Effect of 2000-meter rowing test on parameters of intestinal integrity in elite rowers during competitive phase - observational study.

doi:10.21203/rs.3.rs-3857078/v1

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Effect of 2000-meter rowing test on parameters of intestinal integrity in elite rowers during competitive phase - observational study.

https://doi.org/10.21203/rs.3.rs-3857078/v1

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The epithelial wall leakage has been extensively studied in sports disciplines like running and cycling. However, little is known about gut permeability in other disciplines, like rowing, especially after the regular competition performance distance of 2000 meters. Therefore, our study aimed to check gut permeability after the 2000-meter rowing test in the annual training cycle. The study was performed at the beginning of a competitive training phase. Eighteen elite rowers of the Polish Rowing Team participated in study after applying the inclusion/exclusion criteria. The participants performed a 2000-meter ergometer test. Blood samples were taken before the test, after exercise, and after 1-hour of restitution. Parameters, such as I-FABP, LPS, LBP, and zonulin, were determined using appropriate biochemical tests. There were no changes between pre- and post-exercise values in I-FABP, LBP, LPS, and zonulin. However, the I-FABP changed from 6,49 ± 2,15 to 8,3 ± 2,71 (ng/ml) during the recovery period, and LBP decreased from 2,73 ± 0,77 to 2,035 ± 0,53 (µg/ml) simultaneously. Other parameters have not changed. The results of this study showed that intense physical effort performed during the training period is sufficient to negatively affect the gut integrity of rowers.

Health sciences/Signs and symptoms/Digestive signs and symptoms

Biological sciences/Immunology/Mucosal immunology

Exercise–associated symptoms are common among endurance athletes, and they may lead to minor discomfort or cause symptoms of clinical significance¹. The prevalence of exercise-induced gastrointestinal symptoms among elite endurance athletes was reported to be 70%². Moreover, they are arguably the leading cause of poor performance in competition³. Additionally, they may cause of variety of gastrointestinal tract symptoms such as abdominal pain, bloating, the urge to regurgitate, and nausea⁴.

The two main pathways may be responsible for exercise-induced gastrointestinal syndrome. The first pathway is connected to the redistribution of blood flow and splanchnic hypoperfusion. In this case, the circulatory-gastrointestinal path diverts blood flow to working muscles and peripheral circulation, reducing total visceral perfusion. The second neuroendocrine-gastrointestinal is connected to stress hormones and results in increased sympathetic activation and concomitant reduction in the functional capacity of the gut. Both pathways may lead to mucosal erosion and damage to the particular cells.

As a consequence, gut permeability of the lumen for toxins and bacteria may increase, allowing them to enter the systemic circulation (endotoxemia), burdening the immune system^1,4. In addition, there is a potential third pathway that may strongly influence the gut barrier – mechanical strain: jarring, jolting, position, and friction¹. Moreover, many stressors, such as heat stress, certain medications, and oxidative stress, disrupt gut function and the integrity of the gastrointestinal tract⁵. As a result, gastrointestinal functions, such as motility, digestion, and absorption, may be decreased¹. The established term “exercise-induced gastrointestinal syndrome” (EIGS) refers to these primary causes and secondary outcomes that naturally arise with the onset and ongoing exercise¹. Systematic reviews ^4,6 emphasizes that the duration of exercise protocol should last at least 1 hour to cause intestinal damage^1,4,6. However, it has been shown that vigorous exercise that lasted not even 10 minutes has significantly increased intestinal permeability⁷. Gut permeability was also influenced by protocols of running − 20 minutes at 80% VO2 max (maximal oxygen uptake) ^8,9. Therefore, a fraction of the anaerobic threshold has been pointed out as a more predictive indicator of gastrointestinal permeability than a fraction of VO2 max, which emphasizes the type of exercise performed does not have as much impact as its intensity¹⁰.

Well-trained rowing competitors cover a distance of 2000 meters in about 6 minutes, reaching the average concentration of lactic acid above 10 mmol/L ^11,12. Over many years of cooperation with the national team, we have noticed that gastrointestinal disorders occur in 6/24 rowers, which they describe as severe (unpublished data). So far, we have observed increased inflammatory cytokines and reactive oxygen species after the 2000-meter ergometer test^11,12. We suspect the above-mentioned changes are accompanied by intestinal damage an increase in their permeability. Additionally, we suspect that the rower's repetitive movements and posture during exercise may strongly influence intestinal damage.

