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Swimming and gut health -

We therefore characterized fecal microbiota and serum metabolites in response to a 7-week, high-intensity training program and consumption of probiotic Bryndza cheese.

Fecal microbiota were categorized using specific primers targeting the V1—V3 region of 16S rDNA, and serum metabolites were characterized by NMR-spectroscopic analysis and by multivariate statistical analysis, Spearman rank correlations, and Random Forest models.

We found higher α-diversity, represented by the Shannon index value HITB-pre 5. However, Lactococcus spp. increased in both groups, with a higher effect in the Bryndza cheese consumers HITB-pre 0. Together, these data demonstrate a significant effect of high-intensity training HIT on both gut microbiota composition and serum energy metabolites.

Thus, the combination of intensive athletic training with the use of natural probiotics is beneficial because of the increase in the relative abundance of lactic acid bacteria.

The current study is a randomized controlled trial evaluating the effect of high-intensity training HIT on the bacterial composition in the gut of high-level swimmers. The study indicates that high-intensity swimming during the pre-competition period can increase bacterial diversity.

The positive effect of HIT on gut microbiota can be increased by regular consumption of natural probiotics. A healthy lifestyle and diet are key components of a healthy gut [ 1 ]. In addition, physical exercise itself brings benefits such as the enrichment of microflora diversity, the growth of beneficial bacteria, and the development of a commensal population [ 2 , 3 ].

Differences in the intestinal microbiome between athletes, obese subjects, and controls have been previously documented [ 4 , 5 ]. Athletic training with a characteristic structure in terms of volume and intensity of exercise leads to "healthier" intestinal microbiota [ 6 ].

High-intensity interval training HIIT brings beneficial changes in the gut microbiota in mice [ 7 , 8 ], previously inactive human adults [ 9 ], and healthy college students [ 10 ].

A significant association between changes in training structure over six weeks and bacterial composition has been reported in collegiate swimmers [ 11 ]. Interestingly, shorter lasting HIIT is reported to have no effect on the overall bacterial diversity or community structure of lean and overweight men [ 12 ] and women [ 13 ].

Changes in the abundance of several bacterial taxa can even be observed after a one-day extreme endurance event km mountain footrace [ 14 ]. However, the largest changes caused by a one-day event are related to metabolites short-chain fatty acids—SCFA produced by intestinal bacteria rather than to massive changes in microbiota structure.

In this regard, probiotics are a known and relatively well-studied intervention involved in the production of SCFA [ 16 ]. Moreover, the positive effects of dairy and non-dairy fermented foods and of lactic acid bacteria LAB on human health through the modulation of the gut microbiome are well documented [ 17 , 18 , 19 ].

We have recently reported the effect of traditional Slovakian fermented sheep cheese, among many probiotic foods, on the composition of gut microbiota [ 13 ].

Therefore, the purpose of this study was to compare the gut microbiome and metabolome of young swimmers before and after the completion of seven weeks of their pre-competition training program.

Based on our recent research with naturally fermented foods, one of our goals was to determine whether the consumption of probiotic Bryndza cheeses can bring additional benefits to the gut microbiome and metabolic variables [ 13 ].

The data were obtained in a longitudinal prospective study registered on ClinicalTrials. gov under No: NCT, conducted in Biomedical Research Center, in Bratislava, Slovakia.

The project was approved by the Ethics Committee of Bratislava Self-Governing Region No. This study was executed in conformity with the principles from the Declaration of Helsinki for experiments involving human beings.

After reading the written informed consent and after an explanation of the particular steps of the study and discussion with investigators, signed informed consent was obtained from all subjects before their participation in the study.

The athletes came from two swimming clubs. We randomly divided athletes into two groups, i. Exclusive criteria set to avoid skewed microbial data were as previously described [ 13 ]. Study subjects were asked to undergo 12 h of fasting and to avoid intensive exercise 24 h before examination.

Examination started in the morning at a. in the outpatient clinic of internal medicine and diabetes at the Institute of Clinical and Translational Research, Biomedical Research Center, Slovak Academy of Sciences, Bratislava.

Kyoto, Japan. Waist and hip circumference were also measured. The body mass index BMI was calculated. Blood pressure was measured via the arm during at least 5 min of rest OMRON. Blood was drawn in the fasting state into polyethylene tubes containing ethylenediaminetetraacetic acid EDTA as the anticoagulant and immediately cooled in ice or into polyethylene tubes without anticoagulant to obtain serum.

