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- Case Report: Case study of 100 consecutive IRONMAN®-distance triathlons—impact of race splits and sleep on the performance of an elite athletePublication . Knechtle, Beat; Leite , Luciano Bernardes; Forte, Pedro; Andrade, Marilia Santos; Cuk, Ivan; Nikolaidis, Pantelis Theo; Scheer, Volker; Weiss, Katja; Rosemann, ThomasLong-distance triathletes such as IRONMAN (R) and ultra-triathletes competing in longer race distances continue to extend ultra-endurance limits. While the performance of 60 IRONMAN (R)-distance triathlons in 60 days was the longest described to date, we analysed in the present case study the impact of split disciplines and recovery in one athlete completing 100 IRONMAN (R)-distance triathlons in 100 days. To date, this is the longest self-paced world record attempt for most daily IRONMAN (R)-distance triathlons.To assess the influence of each activity's duration on the total time, the cross-correlation function was calculated for swimming, cycling, running, and sleeping times. The autocorrelation function, which measures the correlation of a time series with itself at different lags, was also employed using NumPy.The moving average for swimming slightly increased in the middle of the period, stabilizing at similar to 1.43 h. Cycling displayed notable fluctuations between similar to 5.5 and 7h, with a downward trend toward the end. The moving average for running remains high, between 5.8 and 7.2 h, showing consistency over the 100 days. The moving average for total time hovered at similar to 15 h, with peaks at the beginning, and slightly declined in the final days. The cross-correlation between swimming time and total time showed relatively low values. Cycling demonstrated a stronger correlation with total time. Running also exhibited a high correlation with total time. The cross-correlation between sleep time and swimming time presented low values. In cycling, the correlation was stronger. For running, a moderate correlation was observed. The correlation with total time was also high. The autocorrelation for swimming showed high values at short lags with a gradual decrease over time. For cycling, the autocorrelation also began strong, decreasing moderately as lags increased. Running displayed high autocorrelation at short lags, indicating a daily dependency in performance, with a gradual decay over time. The total time autocorrelation was high and remained relatively elevated with increasing lags, showing consistent dependency on cumulative efforts across all activities. In a triathlete completing 100 IRONMAN (R)-distance triathlons in 100 days, cycling and running split times have a higher influence on overall times than swimming. Swimming performance is not influenced by sleep quality, whereas cycling performance is. Swimming times slowed faster over days than cycling and running times. Any athlete intending to break this record should focus on cycling and running training in the pre-event preparation.
- Sex-specific differences in performance and pacing in the world’s longest triathlon in historyPublication . Knechtle, Beat; Leite , Luciano Bernardes; Forte, Pedro; Andrade, Marilia Santos; Nikolaidis, Pantelis Theo; Scheer, Volker; Duric, Sasa; Cuk, Ivan; Rosemann, ThomasSex differences in performance and pacing in triathlon have been studied for IRONMAN triathlons (3.8 km swimming, 180 km cycling and 42.195 km of running) and ultra-triathlons (i.e. Double-, Triple-, Quintuple- and Deca Iron ultra-triathlons) corresponding to 2x, 3x, 5x and 10x the IRONMAN triathlon distance. However, no study has to date investigated the sex difference in performance and pacing in the longest triathlon held in history, the Triple Deca Iron ultra-triathlon covering 114 km of swimming, 5,400 km of cycling and 1,266 km of running. A total of 14 triathletes (10 men and four women) competed in the 2024 Triple Deca Ultra Triathlon in Desenzano del Garda, with four men and three women officially finishing the race within the time limit. The data were analyzed to investigate performance differences across disciplines (i.e. swimming, cycling, and running), pacing strategies and sex differences. Variability was assessed using each discipline's coefficient of variation (CV). The relation-ships between CV and overall rankings were examined using linear regression analysis. Men were faster in swimming (12.4%), cycling (24.8%) and running (8.5%). Cycling showed the greatest pacing variability, while running exhibited steadier pacing, with more consistent athletes performing better overall, reflecting the unique endurance challenges of this segment. Overall, men were faster than women in all split disciplines, with the highest sex difference in cycling and the smallest in running. The analysis revealed significant differences in both cycling and running times among athletes. The variability in cycling times indicates diverse pacing strategies and endurance levels, while the running times further highlight the individual performance dynamics of the athletes. The results illustrate how variability in pacing affects cumulative performance and final rankings.
- Can physical exercise modify intestinal integrity and gut microbiota composition? A systematic review of in vivo studiesPublication . Pereira, Stephanie Michelin Santana; São José, Vinicius Parzanini Brilhante de; Silva, Alessandra da; Martins, Karina Vitoria Cipriana; Leite , Luciano Bernardes; Forte, Pedro; Natali, Antônio José; Martino, Hércia Stampini Duarte; Lucia, Ceres Mattos Della; Bressan, JosefinaThere is little evidence about how physical exercise affects the gut microbiota since studies in the field are relatively recent. Thus, we aimed to systematically review the main effects of regular physical exercise on the intestinal integrity and microbiota composition in animal models, discuss the mechanisms involved, and indicate future directions. Searches for original articles were performed in PubMed/MEDLINE, Scopus, Web of Science, and Embase. A total of 18 studies were selected. These studies suggest that physical exercise has a significant impact on the gut microbiota. Voluntary running increased the thickness of duodenal villi and microbiota diversity but reduced its richness. Low-intensity treadmill running increased the abundance of the phylum Actinobacteria and the family Bifidobacteriaceae, while that of moderate-intensity reduced the Bacteroides/Prevotella ratio. High-intensity swimming and treadmill running altered the gut microbiota, evidenced by beta-diversity, and increased the Shannon and Chao indices but reduced short-chain fatty acids. Resistance exercise increased the Chao index and altered the functionality of the gut microbiota, increasing carbohydrate metabolism and reducing lipid and amino acid metabolism. Thus, regular physical exercise of different intensities and types can modify the gut microbiota, and the exercise benefits appear to be positively associated with training intensity.