For this reason, we decided to conduct a study that stimulates a rower's race over a typical distance of 2000 m on a rowing ergometer. We hypothesize that although the time of exercise is short, applying a high load effort will result in gut permeability. Therefore, to determine the presence of intestinal permeability, level of intoxication, and inflammation, markers specific to these changes have been used, such as I-FABP (Intestinal Fatty Acid Binding Protein), zonulin, LPS (Lipopolysaccharide), LBP (lipopolysaccharide-binding protein).Thus, the study aims to check the influence of the 2000m maximal test performed on an ergometer on the gut permeability of the rower.

Participants

The 2000-meter test on an ergometer is very demanding for a competitor; in addition, 22 rowers have started the test, but only 18 have finished it (one was ill, one refused to row during the race, two couldn't row at this pace) (Table 1).

Table 1

Essential characteristics of study participants (N = 18).
	Height [cm]	Weight [kg]	Age [years]	Water [%]	Body fat [%]	Lean body mass [kg]	Training experience [years]
Mean	192,0	89,4	20,3	64,4	9,8	81,0	6,7
SD	4,1	5,8	1,2	2,5	3,0	3,8	1,2

Table 1. - Insert

Dietary intake

The energy intake was 4352 ± 505 kcal, protein intake was approximated at ~ 2,0 g/kg body mass, and fat ~ 1,7 g/kg body mass (Table 2). There was, also negative correlations between carbohydrates and zonulin (r = − 0,763, p = 0,006).

Table 2

Dietary intake.
	Energy [Kcal]	Protein[g]	Fat [g]	Carbohydrates [g]	Fiber [g]
Mean	4352,55	181,45	155,56	584,27	33,97
SD	505,29	41,61	34,78	96,31	7,57

Table 2. -Insert

2000-meters rowing test

The average test time was 6:07:43 ± 0:07:13, and the mean power output was 453,83 ± 26,45 [Wat]. There was a significant increase in lactate levels observed before and after the exercise test (Fig. 1) (p < 0.0001, Cohen`s d = 8,37). There was no correlation between LA and any other markers.

Figure 1. - Insert

Markers of gut permeability and inflammation

There were no changes in I-FABP levels after the exercise test and between baseline and recovery (Fig. 2). However, after 1 hour, values increased significantly from 6,49 ± 2,15 to 8,3 ± 2,71 (ng/ml) during the recovery period (p = 0,03, Cohen`s d = 0,75). There were no changes in LBP level values after exercise and between baseline and recovery, but there was a significant decrease in 1-hour recovery time from 2,73 ± 0,77 to 2,035 ± 0,53 (µg/ml) (p = 0,045, Cohen`s d = 1,07). The same pattern occurred at the LPS level, but changes have not reached a significant difference. Zonulin level has not changed in all time points. There were also positive correlations between I-FABP and zonulin (r = 0,271, p = 0,048) and another between LBP and LPS (r = 0,331, p = 0,014).

Figure 2. Insert

This study aimed to assess the impact of intense exercise tests at the beginning of the competition season on markers of intestinal permeability in competitive elite rowers. As far as we know, this is the first study on rowers in the context of gut permeability and was conducted in their annual training cycle. For rowers, 2000-meter tests take place periodically, without any breaks from regular training, and are a certain stage summarizing the training. A 2,000-m time trial is a standard test used to assess performance in rowers¹⁵. We chose the competitive phase because, in this phase, athletes experience strong physiological stresses which is reflected in the increase in biomarkers of tissue damage and immune cell activation¹⁶.

