Figueiredo, DH, Figueiredo, DH, Moreira, A, Gonçalves, HR, and Stanganelli, LCR. Effect of overload and tapering on individual heart rate variability, stress tolerance, and intermittent running performance in soccer players during a preseason. J Strength Cond Res 33(5): 1222–1231, 2019—This study evaluates the weekly natural log of the root-mean-square difference of successive R-R intervals (lnRMSSDmean), its coefficient of variation (lnRMSSDcv), training load (TL), stress tolerance (ST), and changes in intermittent running performance in response to a 2-week overload (OL) followed by a 1-week taper (TP) during a preseason. Additionally, we determined the relationships between these variables. Ultra-short lnRMSSD, psychometric responses, and ratings of perceived exertion were evaluated daily among 16 under-19 soccer players. At the end of each training phase, the athletes performed the Yo-Yo Intermittent Recovery test level 1 (Yo-Yo). Group analysis showed a decrease in lnRMSSDmean and ST, increases in lnRMSSDcv, and decreases in the Yo-Yo during OL, with a return to baseline levels and a trivial increase in the Yo-Yo during TP. Small to very large correlations were found between lnRMSSDmean and lnRMSSDcv values, with changes in Yo-Yo, TL, monotony, and strain during the preseason (r values ranging from −0.27 to 0.82). No correlation was found between lnRMSSD responses and ST. During OL, athletes with decreases in lnRMSSDmean and increases in lnRMSSDcv accumulated higher perceived TL, with higher monotony and overall stress, and presented a decrease in ST and intermittent running performance, interpreted as a negative adaptation in response to the maintenance of higher TL. During TP, these responses were reversed, leading to an increase in intermittent running performance. In addition, subjective measures of ST may be used to provide early indicators of training adaptation in soccer players.

The purpose of this study was to investigate the effects of chronic beetroot juice (BRJ) supplementation on 10-km running performance in recreational runners. In a double-blind, placebo-controlled, crossover-designed study, fourteen male recreational runners (age: 27.8 ± 3.4 y) performed three 10-km running tests at baseline, under the conditions of BRJ supplementation and placebo (PLA). Supplementation was administered for three days, and on the day of the assessments, the ingestion occurred two hours before each test and consisted of a dose of 420 mL of BRJ in natura (8.4 mmol NO3-/day) or PLA with depleted NO3- (0.01 mmol NO3-/day). The mean velocity (MV) was calculated and the following variables were determined: maximum heart rate (HRmax), maximal rating of perceived exertion (RPEmax), and determined at pre and post test glucose concentrations (Glycpre, Glycpost), and lactate peak. There was no main effect between conditions regarding to 10-km running time performance (BRJ: 50.1 ± 5.3; PLA: 51.0 ± 5.1 min, p = 0.391) and total MV (BRJ: 12.1 ± 1.3; PLA: 11.9 ± 1.2 km·h-1, p = 0.321), as well as in the other analyzed variables. The time to complete the first half of the test (5 km) was statistically lower in the BRJ compared to that in the PLA (P = 0.027). In conclusion, chronic supplementation with BRJ increasing MV in the first half of the test and improves the final test time of ten of the fourteen runners, although we did not find a statistically significant difference in the performance of 10-km.

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Figueiredo, DH, Figueiredo, DH, Moreira, A, Gonçalves, HR, and Dourado, AC. Dose-response relationship between internal training load and changes in performance during the preseason in youth soccer players. J Strength Cond Res 35(8): 2294–2301, 2021—The aim of this study was to describe training intensity distribution based on the session rating of perceived exertion (sRPE) and heart rate (HR) methods and examine the dose-response relation between internal training load (ITL) and change in performance of 16 youth soccer players (mean ± SD age: 18.75 ± 0.68 years, height: 175.3 ± 5.5 cm, body mass: 68.7 ± 6.5 kg, and body fat: 10.7 ± 1.2%) belonging to a Brazilian first division team during a 3-week preseason. The sRPE and HR data were registered daily to calculate the ITL and the training intensity distribution, in 3 intensity zones (low, moderate, and high). The Yo-yo Intermittent Recovery Level 1 (Yo-yo IR1) was evaluated before and after experimental period. The total time spent in the low-intensity zone (HR method) was greater (p < 0.01) compared with the moderate- and high-intensity zones. No difference was observed between training intensity zones determined by the sRPE method (p > 0.05). Negative correlations were observed between weekly mean sRPE-TL (r = −0.69), Edward's-TL (r = −0.50), and change in Yo-yo IR1. Linear regression indicated that weekly mean sRPE-TL (F 1;14 = 13.3; p < 0.01) and Edward's-TL (F 1;14 = 4.8; p < 0.05) predicted 48.7 and 25.5% of the variance in performance change, respectively. Stepwise linear regression revealed that these 2-predictor variables (F 2;13 = 18.9; p < 0.001) explained 74.5% of the variance in performance change. The results suggest that the sRPE and HR methods cannot be used interchangeably to determine training intensity distribution. Moreover, sRPE-TL seems to be more effective than the HR-based TL method to predict changes in performance in youth soccer players.