Participants had previously been instructed in the collection of specimens at home. Blood and fecal samples were collected twice: once before and once after the training period. All enrolled athletes from both the HIT and HITB groups completed a 7-week training program at the time of the season when the athletes were expected to be peaking for performance.

The last week ended with the Slovak Swimming National Championship over a long course pool 50 m in length. We instructed all athletes to follow their normal diet.

We additionally administered probiotic sheep cheese "Bryndza" to 12 athletes HITB at a frequency of 3—4 times a week and at a dose of 30 g for the entire 7 weeks of the training program. Samples of Bryndza were stored for microbial analysis when a new batch of cheese was received.

Bryndza is rich in natural probiotics and contains 13 families, 24 genera, and 44 species [ 21 ]. We report the structure of Bryndza microbiome in Additional file 1.

DNA was amplified by specific primers targeting the V1-V3 regions of 16SrDNA. Amplicons were used for the preparation of DNA libraries and sequenced using the Illumina MiSeq platform by bp pair-end reads Illumina, San Diego, CA, USA.

Details of this DNA sequencing procedure can be found in Hric et al [ 13 ]. Illumina Data Processing Adapters and low-quality read ends were removed using Geneious Biomatters, Ltd. The paired reads were merged set as paired reads , and the 3´ ends of reads were trimmed error probability limit: 0.

Microbial profiles of samples were assessed by comparison with RDP and the Silva database. Selected plasma metabolite concentrations were obtained using nuclear magnetic resonance NMR analysis as described in Hric et al. The concentrations of the following 20 plasma metabolites were analyzed by NMR: lactate, alanine, valine, leucine, isoleucine, glucose, acetate, 3-OH-butyrate, acetone, pyruvate, phenylalanine, tyrosine, glutamine, lysine, histidine, tryptophane, keto-leucine, keto-isoleucine, and ketovaline, and lipoprotein fractions containing fractions of VLDL, LDL, IDL, and HDL.

Serum OH vitamin D concentrations were determined with a chemiluminescent microparticle immunoassay CMIA; ARCHITECT OH vitamin D: Abbott Laboratories Diagnostics Division Abbott Park, IL USA diagnostic system in a certified hospital laboratory SYNLAB Bratislava, Slovakia.

The data were explored and analyzed by R ver. Exploratory data analysis involved the visualization of data by swarmplots overlaid with boxplots. Differences of values before and after treatment were normalized by the Inter-Quartile Range IQR to facilitate visual explorations of the data within the groups.

Gross outliers were excluded from the data usually 0 or 1 observation per variable. The null hypothesis of the zero mean difference was tested by the Welch t test. The p values were corrected for multiple hypothesis testing by the Benjamini Hochberg correction.

An analogous procedure was utilized for comparisons between groups, if the differences were not IQR-normalized. In each RF, the feature selection was performed by nested cross-validation, with the graph depth as the objective function.

Performance of RF with the selected features was assessed by the out-of-bag ROC curve and quantified by the Area under ROC AUC. Correlations between the characteristics of the gut microbiota and metabolism were analyzed using the Spearman correlation coefficient. The significance level of all statistical analyses was set at 0.

Power calculations for this study were based on our previous study of the effect of probiotic intake on Lactococcus abundance [ 13 ] by using an on-line calculator [ 27 ].

ClustVis was used to visualize multidimensional data by using principal component analysis PCA [ 28 ]. This training program undertaken during intervention was built on a previous training cycle and was characterized by a progressively increased volume and frequency of high exercise intensity.

High-intensity training consisted of swimming lengths of For swimming lengths of For 25 m lengths, we used 2 series with 16 repetitions on Wednesday. For 50 m lengths, we used 4—8 repetitions and for m 2—8 repetitions.

These latter training sessions most often fell on a Friday. The volume of training gradually decreased, and the number of repetitions in the main set increased from Phase1 to Phase 2A.

Phase 2A, high-intensity swimming, was followed by Phase 2B characterized by a taper during which training volume was exponentially reduced towards the Slovak Swimming National Championship over a long course. The detailed yardage and intensity distribution of the training undertaken by the athletes is presented in Table 1.