We observed a significant increase in I-FABP levels after the 2000-meter rowing ergometer test. I-FABP is a marker found on the upper luminal surface of the endothelial cell, and its increase reflects endothelial cell injury⁶. It is a sensitive biomarker for early gut damage¹⁷. Significant changes concern the time between the post-exercise and recovery period (1 hour after), probably due to the low time of exercise (6 minutes); changes may not have occurred precisely after the end of the ergometer test but are shown 1 hour after the recovery. Recent reviews show that at least 2 hours of exercise is needed to disturb the epithelial wall^1,4,6. Still, our results suggest that even a short exercise of very high intensity may increase epithelial injury. The obtained results may indicate that not only the duration of physical activity but also the intensity is a factor that violates the integrity of the intestinal barrier. Edwards et al. suggest that exercise intensity may be a more decisive factor causing loss of intestinal integrity than exercise mode ¹⁰. Nevertheless, McKenna et al. highlights the exercise duration as a factor influencing intestinal barrier injury ¹⁸, which is needed to obtain clinical relevance of the I-FABP increase (~ 1000pg/ml) ⁴. Our study's average increase in I-FABP was Δ = 1,81 ng/ml (1810 pg/ml). This response is higher than obtained after 60 minutes at 70% of the maximum workload capacity ¹⁹, or a 20-minute run at a constant speed equivalent to 80% O_2peak ²⁰. Moreover, running at 78% VO2 max (4 mmol/L blood lactate) until T_c increases by 2.0°C or volitional exhaustion Δ also gave lower results ²¹. Even a prolonged exercise protocol consisting of 15 minutes cycling at 50% HRR + 60 minutes running + 15 minutes cycling at 50% HRR at 30°C increased I-FABP Δ = 806 pg/ml. Our outcome increase was comparable to 2-hour running at 60% VO2 max Δ = 1230 pg/ml ²². Though there were no significant changes in zonulin levels after exercise, and the response was strongly individual, there was a positive correlation between I-FABP and zonulin, a marker implicated in regulating mucosal permeability and capable of reversible tight junction disassembly²³. The correlation observed in our study suggests that as the epithelial injury increased, so did the tight junction leakage. These phenomena may give rise to direct consequences, such as alterations to the enteric nervous system and/or enteroendocrine cells, or indirect repercussions, including disruptions to gastrointestinal motility, such as nutrient malabsorption⁴. The main feature of splanchnic hypoperfusion is intestinal ischaemia ^24,25. In fact, Rehrer et al. reported a decrease in portal blood flow (20%) within the first 10 minutes of running at 70% of the maximal oxygen update ²⁶. Furthermore, 1 hour of cycling at 70% of maximal wattage out- put (Wmax) resulted in increased splanchnic ischemia, with the most pronounced increase occurring within the first 10 minutes of exercise ²⁴ The resultant intense ischemic conditions contribute to epithelial injury, causing erosion across all epithelial cell types and subsequently augmenting intestinal permeability. Remarkably, our study aligns with this temporal pattern, indicating that the initial 10 minutes of exercise may represent a critical period for the onset of intestinal damage.

The second pathway that may lead to increased I-FABP is mechanical strain related to either mechanical work performed by the athlete's body during performance. For example, reflux was more common among runners than cyclists ². It is found to be a result of the repetitive high-impact mechanics of running ³. In rowing, we also have repetitive movements that may influence the gut barrier. Posture can also affect gastrointestinal symptoms in rowers. Similar to cycling, where the cycling position can cause upper gastrointestinal symptoms due to increased pressure on the abdomen. Both splanchnic hypoperfusion during exercise ¹⁹ and specific mechanical movements during rowing may have influenced the gut barrier of the rower, and the increase in both parameters suggests increasing gut permeability.

Lipopolysaccharide binding protein is mainly synthesized in hepatocytes and epithelial cells ²⁷, and it is considered a stable indirect marker of exposure to bacterial endotoxins ²⁸. Surprisingly, we observed a decrease in LBP levels after a 1-hour recovery period, without significant changes in LPS levels, but there was a positive correlation between both parameters. Obtained results in our research are against other authors', where LBP increased after exercise ^7,18,29 or stayed at the same level ^30,31. However, an LBP decrease was observed after a 3-hour run ³². Under conditions of intense physical exertion, LBP may migrate and be transported into cellular compartments ³², which may appear in our study.

Moreover, LBP concentration may be connected to the LBP utilization overwhelming the replacement capacity ³². It is not entirely known why the decreased levels of LBP after exercise may occur. Observed in our study, LBP decrease probably was associated with the physical exertion of rowers during the 2000-meter ergometer test and connected to both migration into cellular compartments and overwhelmed replacement capacity.

