Physiological and metabolic responses of Parabadminton athletes to field simulated effort.

BACKGROUND: Due to the increase in the number of Parabadminton (PBd) athletes and the lack of scientific knowledge of the sport, it is important to evaluate performance variables in different game stimuli. Thus, this study sought to examine the physiological and metabolic responses in a simulated effort protocol in PBd athletes. METHODS: Forty-seven volunteers (WH1=7; WH2=9; SL3=8; SL4=9; SU5=6; SH6=8) performed a simulated effort protocol, consisting of 2 blocks of activities (1st change of direction + 1st simulated effort; 2nd change of direction + 2nd simulated effort). Peak and average oxygen consumption (VO2peak and VO2avg), peak, percentage, and average heart rate (HRmax, %HRmax, and HRavg), percentage of carbohydrates and lipids contributions (%CARB and %FAT), and average and total energy expenditure (EEavg and EEtotal) were evaluated. The data was compared between protocol stages, functional classes (FCs), and court size. It was adopted P<0.05. RESULTS: Differences were found between the stages of the protocol in VO2peak (P=0.0008), VO2avg (P=0.0004); HRmax (P<0.0001); %HRmax (P=0.0001), HRavg (P=0.0001), %CARB (P=0.0001), %FAT (P=0.0001), EEavg (P=0.0002), and EEtotal (P=0.008). Among FCs, SL4 athletes were superior to WH1 athletes for VO2peak (P=0.075), VO2avg (P=0.022), EEavg (P=0.011), and EEtotal (P=0.022). Athletes who completed protocol in the full court were greater than half court for VO2peak (P<0.001), VO2avg (P<0.001), %HRmax (P=0.032), HRavg (P=0.018), %CARB (P=0.022), %FAT (P=0.022), and EEavg (P=0.016). CONCLUSIONS: PBd athletes belonging to higher FCs (4, 5, and 6) and who cover greater distances on the court exhibit physiological and metabolic responses under greater influence of the type of disability.

The gold rush in para swimming: changes in the speed curve of a visually impaired world and paralympic champion - a case study.

This case study examined the association between 50 m freestyle and speed curve parameters of a world-class Paralympic swimmer and analysed the changes in speed curves and their frequency components across her performance levels. From 2018 to 2021, a visually impaired female swimmer (26.59 s in 50 m freestyle, S12 class) underwent 22 tests to obtain instantaneous speed synchronised with video recording. She regularly performed 50 m freestyle in competitions and time trials. The fast Fourier transformation method converted the speed signal into frequency domains and determined the relative contribution of the harmonics with two maxima and minima (H2, arms actions) and six maxima and minima (H6, legs actions). The functional paired t-test compared the speed curves at the beginning (PRE) and end (POST) of the analysed period. The 50 m freestyle time correlated with average speed (r = -0.50, p = 0.02). The contribution of H6 increased in the first year and remained large, whereas the contribution of H2 was lower throughout the whole period. POST was faster than PRE in five moments that coincide with the downward leg kick moments. These changes allowed her to stay longer at the upper part of the curve and improve performance over time.

DNA-templated self-assembly of bradykinin into bioactive nanofibrils.

Bradykinin (BK) is a peptide hormone that plays a crucial role in blood pressure control, regulates inflammation in the human body, and has recently been implicated in the pathophysiology of COVID-19. In this study, we report a strategy for fabricating highly ordered 1D nanostructures of BK using DNA fragments as a template for self-assembly. We have combined synchrotron small-angle X-ray scattering and high-resolution microscopy to provide insights into the nanoscale structure of BK-DNA complexes, unveiling the formation of ordered nanofibrils. Fluorescence assays hint that BK is more efficient at displacing minor-groove binders in comparison with base-intercalant dyes, thus, suggesting that interaction with DNA strands is mediated by electrostatic attraction between cationic groups at BK and the high negative electron density of minor-grooves. Our data also revealed an intriguing finding that BK-DNA complexes can induce a limited uptake of nucleotides by HEK-293t cells, which is a feature that has not been previously reported for BK. Moreover, we observed that the complexes retained the native bioactivity of BK, including the ability to modulate Ca2+ response into endothelial HUVEC cells. Overall, the findings presented here demonstrate a promising strategy for the fabrication of fibrillar structures of BK using DNA as a template, which keep bioactivity features of the native peptide and may have implications in the development of nanotherapeutics for hypertension and related disorders.

Current Technologies and Practices to Assess External Training Load in Paralympic Sport: A Systematic Review.