- Financial investments and sports performance in major league soccer: A comparative analysis between market value, base salary and results in conferencesPublication . Leite , Luciano Bernardes; Generoso, Sara Caco dos Lúcio; Coelho, Bruno de Cássio; Faria, Matheus Soares; Rodrigues, Pedro M.; Forte, Pedro; Schneider, André; Veneroso, Christiano EduardoThis study examines the link between financial investments and sports performance in Major League Soccer (MLS) during 2023. It finds that higher investments do not ensure superior outcomes. In the Eastern Conference, Cincinnati excelled with modest financial figures ($11.46M base salary, $13.20M Guaranteed Compensation, and €29.25M market value), while higher-spending teams like Inter Miami and Toronto lagged behind. Similarly, in the Western Conference, St. Louis City led with 56 points, despite a lower budget ($9.49M base salary, $10.51M Guaranteed Compensation, €23.03M market value), outperforming higher spenders like Seattle Sounders and LAFC. Correlation analysis revealed negative associations between points and base salary (-0.52) and Guaranteed Compensation (-0.61) in the Eastern Conference, while points in the Western Conference showed weak correlations with financial variables. The study underscores the critical role of financial efficiency over mere expenditure for success in MLS.
- Causas e consequências de quedasPublication . Monteiro, António M.; Encarnação, Samuel; Teixeira, José Eduardo; Branquinho, Luís; Leite , Luciano Bernardes; Rodrigues, Filipe; Afonso, Pedro; Valente, Nuno; Forte, PedroAs quedas entre os idosos representam uma preocupação significativa de saúde pública, caracterizada por uma complexa interação de fatores intrínsecos e extrínsecos que contribuem para a sua prevalência e gravidade. Com o envelhecimento da população global, projeta-se que a incidência de quedas aumente, levando a maior morbidade, mortalidade e custos de saúde associados a lesões relacionadas com quedas. A natureza multifacetada das quedas exige uma compreensão abrangente das suas causas e consequências, que podem ser categorizadas em vários domínios, incluindo fatores fisiológicos, psicológicos e ambientais.
- 24-Hour Ultra-Marathon Running: A Narrative Review of Performance Factors and Physiological ImpactsPublication . Knechtle, Beat; Braschler, Lorin; Weiss, Katja; Scheer, Volker; Duric, Sasa; Leite , Luciano Bernardes; Forte, Pedro; Nikolaidis, Pantelis T.; Chlíbková, Daniela; Rosemann, ThomasThe 24-hour ultra-marathon is a specific race format with a long tradition and high popularity. To date, no comprehensive review has systematically summarized the scientific literature on 24-hour ultra-marathon running. We performed a comprehensive search in the PubMed and Scopus databases, covering studies published until the end of 2025. The participation of runners and finishers in 24-hours has increased in the past decades. Most participants in 24-hours are age group or master runners older than 35 years. 24-hour ultra-runners typically cover distances exceeding 100 km per event, with an average distance ranging from similar to 150-160 km, while the top performers can achieve over 200 km. Men achieve greater distances than women. The best performance is achieved at 40-50 years. The most important predictive variables in 24-hours are training, nutrition, previous experience, and pacing; anthropometric characteristics seemed of no predictive value. During 24-hours, athletes ingest mainly carbohydrates and experience an energy deficit, but rarely exercise-associated hyponatremia. A 24-hour run leads to decrease in body mass, which can be due to dehydration, a loss of skeletal muscle mass, and/or a loss of fat mass. A 24-hour run has effects on the cardiovascular system (i.e., decrease in blood pressure, changes in cardiac biomarkers, and changes in electrocardiogram and echocardiographic findings), the kidneys (i.e. reversible impairment of kidney function), the digestive system (i.e., gastrointestinal discomfort, reversible increase in liver enzymes), the immune system (i.e., increase in immune markers) and the hematological system (i.e., decrease in red blood cells, increase in white blood cells). All negative effects are resolved within 2-3 days. In summary, 24-hour ultra-marathon runners are master athletes with extensive experience, optimal training preparation, and optimal nutrition to complete a 24-hour run successfully. The adverse effects on the heart, kidneys, immune system, and digestive tract generally resolve within a few days after the event. Future studies need to investigate nutrition after the race to enhance recovery and the impact of training and competing in this specific race format on the locomotor system (i.e. skeleton, muscles, tendons, joints).
- Envelhecimento fisiológicoPublication . Forte, Pedro; Encarnação, Samuel; Teixeira, José Eduardo; Branquinho, Luís; Leite , Luciano Bernardes; Rodrigues, Filipe; Afonso, Pedro Miguel Vaz; Valente, Nelson; Monteiro, António M.O envelhecimento fisiológico é um processo multifacetado que envolve alterações ao nível celular, tecidular e sistémico. À medida que os indivíduos envelhecem, observa-se um declínio gradual de diversas funções fisiológicas, o que compromete a capacidade do corpo de manter a homeostasia e responder adequadamente a fatores de stress. Este processo de envelhecimento é influenciado por fatores genéticos, ambientais e de estilo de vida, que em conjunto determinam a taxa e a extensão do envelhecimento.