Remarkably, our observations revealed a negative correlation between zonulin levels and carbohydrate intake. This finding aligns with the results reported by Etxebarria et al., where carbohydrate intake 24 hours before exercise demonstrated an association with reduced lipopolysaccharide translocation³³. Notably, a judicious carbohydrate intake in the 24 hours preceding exercise may contribute to mitigated gut permeability. These findings underscore the potential impact of dietary choices on modulating biomarkers associated with gut health, emphasizing the significance of pre-exercise nutritional strategies in influencing gastrointestinal outcomes.

An intensive 2000-meter ergometer test simulates the start of a rower in a competition. This is the only starting distance for the male rowers. Therefore, constantly high levels of gut permeability markers and their increase even after an hour of recovery may predispose the rower to GIS symptoms. Consequently, athletes are exposed to worsening start results, extending the recovery time and, in extreme cases, exclusion from the competition. Therefore, nutritional strategies and supplementation can be crucial in keeping an athlete in full shape.

The intensive 2000-meter ergometer test performed by highly qualified rowers caused changes in observed parameters. Increased I-FABP levels, correlating with increased zonulin levels, may suggest that gut permeability has occurred due to both enterocyte damage and thigh junction disconnection. Moreover, the effect of the training loads and performed test may be responsible for the observed decrease in LBP levels accompanied by a reduction in LPS levels in the recovery period. It may be caused by the connected migration of LBP into cellular compartments and overwhelmed replacement capacity. The results of this study showed that intense physical effort performed during the training period is sufficient to affect the gut permeability of rowers negatively.

Study limitations

The present study acknowledges certain limitations, foremost among them being the relatively small sample size. Conducting research within the domain of elite sports poses challenges in assembling a cohort of highly trained athletes with comparable performance levels and training regimens. Furthermore, a more comprehensive exploration of inflammatory markers in subsequent studies is imperative to gain a thorough understanding of the observed changes. Another limitation stems from the absence of individualized breakfast analyses; however, it is noteworthy that the breakfast was standardized to meet energy and macronutrient requirements. Future investigations would benefit from incorporating detailed information on standardized meals into their protocols for a more nuanced analysis of nutritional influences.

The study was conducted in July 2022 during an athlete`s camp in a yearly training cycle's competitive phase.

Participants

Eighteen male National Polish Rowing Team members (heavy-weight rowers) participated in this study. Before the exercise test, the anthropometric parameters were assessed using an electronic scale to the nearest 0,05 kg (Tanita BC 418 MA Tanita Corporation, Tokyo, Japan). Results are presented in Table 1. The study was conducted following the Declaration of Helsinki, and its protocol was approved by the local Ethics Committee at Poznań University of Medical Sciences (decision no. 314/22 in 2022). All participants received an explanation of the study procedures and gave their written, informed consent to participate. Representative study population - the sample size was calculated using a G-power program ¹³, assuming 0.05 as the alpha level, 0,75 as the effect size (data from our study – not published yet = 0,75, and meta-analysis = 0,81 ⁶, and 0.9 power. The minimum sample size was estimated at 16 participants. However, we recruited all rowing team members that met the inclusion/exclusion criteria.

Inclusion criteria. Minimum five years of training, five training sessions per week minimum, total training time minimum of 240 minutes, membership in Polish Rowing Team, finishing 2000-meter ergometer test.

Exclusion criteria. Antibiotic therapy, probiotics, prebiotics within the last three months, dietary regime, and gastrointestinal diseases.

Rowing test

The exercise test was performed at the beginning of a competitive phase of the annual training cycle characterized by high volume and training loads. After baseline blood samples were taken, participants reported to the exercise laboratory after a light breakfast and performed a controlled 2000-meter ergometer test (Concept II, USA). Furthermore, each subject had to finish the distance in the shortest time possible because test results were considered during the selection to the championship team; for that reason, athletes were incredibly motivated to perform test at maximal effort. Before the trial, subjects performed a 5-minute individual warm-up.