Eleven bacterial phyla were detected in the two groups: a high-intensity training HIT and b high-intensity training and use of probiotic cheese HITB. The highest percentages of abundance in the HIT group were seen for phyla Firmicutes In the group HITB, we observed predominantly the phyla Firmicutes We detected 62 families in two groups.

In the samples from subgroup HITB-pre, we detected 51 families, and in the subgroup HITB-post, 47 families. The subgroup HIT-pre included 41 families, and the HIT-post, 58 families.

The dominant family in both groups was the Lachnospiraceae HITB-pre— In all, genera were identified, of which genera were in group HITB HITB- pre; —HITB-post and genera in group HIT —HIT-pre; —HIT-post. The significant within-group differences in the relative abundance of bacterial populations are shown in Table 2 HITB and Table 3 HIT.

In the α-diversity analysis, we identified a significant increase of OTUs after both intervention programs HITB-pre Further, we detected a significant increase of the Shannon index value after both intervention programs HITB-pre 5. The value of the Simpson index did not differ between the groups.

α-diversity by Shannon index before and after intervention. a High-intensity training and use of probiotic cheese HITB ; b High-intensity training only HIT. Floating bars are the minimum to maximum values, the line shows the mean.

However, the genus Lactococcus increased after the HITB program fold, whereas in the HIT intervention, only a 5-fold elevation of relative abundance was seen.

We also found a few bacterial shifts in the relative abundance of bacteria producing SCFA metabolites. Selected bacterial genera enabled the discrimination of subjects from the pre and post HITB groups by using principal component analysis PCA Fig.

SVD with imputation was used to calculate principal components. Prediction ellipses are such that, with a probability of 0. HIT- pre variables before high-intensity training, HIT- post variables after high-intensity training.

There were no significant changes in blood parameters such as total cholesterol, insulin, or glucose after the interventions. After both interventions, we identified a significant increase of the vitamin D level HITB-pre We observed significant differences in the relative concentrations of certain metabolites after the interventions.

Moreover, after both programs, we identified significant differences in the concentrations of certain SCFA metabolites. Furthermore, the ML analysis with pyruvate, lactate, acetate, α-diversity Shannon index , and butyrate used as joint predictors led to an ROC curve with an AUC of 0.

FPR, false-positive rate; HIT, high-intensity training group; RFM-L, Random Forest machine-learning; TPR, true positive rate. FPR, false-positive rate; HITB, high-intensity training and use of probiotic cheese group; RFM-L, Random Forest machine-learning; TPR, true positive rate.

The reported controlled trial was used to study the effect of 7 weeks of a high-intensity exercise program, with or without probiotic Bryndza cheese consumption, on the gut microbiota composition and metabolomics in high-level competitive swimmers.

We hypothesized that intensive physical training would have a positive influence on SCFA producers in the gut and on metabolites in the blood of athletes.

We expected that regular consumption of Bryndza cheese would have an additional positive effect on the relative abundance of lactic acid bacteria LAB. Our main findings demonstrated that high-intensity exercise increased bacterial diversity as measured by the Shannon index in both groups. Furthermore, we found a higher abundance of the LAB after Bryndza consumption Lactobacillales and Lactococcus.

Remarkably, we observed a higher relative abundance of intestinal SCFA producers. In addition, we found a decrease in serum butyrate and acetate in both groups. Effects of athletic training and physical fitness on increased microbial diversity has been widely published based on human and animal models [ 3 , 14 , 29 , 30 , 31 , 32 ].

However, the reported results related to α-diversity differ. In our recently published study, we reported no higher α-diversity in elderly athletes compared with controls, despite lifelong systematic endurance training and higher cardiorespiratory fitness [ 4 ].

Similarly, Allen et al. Moreover, Resende et al. At first glance, our results are not in agreement with a previous study undertaken on collegiate swimmers [ 11 ]. Hampton-Marcell et al. They reported a decline of training volume at the final phase last 2 weeks with an average yardage of However, the swimmers in our study covered, during the last two weeks before competition, on average a weekly yardage that was twice as long as that reported in the study of Hampton-Marcell et al.

