take bathroom breaks throughout practice, if they could somehow not get cold in the process, and lose the momentum they had built up during the workout.
If all that occurs, the only contamination–in theory–is sweat and other body waste like mucous that would inevitably be introduced to the water by swimmers during their workout. These non-living organics can be handled by enzymes and secondary oxidation systems like ozone or AOP.
In reality, swimmers often head to afternoon practice after school and do not have time to go home first. Or, they get up early in the morning and are in the water before 6:00am, so why shower before that early morning practice? They will get to the pool and not want to get in (it's a swimmer thing).
Showering is out of the question for most of these swimmers, so we have to have systems and strategies in place to handle their contamination in the water. In reality, most of the contamination will be coming from them once they're in the water anyway, so showering is likely going to have a minimal impact in the first place.
Strategy one is enzymes. Enzymes devour bather waste, and break it down for easy removal, reducing the burden on chlorine. Enzymes do not directly remove nitrogen compounds like urea, but they can free up chlorine to have more residual to handle urea. That means urea can be oxidized by chlorine more rapidly and thoroughly, and that's a good thing. Enzymes do make a noticeable impact on indoor air quality, and are nice because they circulate throughout the pool alongside chlorine. Some examples of NSF-Certified swimming pool enzymes are:
- CV-600 or CV-700 by Orenda
- Amino Acid Digester (AAD) by NextGeneration Water Science, and
- SimplyPURE by Natural Pool Products.
Strategy two is secondary disinfection and oxidation. Ozone can both oxidize and disinfect, and UV can disinfect. these are helpful supplements to chlorine in its war against contaminants. While secondary systems are limited because they are point-of-contact systems, any water that passes through their area of treatment is going to be sanitized pretty thoroughly. If chlorine could do it all, secondary systems would not be necessary. So the very fact that these systems exist tells us that chlorine needs help.
Deck showers are a good, practical idea
While thorough scrubbing prior to swimming is unlikely to be widely adopted any time soon, there is something that would be more practical, and could help resolve the peeing in the pool issue too. Showers on the pool deck itself.
One such idea is to have a privacy wall where swimmers–in their swimsuits, of course–can walk behind and shower with warm, comfortable water. There, they can rinse off while already in the ambient natatorium, which will help them avoid getting too cold. These showers can be used before practice because the coach, lifeguards and staff can enforce it simply by being there. These showers are not meant for soap and water, nor to get naked. They are for rinsing off, and during practice, peeing. Hey, say what you will about it being gross to pee in the shower...but who can argue that it is worse than peeing in the pool? At least in the shower, the urine will not be oxidized and create more chloramines.
And even with these systems in place, indoor air quality can still be a burden without a properly designed dehumidification system and duct layout, complete with source-capture exhaust.
From an indoor air quality perspective, removing body oils and non-living organics like cosmetics are important, and can be accomplished with a quick rinse with soap. But even then, swimmers will produce more bather waste in the pool than they have on their bodies prior to jumping in (usually).
Showers can absolutely help, but we question how much impact that help actually makes. Sure, scrubbing to avoid recreational water illnesses (RWI) like crypto is a good benefit, but perhaps this is most important for those who have been sick and/or have had diarrhea recently. Does everyone need to do that? Probably not.
So rather than enforcing thorough showers prior to getting in, we suggest a more practical alternative is some showers on the pool deck with some moderate privacy, so that swimmers can use them on deck while wearing their swimsuits. In the pool itself, enzymes are an outstanding supplement to chlorine because they devour non-living organics and supplement chlorine. Secondary systems like ozone and UV also help, though they are limited in reach.
The purpose of this article is to look deeper into why all the experts seem to agree that showering is a must...and we conclude that it is not a "must". It is a nice thing to do, but at the end of the day, impractical and nearly impossible to enforce. We must instead find alternatives that will actually work.