Training program during sports camp

The characteristics of a training profile, such as intensity, volume (measured in minutes), and type (specific, i.e., rowing: endurance, technical, speed, etc., and nonspecific: strength, jogging), were recorded daily. The intensity of the training was classified concerning the lactic acid (LA) threshold (4 mmol/L) as an extensive (below the LA threshold) or intensive (above the LA threshold) workload (Table 3). All national team players must comply with the training regime based on the training plan.

Table 3

Training schedule during the week preceding blood sample collection before the Test.
Days before Trial	1	3	4	5	6	7	8
Time rowed, min/day	90	70	120	160	80	90	T E S T
Distance rowed, km/day	20	12	22	36	18	20
Training for force development, min/day	0	0	0	0	0	0
Extensive endurance rowing training time, min/day	64	70	120	136	80	90
Very high intensity endurance rowing training time, min/day	26	0	0	24	0	0
Unspecific training (running, etc.), min/day	90	10	30	20	10	10
Total training time, min/day	180	80	150	180	90	100

Table 3.

Food intake

The total dietary intake was analyzed due to the 24-hour dietary recall method by a dietitian, who was available for participants during all meals. Then, the amount of energy, protein, fat, carbohydrates, and fiber was measured through a commercially available program called DietetykPro (Producer DieteykPro Wrocław, Poland). The above parameters were chosen because they strongly influence the intestinal microbiota, especially carbohydrate, protein and fiber ¹⁴. The subjects used the same canteen where recipes for individual dishes were available, facilitating the quantitative and qualitative consumption assessment. The investigation focused on food consumption within the 24 hours preceding the test, acknowledging that the gut microbiome exhibits maximal variability during this temporal window.

Blood sampling and analyses

Blood samples were gained from the antecubital vein before the 2000-meter test (in the morning after an overnight fast), one minute after completion, and after a 1-hour recovery period. The samples were centrifuged after obtaining them to separate serum from blood cells. The serum was frozen immediately and stored at − 80°C until testing. In addition, capillary blood samples were obtained from the earlobe before and immediately after the exercise test to assess the athletes’ lactic acid levels.

Serum I-FABP, LPS, LBP, and zonulin were measured using commercially available enzyme-linked immunosorbent assays (ELISA; SunRed Biotechnology Company) with an assay range of 0,3–80ng/ml for I-FABP, 12–4000 EU/l for LPS, 0,2–60µg/ml LBP, and 0,25–70 ng/ml for zonulin. Lactate concentration (La) in capillary blood was checked immediately after sampling using a commercially available kit (Diaglobal, Berlin, Germany); lactate concentrations were defined in mmol/L.

Statistical analyses

GraphPad Prism 9 (GraphPad Software, Boston, USA) performed statistical analyses and graphics. Descriptive statistics, such as mean and SD, were used to visualize immediate trends and patterns for three-time points. Shapiro–Wilk test was used to check the normal distribution of variables. The Brown-Forsythe test was used to measure the equality of variances. One-way analysis of variance with repeated measures (ANOVA), with Tukey's posthoc analysis, was used to assess differences in measured variables of the three-time points (pre-exercise, post-exercise, and 1 h recovery), respectively. Zonulin level was not normally distributed, and the Friedman test was used. The t-test was used for La because there were only two-time points. For the effect size measure, Cohen`s d was calculated. Using Cohen`s criteria, the effect size was interpreted as small (0.2), moderate (0.5), and large (0.8) (Cohen, 1988). For correlation analysis, Pearson’s coefficient of linear correlation was calculated. The level of significance was for all tests at p ≤ 0.05 level. There was no missing data.

EIGS - exercise-induced gastrointestinal syndrome

ELISA - enzyme-linked immunosorbent assays

HRR – heart rate recovery

HSP - heat shock proteins

I-FABP – intestinal fatty acid binding protein

La – lactic acid

LBP – lipopolysaccharide-binding protein

LPS - lipopolysaccharide

MNC - mononuclear cells

ROUT - method combines robust regression and outlier removal

STROBE - Strengthening the Reporting of Observational Studies in Epidemiology

TLR – toll-like receptors

TNF-alfa – tumor necrosis factor alfa

VO2max - maximal oxygen uptake

Acknowledgments

Not applicable

Author Contributions: H.D. and ASS conceived and planned the experiment. A.K., JCW, and JOK carried out laboratory analysis. H.D. contributed to the statistical analysis and took the lead in writing the manuscript with consultation with ASS, HD, PB collected the data, HD visualization, ASS and HD project administration. All authors have read and agreed to the published version of the manuscript.