We assume that the length of training program and the intensity explain the controversy related to the effects of physical exercise on α-diversity. Whereas short-lasting HIT 3—4 weeks had no effect on the overall bacterial diversity of lean and overweight men [ 12 ] and women [ 13 ], a longer intervention in animal models improved gut microbial diversity [ 7 , 8 ].

The largest intestinal changes induced by physical training concern both the increase in number of SCFA producers and the production of energetic metabolites e. As found in professional international rugby union players, microbial-derived SCFAs including acetate, propionate, and butyrate and metabolic pathways are enhanced in the athletes relative to controls [ 32 ].

We have however observed only a few changes related to the types of butyrate producers. Here, we report the increase in the relative abundance of the genus Butyricimonas spp. and of Alistipes spp. at the end of the training period.

Concomitantly, we have also noticed decreases in serum metabolites acetate, butyrate. Ketone oxidation e. However, βHB oxidation contributes minimally to energy expenditure, although the large relative contribution of exogenous βHB oxidation occurs during light exercise [ 36 ].

The results from trained cyclists suggest that the pre-training ingestion of βHB has no benefit for endurance performance [ 38 , 39 ]. The acute exogenous intake of ketone ester can even slightly impair short high-intensity endurance exercise performance [ 40 ].

The production of ketone bodies, while providing an alternative substrate for oxidative phosphorylation, actually decreases muscle glycolysis and plasma lactate concentrations [ 35 ]. Here, we report an increased intensity of exercise accompanied by a higher rate of anaerobic glycolysis during the peak period.

This might explain the higher baseline pyruvate and lactate as a consequence of muscle adaptation to an exhaustive training period. As observed previously, baseline serum pyruvate is increased in response to a period of high-intensity interval training [ 41 ]. Additionally, we consider that the reported changes in serum metabolites, namely in acetate, butyrate, lactate, and pyruvate, are the result of skeletal muscle metabolism rather than of the metabolism of gut microbiota.

An additional purpose of the study was to find out whether high-intensity exercise training combined with Bryndza sheep cheese consumption can change the relative abundance of LAB in the collected stools of athletes. Similarly to Pangallo [ 42 ], we report that, among other LAB, the incidence was highest of the genus Lactococcus spp.

After 7 weeks of intervention with Bryndza consumption, the athletes exhibited an increased relative abundance of Lactococcus spp.

However, we also report higher Lactococcus spp. in swimmers who have not consumed Bryndza. This can be explained by the seasonal variation of vitamin D that has been previously positively associated with Lactococcus spp. In confirmation of this idea, we have found a positive association between the relative abundance of Lactococcus spp.

and vitamin D in the blood. At the beginning of the study end of April , both groups of swimmers were deficient in vitamin D [ 45 ], perhaps because of the lack of vitamin D synthesis from the low levels of sunlight during the winter months. Subsequently, lighter clothing and exposure of more of the body to sunlight probably increased vitamin D synthesis, as indicated by our reported elevated concentration of vitamin D in blood by the end of June.

Remarkably, the Lactococcus spp. in the Bryndza group increased fold, whereas in the group without Bryndza intervention, we observed "only" a 5-fold positive change in relative abundance. The RF and ML analyses have identified pyruvate, acetate, butyrate, and α-diversity Shannon index as suitable joint predictors with a fair HIT and excellent HITB ability to discriminate between subjects pre- and post-intervention.

Furthermore, the GraphDepth analyses ranked pyruvate, lactate, and acetate as the three best-discriminating factors for the subjects within the HITB group, and acetate, pyruvate, Butyricimonas and butyrate as the four best-discriminating factors for the subjects within the HIT group.

Further, we did not measured stool metabolites and therefore were unable to confirm the effects of any significant increase of intestinal SCFA producers at the end of the training period. In particular, the relative rather than absolute concentrations of metabolites is a limitation of the study.

Moreover, the distribution of men and female subjects and effects of the menstrual cycle might have influenced our results. Despite non-significant changes of body weight during intervention, we might have missed alterations in body fat and fat-free mass percentage.

The athletes were from two different swimming clubs and were trained by two coaches. Although the coaches worked closely together and planned the training for this study, we admit that each coach has their own signature. Finally, our study participants were all swimmers, and so the results of our study cannot be translated to other high-level athletes in general.

A remarkable strength of our investigation is that the cohort of experienced high-level athletes shared the same training program, freedom from non-communicable disease, and being medication naïve.