CONTEXT: Knowing the methods to assess the external load in Paralympic sports can help multidisciplinary teams rely on scientific evidence to better prescribe and monitor the athlete's development, improving sports performance and reducing the risk of injury/illness of Paralympic athletes. OBJECTIVES: This review aimed to systematically explore the current practices of quantifying the external load in Paralympic sports and provide an overview of the methods and techniques used. EVIDENCE ACQUISITION: A search in PubMed, Web of Science, Scopus, and EBSCO was carried out until November 2022. The measures of interest were objective methods for quantifying the external load of training or competition. The inclusion criteria for the studies were as follows: (1) peer-reviewed article; (2) the population were Paralympic athletes; (3) evaluated during training or competition; (4) reported at least one external load measure; and (5) published in English, Portuguese, or Spanish. EVIDENCE SYNTHESIS: Of the 1961 articles found, 22 were included because they met the criteria, and 8 methods were identified to quantify the external load in training or competition in 8 Paralympic sports. The methods varied according to the characteristics of the Paralympic sports. To date, the devices used included an internal radiofrequency-based tracking system (wheelchair rugby) a miniaturized data logger (wheelchair tennis, basketball, and rugby); a linear position transducer (powerlifting and wheelchair basketball); a camera (swimming, goalball, and wheelchair rugby); a global positioning system (wheelchair tennis); heart rate monitors that assess external load variables in set (paracycling and swimming) and an electronic timer (swimming). CONCLUSIONS: Different objective methods were identified to assess the external load in Paralympic sports. However, few studies showed the validity and reliability of these methods. Further studies are needed to compare different methods of external load quantification in other Paralympic sports.

Amyloid-like Self-Assembly of a Hydrophobic Cell-Penetrating Peptide and Its Use as a Carrier for Nucleic Acids.

Cell-penetrating peptides (CPPs) are a topical subject potentially exploitable for creating nanotherapeutics for the delivery of bioactive loads. These compounds are often classified into three major categories according to their physicochemical characteristics: cationic, amphiphilic, and hydrophobic. Among them, the group of hydrophobic CPPs has received increasing attention in recent years due to toxicity concerns posed by highly cationic CPPs. The hexapeptide PFVYLI (P, proline; F, phenylalanine; V, valine; Y, tyrosine; L, leucine; and I, isoleucine), a fragment derived from the C-terminal portion of α1-antitrypsin, is a prototypal example of hydrophobic CPP. This sequence shows reduced cytotoxicity and a capacity of nuclear localization, and its small size readily hints at its suitability as a building block to construct nanostructured materials. In this study, we examine the self-assembling properties of PFVYLI and investigate its ability to form noncovalent complexes with nucleic acids. By using a combination of biophysical tools including synchrotron small-angle X-ray scattering and atomic force microscopy-based infrared spectroscopy, we discovered that this CPP self-assembles into discrete nanofibrils with remarkable amyloidogenic features. Over the course of days, these fibrils coalesce into rodlike crystals that easily reach the micrometer range. Despite lacking cationic residues in the composition, PFVYLI forms noncovalent complexes with nucleic acids that retain ß-sheet pairing found in amyloid aggregates. In vitro vectorization experiments performed with double-stranded DNA fragments indicate that complexes promote the internalization of nucleic acids, revealing that tropism toward cell membranes is preserved upon complexation. On the other hand, transfection assays with splice-correction oligonucleotides (SCOs) for luciferase expression show limited bioactivity across a narrow concentration window, suggesting that the propensity to form amyloidogenic aggregates may trigger endosomal entrapment. We anticipate that the findings presented here open perspectives for using this archetypical hydrophobic CPP in the fabrication of nanostructured scaffolds, which potentially integrate properties of amyloids and translocation capabilities of CPPs.

Self-assembly and intracellular delivery of DNA by a truncated fragment derived from the Trojan peptide Penetratin.

Penetratin is a short Trojan peptide that attracts great interest in biomedical research for its capacity to translocate biological membranes. Herein, we study in detail both self-assembly and intracellular delivery of DNA by the heptamer KIWFQNR, a truncated peptide derived from Penetratin. This shortened sequence possesses a unique design with bolaamphiphilic characteristics that preserves the longest noncationic amino acid portion found in Penetratin. These features convey amphipathicity to assist self-assembly and make it a suitable model for exploring the role of hydrophobic residues for peptide interaction and cell uptake. We show that the fragment forms peptiplexes (i.e., peptide-DNA complexes), and aggregates into long nanofibers with clear ß-sheet signature. The supramolecular structure of nanofibers is likely composed of DNA cores surrounded by a peptide shell to which the double helix behaves as a template and induces fibrillization. A nucleation and growth mechanism proceeding through liquid-liquid phase separation of coacervates is proposed for describing the self-assembly of peptiplexes. We also demonstrate that peptiplexes deliver double-stranded 200 bp DNA into HeLa cells, indicating its potential for preparing non-viral vectors for oligonucleotides through noncovalent strategies. Since the main structural features of native Penetratin are conserved in this simpler fragment, our findings also highlight the role of uncharged amino acids for structuration, and thus for the ability of Penetratin to cross cell membranes.