Availability of data and materials

Due to ethical concerns, the datasets generated and/or analyzed during the current study supporting data cannot be made openly available. However, they are available from the corresponding author upon reasonable request.

Consent for publication

Not applicable

Competing interests

Not applicable

Conflict of interest

The authors have no competing interests to declare relevant to this article's content.

Costa, R. J. S. et al. Assessment of Exercise-Associated Gastrointestinal Perturbations in Research and Practical Settings: Methodological Concerns and Recommendations for Best Practice. Int. J. Sport Nutr. Exerc. Metab. 32, 387–418 (2022).
Peters, H. P. et al. Gastrointestinal symptoms in long-distance runners, cyclists, and triathletes: prevalence, medication, and etiology. Am. J. Gastroenterol. 94, 1570–1581 (1999).
de Oliveira, E. P., Burini, R. C. & Jeukendrup, A. Gastrointestinal complaints during exercise: prevalence, etiology, and nutritional recommendations. Sports Med. Auckl. NZ 44 Suppl 1, S79-85 (2014).
Costa, R. J. S., Snipe, R. M. J., Kitic, C. M. & Gibson, P. R. Systematic review: exercise-induced gastrointestinal syndrome-implications for health and intestinal disease. Aliment. Pharmacol. Ther. 46, 246–265 (2017).
Davison, G., Jones, A. W., Marchbank, T. & Playford, R. J. Oral bovine colostrum supplementation does not increase circulating insulin-like growth factor-1 concentration in healthy adults: results from short- and long-term administration studies. Eur. J. Nutr. 59, 1473–1479 (2020).
Chantler, S. et al. The Effects of Exercise on Indirect Markers of Gut Damage and Permeability: A Systematic Review and Meta-analysis. Sports Med. Auckl. NZ 51, 113–124 (2021).
Aune, S. K. et al. Gut Leakage Markers in Response to Strenuous Exercise in Patients with Suspected Coronary Artery Disease. Cells 10, (2021).
Marchbank, T. et al. The nutriceutical bovine colostrum truncates the increase in gut permeability caused by heavy exercise in athletes. Am. J. Physiol. Gastrointest. Liver Physiol. 300, G477-484 (2011).
Davison, G., Marchbank, T., March, D. S., Thatcher, R. & Playford, R. J. Zinc carnosine works with bovine colostrum in truncating heavy exercise-induced increase in gut permeability in healthy volunteers. Am. J. Clin. Nutr. 104, 526–536 (2016).
Edwards, K. H. et al. The influence of exercise intensity and exercise mode on gastrointestinal damage. Appl. Physiol. Nutr. Metab. Physiol. Appl. Nutr. Metab. 46, 1105–1110 (2021).
Skarpańska-Stejnborn, A., Basta, P., Sadowska, J. & Pilaczyńska-Szcześniak, L. Effect of supplementation with chokeberry juice on the inflammatory status and markers of iron metabolism in rowers. J. Int. Soc. Sports Nutr. 11, 48 (2014).
Skarpańska-Stejnborn, A. et al. Effects of cranberry (Vaccinum macrocarpon) supplementation on iron status and inflammatory markers in rowers. J. Int. Soc. Sports Nutr. 14, 7 (2017).
Faul, F., Erdfelder, E., Lang, A.-G. & Buchner, A. G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav. Res. Methods 39, 175–191 (2007).
Snipe, R. M. J., Khoo, A., Kitic, C. M., Gibson, P. R. & Costa, R. J. S. Carbohydrate and protein intake during exertional heat stress ameliorates intestinal epithelial injury and small intestine permeability. Appl. Physiol. Nutr. Metab. Physiol. Appl. Nutr. Metab. 42, 1283–1292 (2017).
Mäestu, J., Jürimäe, J. & Jürimäe, T. Monitoring of performance and training in rowing. Sports Med. Auckl. NZ 35, 597–617 (2005).
Bizjak, D. A. et al. Differences in Immune Response During Competition and Preparation Phase in Elite Rowers. Front. Physiol. 12, 803863 (2021).