The identification of suitable joint predictors with a fair HIT and excellent HITB ability to discriminate between subjects pre- and post-intervention by Random Forest machine learning algorithm strengthens our analysis and distinguishes the intervention effect between HIT and HITB.

The pre-competition training program characterized by an increased volume of high-intensity exercise improved intestinal α-diversity independently from the consumption of a natural probiotic.

Serum metabolites lactate, pyruvate, acetate, and butyrate reflect the structure of the training period with an emphasis on anaerobic metabolism. Bryndza cheese consumption in combination with intensive athletic training brings additional probiotic benefits by increasing the amount of LAB.

The data presented in the study are deposited in the GenBank repository with BioProject accession number SAMN - SAMN, Bioproject PRJNA Redondo-Useros N, Nova E, González-Zancada N, Díaz LE, Gómez-Martínez S, Marcos A. Microbiota and lifestyle: a special focus on diet.

Article CAS Google Scholar. Dorelli B, Gallè F, De Vito C, Duranti G, Iachini M, Zaccarin M, et al. Can physical activity influence human gut microbiota composition independently of diet?

A systematic review. Monda V, Villano I, Messina A, Valenzano A, Esposito T, Moscatelli F, et al. Exercise modifies the gut microbiota with positive health effects.

Oxid Med Cell Longev. Article Google Scholar. Šoltys K, Lendvorský L, Hric I, Baranovičová E, Penesová A, Mikula I, et al. Strenuous physical training, physical fitness, body composition and bacteroides to prevotella ratio in the gut of elderly athletes.

Front Physiol. Exercise and associated dietary extremes impact on gut microbial diversity. Mohr AE, Jäger R, Carpenter KC, Kerksick CM, Purpura M, Townsend JR, et al. The athletic gut microbiota. J Int Soc Sports Nutr. Denou E, Marcinko K, Surette MG, Steinberg GR, Schertzer JD.

High-intensity exercise training increases the diversity and metabolic capacity of the mouse distal gut microbiota during diet-induced obesity. Am J Physiol Endocrinol Metab. Wang G, Zhou H, Zhang L, Li R, Luo L, Yu Z, et al.

J Physiol Biochem Spain. Warbeck C, Dowd AJ, Kronlund L, Parmar C, Daun JT, Wytsma-Fisher K, et al. Feasibility and effects on the gut microbiota of a week high-intensity interval training plus lifestyle education intervention on inactive adults with celiac disease.

Appl Physiol Nutr Metab Physiol Appl Nutr Metab. Donati Zeppa S, Amatori S, Sisti D, Gervasi M, Agostini D, Piccoli G, et al.

Nine weeks of high-intensity indoor cycling training induced changes in the microbiota composition in non-athlete healthy male college students. Article PubMed PubMed Central Google Scholar. Hampton-Marcell JT, Eshoo TW, Cook MD, Gilbert JA, Horswill CA, Poretsky R. Comparative analysis of gut microbiota following changes in training volume among swimmers.

Int J Sports Med. Rettedal EA, Cree JME, Adams SE, MacRae C, Skidmore PM, Cameron-Smith D, et al. Short-term high intensity interval training HIIT exercise does not affect gut bacterial community diversity or composition of lean and overweight men.

But exactly what's the best way to do that? Try one of the following eight low-impact yet highly effective! exercises--and remember to continue to support your gut health efforts by eating healthy, drinking plenty of water, and taking a daily probiotic supplement.

Yoga Yoga has a well-earned reputation for helping people slim down, tone up and get healthier while being gentle on the body, making it an excellent option for those looking to reduce stress and improve gut health. What's more, there's a significant body of research to back up yoga's particular benefits for digestive health.

One study found that those with inflammatory bowel disease experienced fewer symptoms when following an exercise regime that included an hour of yoga a day. Additional research has shown that the gut health promoting effects of yoga work equally well for children and adolescents with irritable bowel syndrome.

In other words, spring for a group package at the local yoga studio, as the entire family can benefit from taking a yoga class or two! Jogging One of the exercises that the University of Illinois' study participants could choose was jogging--and as the results of that study show, jogging is an excellent choice for those looking to bolster the diversity of their gut microbiome.