Background: Long distance practice running are growing and nutritional ergogenic are commonly used as a potential aid in final training and competition performance. Caffeine (CAF) and carbohydrates (CHO) are among the most commonly used supplements due to their expected ergogenic properties that can optimize energetic systems. The objective of this study was to examine potential changes in 10-km running performance with acute isolated and combined CAF and CHO supplementation. Material and method: Fifteen recreational endurance-trained runners performed four 10-km running performance on an official athletic track (400 m) under four supplementation conditions: placebo and placebo (PLA+PLA), placebo and caffeine (PLA+CAF), placebo and carbohydrates (PLA+CHO), caffeine and carbohydrates (CAF+CHO). CAF and CHO supplementation consisted of capsules of 6 mg·kg-1 and 8% CHO solution (1 g·kg-1) respectively, ingested 60 and 30 minutes before the performance tests. Placebo was obtained through empty capsules for CAF and juice for CHO without sugar (Clight®). During each trial running speed to calculate 10-km mean velocity (MV) and maximum heart rate (HRmax) were analyzed. Results: There was a difference in the pacing strategy adopted by the runners with higher MV during the initial phase for PLA+CAF and CAF+CHO groups and in the final phase for PLA+ CHO. However, there was no statistically significant difference in 10-km running performance between the conditions, as well as for HRmax. Conclusions: The use of acute, isolated and combined CAF+CHO supplementation had influence in the pacing strategy, but no in 10- km final performance, of recreational runners.

RESUMO: a inclusão de alunos com deficiência é prevista em lei e manter boas estruturas físicas e pedagógicas na escola é um ponto fundamental para que o acesso possa acontecer. A Educação Física faz parte desta inclusão e pode proporcionar grandes melhoras na qualidade de vida de alunos com deficiência. Este estudo teve como objetivo compreender as percepções do aluno com deficiência a respeito das aulas de Educação Física. Para isso foi realizada uma pesquisa de natureza qualitativa utilizando para coleta de dados uma entrevista semiestruturada a qual foi gravada, transcrita e posteriormente analisada. A amostra foi constituída de 20 alunos com deficiência matriculados em escolas regulares da cidade de Santos Dumont -MG. A partir das entrevistas, destacou-se a percepção do aluno com deficiência a respeito da Educação Física escolar; o entendimento deles quanto ao conceito de qualidade de vida; as melhoras proporcionadas na qualidade de vida através da Educação Física; as facilidades e as dificuldades nas aulas; e as questões concernentes à relação aluno/professor e aluno/aluno. Os resultados dessa pesquisa podem auxiliar a comunidade escolar e o professor de Educação Física a melhorarem a inclusão nas escolas regulares. Além disso, as percepções dos alunos com deficiência sobre as aulas podem ajudar o professor na busca de um ambiente melhor com aulas que atendam a todos e proporcionem uma melhor qualidade de vida. PALAVRAS-CHAVE:Educação Especial. Educação Física. Pessoas com Deficiência. Qualidade de Vida. ABSTRACT:The inclusion of disabled students is based on the law and the adaptation of physical and pedagogical structure at school represents a key point in order to make the access happen. Physical education is a part of the social inclusion and can provide great improvements in quality of life of students with disabilities. This research aimed to verify the perception of the student with disabilities on physical education classes. Therefore, a qualitative research was carried out, using a semi structured interview to 1 http://dx

