Correlation between skin temperature in the lower limbs and biochemical marker, performance data, and clinical recovery scales.

The aim of this study was to evaluate the correlation between tools commonly used in the detection of physiological changes, such as clinical complaints, a biochemical marker of muscle injury, and performance data during official matches, with infrared thermography, which has been commonly used in the possible tracking of musculoskeletal injuries in athletes. Twenty-two athletes from a professional soccer club (age 27.7 ± 3.93 years; BMI 24.35 ± 1.80 kg/cm2) were followed during the season of a national championship, totaling 19 matches with an interval of 7 days between matches. At each match, the athletes used a Global Positioning System (GPS) device to collect performance data. Forty-eight hours after each match, every athlete's perception of recovery, fatigue, and pain was documented. Blood was collected for creatine kinase (CK) analysis, and infrared thermography was applied. Only athletes who presented pain above 4 in either limb were included for thermographic analysis. Each thermographic image was divided into 14 regions of interest. For statistical analysis, we included only the images that showed differences ≥ 1° C. Data normality was verified by the Kolmogorov-Smirnov test with Dallal-Wilkinson-Lilliefors correction. We used the Pearson correlation coefficient to verify the correlation between infrared thermography and the biochemical marker, performance data, and clinical recovery scales. No correlation was observed between mean skin temperature and blood CK levels, pain level, perception of recovery, and fatigue perception (r <0.2, p>0.05). Thus, infrared thermography did not correlate with CK level, pain, fatigue perception, or recovery, nor with performance variables within the field.

Effects of Match-Related Contextual Factors on Weekly Load Responses in Professional Brazilian Soccer Players.

This study aimed to quantify the weekly training load distributions according to match location, opponent standard, and match outcome in professional soccer players. Rate-of-perceived-exertion-based training load (sRPE) and distance- and accelerometry-based measures were monitored daily during 52 training sessions and 11 matches performed by 23 players. Athletes who played ≥ 60 min during non-congested weeks were considered for data analysis. The training days close to away matches (e.g., one day before the match = MD-1) presented greater sRPE, distance-based volume measures, and mechanical work (player load) compared to the training days close to home matches (p = 0.001-0.002; effect size (ES) = medium-large). The most distant days of the home matches (e.g., five days before the match = MD-5) presented higher internal and external loads than before away matches (p = 0.002-0.003, ES = medium). Higher sRPE, distance-based volume measures, and mechanical work were found during the middle of the week (e.g., three days before the match, MD-3) before playing against bottom vs. medium-ranking teams (p = 0.001-0.01, ES = small-medium). These metrics were lower in MD-5 before matches against bottom vs. medium-ranking opponents (p = 0.001, ES = medium). Higher values of all external load measures were observed during the training session before winning matches (MD-1) compared to a draw or loss (p < 0.001-0.001, ES = medium-large). In conclusion, the training load distribution throughout the week varied considerably according to match-contextual factors.

Effects of 22 weeks of training on functional markers and match performance of young soccer players

The aim of this study was to verify the effects of 22 weeks of training on functional markers and match performance through the use of earned points in competition. Twenty male soccer players were submitted to the same group of tests in four moments of the periodization: before the preparatory stage (T0); after the preparatory stage (T1); after the competitive stage I (T2); after the competitive stage II (T3). The functional markers were measured using the vertical and horizontal jump, T-40; Shuttle Run Test and RAST. The match performance was obtained by earned points in competition. An increase were found for all the variables analyzed for functional markers when T0 was compared with T3. In relation to the match performance, the team obtained 83.33% success in competitive stages. It is possible to conclude that training plan was efficient to improve technical-tactical skills and physical fitness of the studied athletes

Long distance run induced hydration and kidney function changes in marathoners / Corrida de longa distância induz a mudanças no estado de hidratação e na função renal em maratonistas / Funcionamiento para un cambios de larga distancia inducido en el estado de hidratación y función renal en maratonistas

The aim of the study was to verify the hydration status and the kidney function in marathoners during the training season and after a marathon race. Nine male runners were investigated during 12 weeks of training. Urine was collected in four moments; in the beginning (C1) and during (C2) the training program, before (C3) and after (C4) the competition. Urine pH was measured using reagent tapes, urine density with a refractometer, protein excretion by Bradford assay and erythrocytes and leucocytes by microscopy. Changes were observed when C-4 was compared to the other collection times for all variables investigated. It is possible to conclude that physical exertion induced important changes in the hydration status and glomerular membrane selectivity to macromolecules, modifying the kidney function of the marathoners in C4.

O objetivo do estudo foi verificar o estado de hidratação e a função renal de maratonistas durante uma temporada preparatória e após a competição. Foram estudados nove maratonistas durante 12 semanas de treinamento. A urina foi coletada em quatro momentos: antes (C1) e durante (C2) o protocolo de treinamento, antes (C3) e após (C4) a competição. Foram mensurados o pH a partir de tiras de reagentes, a densidade por meio do refratômetro, a proteinúria pelo ensaio de Bradford, concentração de eritrócitos e de leucócitos por microscopia. Alterações foram encontradas quando comparado o C-4 com as coletas anteriores para todas as variáveis estudadas. Pode-se concluir que o exercício físico induziu a modificações importantes no estado de hidratação dos corredores e na função da membrana glomerular, modificando assim, a função renal dos maratonistas no momento pós prova.

El objetivo del estudio fue determinar el estado de hidratación y la función renal en los corredores de maratón durante una temporada de preparación y después de la competición. Se estudiaron nueve corredores durante 12 semanas de entrenamiento. La orina se recogió en cuatro momentos: antes y durante el protocolo de entrenamiento, antes y después de la competición. PH de tiras reactivas, de densidad a través del refractómetro, proteinuria por Bradford ensayo, concentración de eritrocitos y leucocitos fueron medidos por microscopía. No se encontraron cambios al comparar el C-4 con las colecciones anteriores para todas las variables. Se puede concluir que el ejercicio induce cambios significativos en el estado de hidratación de los corredores y la función de la membrana glomerular, modificando de este modo la función renal del tiempo de maratón después de la carrera.