Voth, M. et al. I-FABP is a Novel Marker for the Detection of Intestinal Injury in Severely Injured Trauma Patients. World J. Surg. 41, 3120–3127 (2017).
McKenna, Z. et al. The effect of prolonged interval and continuous exercise in the heat on circulatory markers of intestinal barrier integrity. Eur. J. Appl. Physiol. 122, 2651–2659 (2022).
van Wijck, K. et al. Exercise-induced splanchnic hypoperfusion results in gut dysfunction in healthy men. PloS One 6, e22366 (2011).
March, D. S. et al. Intestinal fatty acid-binding protein and gut permeability responses to exercise. Eur. J. Appl. Physiol. 117, 931–941 (2017).
Barberio, M. D. et al. Systemic LPS and inflammatory response during consecutive days of exercise in heat. Int. J. Sports Med. 36, 262–270 (2015).
Snipe, R. M. J., Khoo, A., Kitic, C. M., Gibson, P. R. & Costa, R. J. S. The impact of exertional-heat stress on gastrointestinal integrity, gastrointestinal symptoms, systemic endotoxin and cytokine profile. Eur. J. Appl. Physiol. 118, 389–400 (2018).
Ajamian, M., Steer, D., Rosella, G. & Gibson, P. R. Serum zonulin as a marker of intestinal mucosal barrier function: May not be what it seems. PloS One 14, e0210728 (2019).
van Wijck, K. et al. Exercise-induced splanchnic hypoperfusion results in gut dysfunction in healthy men. PloS One 6, e22366 (2011).
ter Steege, R. W. F. & Kolkman, J. J. Review article: the pathophysiology and management of gastrointestinal symptoms during physical exercise, and the role of splanchnic blood flow. Aliment. Pharmacol. Ther. 35, 516–528 (2012).
Rehrer, N. J., Smets, A., Reynaert, H., Goes, E. & De Meirleir, K. Effect of exercise on portal vein blood flow in man. Med. Sci. Sports Exerc. 33, 1533–1537 (2001).
Usui, M., Hanamura, N., Hayashi, T., Kawarada, Y. & Suzuki, K. Molecular cloning, expression and tissue distribution of canine lipopolysaccharide (LPS)-binding protein. Biochim. Biophys. Acta 1397, 202–212 (1998).
Dullah, E. C. & Ongkudon, C. M. Current trends in endotoxin detection and analysis of endotoxin-protein interactions. Crit. Rev. Biotechnol. 37, 251–261 (2017).
Wallett, A. et al. Repeated-Sprint Exercise in the Heat Increases Indirect Markers of Gastrointestinal Damage in Well-Trained Team-Sport Athletes. Int. J. Sport Nutr. Exerc. Metab. 32, 153–162 (2022).
Ghosh, S. et al. Elevated muscle TLR4 expression and metabolic endotoxemia in human aging. J. Gerontol. A. Biol. Sci. Med. Sci. 70, 232–246 (2015).
Etxebarria, N. et al. Dietary Intake and Gastrointestinal Integrity in Runners Undertaking High-Intensity Exercise in the Heat. Int. J. Sport Nutr. Exerc. Metab. 31, 314–320 (2021).
GASKELL, S. K., RAUCH, C. E., PARR, A. & COSTA, R. J. S. Diurnal versus Nocturnal Exercise—Effect on the Gastrointestinal Tract. Med. Sci. Sports Exerc. 53, (2021).
Etxebarria, N. et al. Dietary Intake and Gastrointestinal Integrity in Runners Undertaking High-Intensity Exercise in the Heat. Int. J. Sport Nutr. Exerc. Metab. 31, 314–320 (2021).

No competing interests reported.

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Effect of 2000-meter rowing test on parameters of intestinal integrity in elite rowers during competitive phase - observational study.

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Abstract

Figures

Introduction

Results

Participants

Dietary intake

2000-meters rowing test

Markers of gut permeability and inflammation

Discussion

Conclusion

Study limitations

Material and methods

Participants

Rowing test

Training program during sports camp

Food intake

Blood sampling and analyses

Statistical analyses

Abbreviations

Declarations

References

Additional Declarations

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