The aim of the study was to compare the players characteristics and physical fitness parameters according to playing positions and to identify the relation between body composition and physical fitness in professional soccer players at the beginning of the preparation period. Sixteen professional soccer players participated in this study. Body composition was evaluated by air displacement plethysmography instrumentation (BOD POD®) and physical fitness with specific tests: Running Anaerobic Sprint Test (RAST), Counter Moviment Jump (CMJ), Squat Jump (SJ) and Abalakov jump (ABK), Yo-yo Intermittent Recovery Level 1 (Yo-yo IR1), agility test and flexibility. Kruskal Wallis test demonstrated no significant difference in all estimated body composition, age, height and physical fitness parameters according to three playing positions (p < 0.05). We verified a significant negative correlation between body fat percentage and the performance of CMJ, SJ, ABK, peak, mean and minimum power (-.51 to -.87) and a significant positive correlation with the agility parameter (r = .85). Regarding to lean mass percentage, a significant positive correlation was found with performance of CMJ, SJ, ABK and peak, mean and minimum power (.51 to -.82) and significant negative correlation with agility parameter (r = -.85). Based on the results, we concluded that at the beginning of a pre-season a higher body fat percentage is associated with a negative influence in physical fitness, thus confirming that a greater amount of lean mass percentage is positively associated with the initial level of physical fitness of professional soccer players. Resumén: El objetivo del studio fue comparar las características de los jugadores y los parâmetros de aptitud física según las posiciones de juego e identificar la relación entre la composición corporal y la aptitud física em futebolistas profisionales al inicio del período de preparación. Dieciséis futebolistas profesionales participaron em este estudio. La composición corporal se evaluómediante instrumentación de plestimografia por desplazamiento de aire (BOD POD®) y aptitud física com pruebas específicas: capacidade anaeróbia (RAST), saltos verticales (CMJ, SJ y salto abalakov- ABK), resistência aeróbia, prueba de agilidade y flexibilidad. Kruskal Wallis no demostró diferencias significativas em todos los parâmetros estimados de composición corporal, edad, altura y condición física según las três posiciones de juego (p < 0.05). Verificamos uma correlación negativa significativa entre el porcentaje de grasa corporal y el rendimento de CMJ, SJ, ABK, potencia pico, media y mínima (-.51 to -.87) y uma correlación positiva significativa com el parâmetro de agilidade (r = .85). Em cuanto al porcentaje de massa magra, se encontro uma correlación positiva significativa com el rendimento de CMJ, SJ, ABK y potencia pico, media y mínima (.51 to -.82) y correlación negativa significativa com el parâmetro de agilidade (r = -.85). Com base em los resultados, concluimos que al inicio de una pré-temporada um mayor porcentaje de grassa corporal se associa com uma influencia negativa em la aptitud física, confirmando así que uma mayor porcentaje de massa magra se associa positivamente com el nível inicial de aptitud física de los futebolistas profesionales.

This study aimed to examine which variable, between the peak running velocity determined on the track field (Vpeak_TF) and critical speed (CS), is the best predictor of the 5-km running performance in recreational runners. Twenty-five males performed three tests to determine the Vpeak_TF, CS, and 5-km running performance on the track field, with a minimal interval of 48 h between each test. The Vpeak_TF protocol started with a velocity of 8 km⋅h–1, followed by an increase of 1 km⋅h–1 every 3 min until volitional exhaustion, which was controlled by sound signals, with cones at every 25 m indicating when the participants were required to pass the cone’s position to maintain the required velocity. The participants performed three time trials (TTs) (1: 2,600 m; 2: 1,800 m; and 3: 1,000 m) on the same day, with a 30-min rest period to determine the CS through the combinations of three (CS1,2,3) and two TTs (CS1,2, CS1,3, and CS2,3). The 5-km running performance time was recorded to determine the test duration, and the mean velocity (MV) was calculated. There was a significant difference observed between the Vpeak_TF and the MV 5-km running performance. However, no differences were found between the CS values and the MV 5-km running performance. A correlation was observed between the Vpeak_TF (R = −0.90), CS1,2,3 (R = −0.95), CS1,3 (R = −0.95), and the 5-km running performance time. Linear regression indicated that the Vpeak_TF (R2 = 0.82), CS1,2,3 (R2 = 0.90), and CS1,3 (R2 = 0.90) significantly predicted the 5-km running performance time. The CS results showed a higher predictive power for the 5-km running performance, slightly better than the Vpeak_TF. Also, CS1,2,3 and the CS1,3 presented the highest predictive power for the 5-km running performance of recreational runners.