Effects of compression clothing on speed-power performance of elite Paralympic sprinters: a pilot study.

BACKGROUND: Compression garments are thought to aid performance in some selected speed-power activities owing to improved sensory feedback and proprioception. The aim of this study was to test the effects of using compression garments on speed and power-related performances in elite sprinters with visual impairment, who rely more on proprioception to perform than their Olympic peers. Eight top-level Paralympic sprinters competing in 100- and 200-m races performed, in the following order: unloaded squat jump (SJ), loaded jump squat (JS) and sprint tests over 20- and 70-m distances; using or not the compression garment. The maximum mean propulsive power value obtained during the JS attempts (starting at 40 % of their body mass, after which a load of 10 % of body mass was progressively added) was considered for data analysis purposes. The athletes executed the SJ and JS attempts without any help from their guides. Magnitude-based inference was used to analyze the results. FINDINGS: The unloaded SJ was possibly higher in the compression than the placebo condition (41.19 ± 5.09 vs. 39.49 ± 5.75 cm). Performance differences in the loaded JS and sprint tests were all rated as unclear. CONCLUSIONS: It was concluded that the acute enhancement in vertical jump ability should be explored in the preparation of Paralympic sprinters during power-related training sessions. However, chronic effects in Paralympic athletes wearing compression garments need to be further tested, in order to support its use as a specific training aid.

Análise da potência aeróbia de futebolistas por meio de teste de campo e teste laboratorial / Analysis of aerobic power of soccer players through field test and laboratory test / Análisis de la capacidad aeróbica de futbolistas por medio de test de campo y test en laboratório

Introdução: Há métodos diretos e indiretos que são utilizados pelos clubes de futebol para avaliar, acompanhar e determinar o VO2max dos jogadores, sendo este muito importante para o rendimento e a recuperação dos atletas durante uma partida. Objetivo: Avaliar o nível de correlação entre as medidas de VO2max por meio da análise direta de gases e do teste de campo Yo-Yo Intermitente Recovery Level 1 (Yo-YoIR1). Métodos: Participaram do estudo 24 jogadores de futebol da categoria SUB-20 de um clube do estado de São Paulo, Brasil, com estatura 1,72±0,08 m e massa corporal 61,17±9,18 kg, com no mínimo cinco anos de prática na modalidade. Os atletas realizaram o teste de análise direta dos gases em esteira ergométrica e após 48 horas foi realizado o Yo-Yo IR1. Resultados: Os resultados apontaram uma correlação significante entre os testes (r=0,524; p<0,01), porém o Yo-Yo IR1 subestimou as medidas de análise direta dos gases em laboratório (44,98ml/kg/min e 48,14ml/kg/min, respectivamente). Conclusão: Os resultados apontaram uma correlação moderada entre as medidas de VO2max, dessa forma pode-se utilizar ambos os testes para análise da potência aeróbia dos jogadores de futebol, desde que seja repetido o mesmo protocolo nas avaliações subsequentes. .

Introduction: There are direct and indirect methods that are used by soccer clubs to assess, monitor and determine the VO2max of soccer players, which is very important for the performance and recovery of athletes during a match. Objective: The aim of this study was to assess the level of the correlation between measures of VO2max by direct gas analysis and by the field test Yo-Yo Intermittent Recovery Level 1 (Yo-Yo IR1). Methods: The study included 24 Brazilian male soccer players from under 20 category, of a club in the State of São Paulo, Brazil with stature of 1.72 ± 0.08 meter and body mass of 61.17 ± 9.18 kg, with at least five years of practice in the sport. The athletes performed the direct analysis of gases test on a treadmill 48 hours later the Yo-Yo IR1 was performed. Results: The results revealed a significant correlation between tests (r=0.524; p<0.01), but Yo-Yo IR1 underestimated measures of direct analysis of gases in the laboratory (44.98ml/kg/min and 48.14ml/kg/min, respectively). Conclusion: The results showed a moderate correlation between measures of VO2max, that way both tests can be used to analyze the aerobic power of soccer players, since the same protocol is repeated in subsequent evaluations. .

