Percorrer por autor "Leite , Luciano Bernardes"
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- Acute Effects of Nitrate-Rich Beetroot Juice on Cardiovascular and Hemodynamic Responses to Flywheel Resistance Exercise: A Randomized, Double-Blind, Placebo-Controlled Crossover TrialPublication . Primo, Mateus Chaves; Viana, Ítalo Santiago Alves; Goulart-Silva, Leonardo Silveira; Machado, Wanderson Matheus Lopes; Leite , Luciano Bernardes; Forte, Pedro; Calhelha, Ricardo C.; Monteiro, António M.; Branquinho, Luís; Silva, Sandro Fernandes; Oliveira, Claudia Eliza Patrocínio de; Moreira, Osvaldo CostaBeetroot juice is a popular nutritional resource in sports due to its ergogenic effects, promoting vasodilation, hypotension, improved energy efficiency, and reduced oxygen cost. However, its role in modulating the autonomic nervous system during strength training remains understudied. This study assessed the effects of acute nitrate-rich beetroot juice supplementation on cardiovascular and hemodynamic responses to flywheel resistance exercise. Fifteen male participants (age 22 +/- 3.64 years) from the Federal University of Vi & ccedil;osa completed a crossover, double-blind, placebo-controlled trial. Each participant consumed either 400 mg of standardized nitrate or a placebo before performing 4 sets of 8-12 repetitions at 100% of their maximum concentric strength using a leg extension exercise, with 90 s recovery intervals. Heart rate, blood pressure, oxygen saturation, and subjective perception of effort were measured after each set. Data were analyzed using SPSS 23, employing the Shapiro-Wilk normality test, t-test for related samples, and MANOVA with time and supplement factors. NO3- supplementation led to a smaller increase in systolic blood pressure (SBP) during exercise compared to the placebo and reduced diastolic blood pressure (DBP) in the last set, reflecting decreased peripheral vascular resistance. However, no significant effects were observed for heart rate, rate-pressure product, oxygen saturation, time under tension, or subjective perception of effort. These findings suggest that NO3- supplementation can offer cardiovascular benefits by attenuating blood pressure increases during strength training, highlighting its potential as a low-risk ergogenic aid for healthy young men.
- 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.
- 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 differences in performance and pacing in the greatest Quintuple Iron ultra-triathlon race in history: The IUTA World Championship 2024 in FrancePublication . Knechtle, Beat; Leite , Luciano Bernardes; Duric, Sasa; Cuk, Ivan; Andrade, Marilia Santos; Scheer, Volker; Nikolaidis, Pantelis Theo; Weiss, Katja; Rosemann, Thomas; Forte, PedroPacing in ultra-triathlon has been investigated by analyzing lap times from Double to Deca Iron ultra-triathlon for World Cup races but not for a World Championship. The present study aimed to investigate pacing in ultra-triathletes competing in the fastest and largest World Championship in Quintuple Iron ultra-triathlon ever held in history. A total of 11 female and 24 male finishers who completed the 2024 Quintuple Ultra Triathlon World Championship in Colmar, France, were analyzed. Independent t-tests assessed sex-based performance variations with effect sizes (Cohen's d). A two-way ANOVA evaluated the effects of sex and performance quartiles on cycling and running, with eta squared (eta(2)) used to measure effect sizes. Overall, men were slower in swimming and cycling and faster in running and overall race time. The variability in lap times was similar in cycling for both women and men but higher in running for women. There was a significant interaction between sex and performance quartiles in cycling but not running. For cycling, the variability in performance was higher in men compared to women; for running, it was similar for both women and men. The finding that women outperformed men in swimming and cycling, likely due to the elite nature of the World Championship, which featured a highly selected and committed female cohort with a high completion rate. While both sexes showed consistent pacing in cycling, women exhibited greater variability in running, possibly due to more frequent breaks.
- 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.