Whether indoors on a treadmill or outside on a trail, a steady jog can dramatically improve your health. The key as with all exercises on this list is to work hard enough to break a sweat but not so hard that you overstress your body.

Walking It can be easy to dismiss walking as an effective exercise routine. In the age of high-intensity workouts, walking just doesn't seem painful enough to work. In actually, walking is one of the best exercises you can do: it's extremely low-impact, it's an excellent starting point for those that are new to exercise, and you don't need any equipment to get started.

As with yoga, walking has been shown in studies to help those suffering from poor gut health; study participants with irritable bowel syndrome experienced a significant drop in their gastrointestinal symptoms after taking up walking for six months.

So put a pair of comfortable shoes on and get yourself out the door--just make sure that you're walking fast enough to get that heart rate up Swimming Perhaps the ultimate in low-impact exercises, swimming is a particularly good choice for those who want to improve gut health while also protecting joint health.

One caveat here: spending too much time in heavily-chlorinated pools like most public pools are can be counterproductive in terms of gut health, as the high levels of chlorine may have an effect on the good bacteria in your gut as well as the bad bacteria that can grow in pools.

To the extent possible, trying swimming in fresh water. Hey, it's the perfect excuse for a trip to the beach! Cycling On the road or in the gym, cycling is another great option for digestive health.

Research has shown that low- to moderate-intensity cycling done for approximately three hours a week can increase the good bacteria in the gut particularly Akkermansia while lowering the number of bad strains such as Proteobacteria. Elliptical Like walking, jogging, and cycling, using the elliptical machine was one of the options offered to the University of Illinois' study participants, proving its effectiveness at promoting gut health.

The biggest benefit of using an elliptical machine over the other three exercises is that it lowers the amount of weight that the lower body must bear, making it better for those with chronic lower-body injuries.

Tai Chi This low-impact, gentle exercise has been used in China for centuries to treat many health issues, including digestive tract problems. The slow and focused movements of Tai Chi center around the spine, meaning that the digestive organs can also benefit from the strengthening and toning effects of these circular motions.

Many who practice Tai Chi note that it helps promote regular digestion and relieve constipation. Pilates Similar to yoga, Pilates focuses on balance, posture, and flexibility, making it an excellent low-stress workout option.

As an added bonus, several common Pilates moves--such as cat-cow and articulated bridge--work the muscles of the deep core in such a way as to promote proper digestion.

Choose Your Exercise Plan Keep in mind that the particular exercise routine that you choose is less important than choosing one that you can keep up. Remember the University of Illinois study that we talked about above? After embarking on a workout routine for six weeks and seeing their gut health improve, participants were directed to return to their sedentary lifestyle for another six weeks.

Perhaps unsurprisingly, their gut microbiomes also returned to their previous unbalanced, unhealthy state. The conclusion here is clear: exercise needs to be a regular habit to truly affect any meaningful change in your gut health. So lace up your sneakers, hit the gym and--of course!

November 3, Diet , Digestive health , Women.

Adn pools, swimming and gut health, lakes, rivers, or oceans are all swimming and gut health swimmimg of water recreation illness. Recreational water hwalth typically affect a Pomegranate cultivation tips stomach and intestines, skin, or respiratory system. If you think you have a recreational water illness that needs medical attention, contact your health care provider. Report suspected recreational water illnesses to your local health department. If you can't reach them, contact us at hour assistance available.

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Department of Health - Healthy Swimming Swimming and gut health college swim teams learned a stomach-churning Creatine and cognitive function the hard way during a recent series of meets: regardless of skill heqlth speed, the real winner of the swimmjng will always be the heqlth swimming and gut health that swjmming the pool. Guy also highlighted "an swimminf need to Rehabilitation and recovery swimming and gut health swimming, including recommendations bealth persons not to swimning if they have but and to avoid swallowing swimming pool water to prevent waterborne disease," the authors of a case report on the investigation wrote. The report, led by health officials in Massachusetts, was published Thursday in the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report. It all began earlier this year when competitive swimmers from a Massachusetts-based college went to Puerto Rico for a weeklong training session. While there, the swimmers plunged into a training pool, a waterfall, and the ocean. It's unclear where they picked up the gruesome gut crasher exactly, but three days after their return, the swimmers' health started dipping. By the end, 19 of 50 swim team members of the men's and women's teams would fall ill.