Introducción: Los métodos directos e indirectos son utilizados por los clubes de fútbol para evaluar, monitorear y determinar el VO2max de los jugadores, lo que es muy importante para el rendimiento y la recuperación de los atletas durante un partido. Objetivo: Evaluar el nivel de correlación entre las medidas de VO2max de análisis directo de gases y la prueba de campo Yo-Yo Intermitente Recovery Nivel 1 (Yo-YoIR1). Métodos: El estudio incluyó a 24 futbolistas categoría SUB-20 de un club en el Estado de São Paulo, Brasil, con estatura de 1,72 ± 0,08 metro y masa corporal de 61,17 ± 9,18 Kg, con al menos cinco años de práctica en la modalidad. Los atletas realizaron el análisis directo de los gases en una caminadora y después de 48 horas se realizó el Yo-Yo IR1. Resultados: Los resultados revelaron una correlación significativa entre los ensayos (r = 0,524, p < 0,01), pero el Yo-Yo IR1 ha subestimado las mediciones de laboratorio del análisis directo de gases (44,98 ml/Kg/min. y 48,14 ml/Kg/min., respectivamente). Conclusión: Los resultados indicaron una correlación moderada entre las medidas de VO2max, de esta manera se pueden utilizar ambas las pruebas para analizar la capacidad aeróbica de los jugadores de fútbol, siempre que se repita el mismo protocolo en las evaluaciones posteriores. .

Reproducibility of an incremental treadmill VO(2)max test with gas exchange analysis for runners.

The evaluation of performance through the application of adequate physical tests during a sportive season may be a useful tool to evaluate training adaptations and determine training intensities. For runners, treadmill incremental VO(2)max tests with gas exchange analysis have been widely used to determine maximal and submaximal parameters such as the ventilatory threshold (VT) and respiratory compensation point (RCP) running speed. However, these tests often differ in methodological characteristics (e.g., stage duration, grade, and speed increment size), and few studies have examined the reproducibility of their protocol. Therefore, the aim of this study was to verify the reproducibility and determine the running speeds related to maximal and submaximal parameters of a specific incremental maximum effort treadmill protocol for amateur runners. Eleven amateur male runners underwent 4 repetitions of the protocol (25-second stages, each increasing by 0.3 km·h in running speed while the treadmill grade remained fixed at 1%) after 3 minutes of warm-up at 8-8.5 km·h. We found no significant differences in any of the analyzed parameters, including VT, RCP, and VO(2)max during the 4 repetitions (p > 0.05). Further, the results related to running speed showed high within-subject reproducibility (coefficient of variation < 5.2%). The typical error (TE) values for running speed related to VT (TE = 0.62 km·h), RCP (TE = 0.35 km·h), and VO(2)max (TE = 0.43 km·h) indicated high sensitivity and reproducibility of this protocol. We conclude that this VO(2)max protocol facilitates a clear determination of the running speeds related to VT, RCP, and VO(2)max and has the potential to enable the evaluation of small training effects on maximal and submaximal parameters.

Interpretação metabólica dos parâmetros ventilatórios obtidos durante um teste de esforço máximo e sua aplicabilidade no esporte / Metabolic interpretation of ventilatory parameters during maximal effort test and their applicability to sports

A determinação das velocidades atingidas no limiar ventilatório (LV), ponto de compensação respiratório(PCR) e consumo máximo de O2 (VO2max) através de um teste de esforço máximo, é uma ferramenta importante para aaplicação de intensidades de treinamento específicas e individualizadas. Mas para poder interpretar os dados de uma forma abrangente, também é importante o entendimento das respostas metabólicas presentes no ajuste dos sistemas de transporte e utilização de O2 e produção de CO2 durante a realização do teste. Esta revisão apresenta um panorama das respostas metabólicas que acontecem durante a realização de um teste de esforço máximo hipotético, e a aplicabilidade dos valores obtidos no treinamento de atletas.

One important tool for producing specific and individualized training intensities is to determine ventilatory threshold (VT), respiratory compensation point (RCP) and maximal oxygen uptake (VO2max) by means of maximum effort testing. However, in order to be able to interpret these data in a wide-ranging manner, it is also important to understand the metabolic responses that occur during the test as the systems transporting and utilizing O2 and producing CO2 adjust. This review article presents an overview of the metabolic responses that take place during a hypothetical maximum effort test, and the applicability of the figures thus obtained to the training of athletes.