Victor Hugo de Freitas

Effects of additional repeated sprint training during preseason on performance, heart rate variability, and stress symptoms in futsal players: a randomized controlled trial.

Abstract Soares-Caldeira, LF, de Souza, EA, de Freitas, VH, de Moraes, SMF, Leicht, AS, and Nakamura, FY. Effects of additional repeated sprint training during preseason on performance, heart rate variability, and stress symptoms in futsal players: A randomized controlled trial. J Strength Cond Res 28(10): 2815–2826, 2014—The aim of this study was to investigate whether supplementing regular preseason futsal training with weekly sessions of repeated sprints (RS) training would have positive effects on repeated sprint ability (RSA) and field test performance. Thirteen players from a professional futsal team (22.6 ± 6.7 years, 72.8 ± 8.7 kg, 173.2 ± 6.2 cm) were divided randomly into 2 groups (AddT: n = 6 and normal training group: n = 7). Both groups performed a RSA test, Yo-Yo intermittent recovery test level 1 (YoYo IR1), squat (SJ) and countermovement jumps (CMJ), body composition, and heart rate variability (HRV) measures at rest before and after 4 weeks of preseason training. Athletes weekly stress symptoms were recorded by psychometric responses using the Daily Analysis of Life Demands for Athletes questionnaire and subjective ratings of well-being scale, respectively. The daily training load (arbitrary units) was assessed using the session of rating perceived exertion method. After the preseason training, there were no significant changes for body composition, SJ, CMJ, and RSAbest. The YoYo IR1, RSAmean, RSAworst, and RSAdecreament were significantly improved for both groups (p ⩽ 0.05). The HRV parameters improved significantly within both groups (p ⩽ 0.05) except for high frequency (HF, absolute and normalized units, [n.u.]), low frequency (LF) (n.u.), and the LF/HF ratio. A moderate effect size for the AddT group was observed for resting heart rate and several HRV measures. Training load and psychometric responses were similar between both groups. Additional RS training resulted in slightly greater positive changes for vagal-related HRV with similar improvements in performance and training stress during the preseason training in futsal players.

The Activity Profile of Young Tennis Athletes Playing on Clay and Hard Courts: Preliminary Data

Abstract The aim of this study was to compare the kinematic characteristics of tennis matches between red clay and hard courts in young tennis players. Eight young tennis players performed two tennis matches on different court surfaces. The match activities were monitored using GPS units. The distance covered in different velocity ranges and the number of accelerations were analyzed. The paired t test and inference based on magnitudes were used to compare the match physical performance between groups. The total distance (24% of difference), high-intensity running distance (15 - 18 km/h) (30% of difference), the number of high-intensity activities (44% of difference), the body load (1% of difference), and accelerations >1.5 g (1.5-2 g and >2 g 7.8 and 8.1 % of difference, respectively) were significantly greater in clay court than hard court matches (p < 0.05). Matches played on the red clay court required players to cover more total and high-intensity running distances and engage in more high-intensity activities than the matches played on the hard court. Finally, on the clay court the body load and the number of accelerations performed (>1.5 g) were possibly higher than on the hard court.

Monitoramento da carga interna de um período de treinamento em jogadores de voleibol

The aim of this study was to monitor and analyze the dynamics of internal training load using session rating of perceived exertion (session-RPE) method during a training period of volleyball. Twelve volleyball players (23.5 ± 3.4 y, 88.2 ± 11.4 kg, 190.4 ± 10.8 cm) were monitored during 22 training weeks divided into five mesocycles. The ANOVA revealed that the total week training load (TWTL), monotony, and strain were different among the mesocycles (p < 0.05). The higher values of TWTL were showed during mesocycles 2, 4, and 5. Monotony presented values below 1.4 ± 0.1 AU. The mean TWTL of the 22 weeks presented a mean of 1790.9 UA and a coefficient of variation of 16%. The lower and higher mean values of TWTL of the 22 weeks were 1324.3 and 2232.7 UA, respectively. Thus, the internal training load distribution presented moments with higher and lower magnitude between weeks, and increase from 1st to 2nd mesocycle with maintenance of this following others mesocycles.

Seasonal Training Load Distribution of Professional Futsal Players: Effects on Physical Fitness, Muscle Damage and Hormonal Status.

Abstract Miloski, B, de Freitas, VH, Nakamura, FY, de A Nogueira, FC, and Bara-Filho, MG. Seasonal training load distribution of professional futsal players: effects on physical fitness, muscle damage and hormonal status. J Strength Cond Res 30(6): 1525–1533, 2016—The aims of the present study were to describe the training load (TL) distribution of a professional futsal team and verify its subsequent effects on physical performance, muscle damage, and hormonal status. Twelve male professional futsal players (24.3 ± 4.7 years old; 75.5 ± 7.7 kg; and 173.4 ± 4.5 cm) participated in this study. A training program of 22 weeks (6 weeks of pre-season and 16 weeks of in-season) was analyzed. The session rating of perceived exertion method was used to monitor TLs. Physical tests (PTs; countermovement jump (CMJ), 5- and 20-m sprint, T-test, and multistage 20-m shuttle-run tests) were performed 4 times throughout the season (PT1–PT4). Blood sample (BS) collection (Creatine kinase [CK], testosterone, and cortisol) was performed in 7 occasions (BS1–BS7). TLs were higher in pre-season compared to in-season (p < 0.001). Countermovement jumps (CMJs) and 5- and 20-m performances were better in PT3 (CMJ: 0/23/77, 5-m: 0/3/97, and 20-m: 0/1/99) and PT4 (CMJ: 0/8/92, 5- and 20-m: 0/0/100) than in PT1; T-test performance and V[Combining Dot Above]O2max was better in all moments compared with those of PT1 (0/0/100). Higher CK concentration (p = 0.03) and testosterone to cortisol (T:C) ratio values (p = 0.02) were detected in BS2 vs. BS1. An increase in C (p = 0.007) and a decrease in T:C ratio (p = 0.003) was observed from BS4 to BS5. The training program demonstrated higher TLs during the periods with low incidence of matches, emphasis on endurance and strength training during pre-season, speed and power training throughout in-season. This TL organization provides sufficient stimulus for appropriate physical fitness development in professional futsal players, without causing negative disturbances.

Match Analysis and Physical Performance of High-Level Young Tennis Players in Simulated Matches: A Pilot Study

Match Analysis and Physical Performance of High-Level Young Tennis Players in Simulated Matches: A Pilot Study Objective: The aims of this study were to compare the kinematic characteristics of young tennis players at different competitive levels and to analyze the correlation between the Hit and Turn Tennis Test (HTTT) performance and the locomotor performance indices during tennis matches. Methods: Six national level and six regional level tennis players performed the HTTT and a tennis match. The match activities were monitored using GPS units. The distance covered in different speed zones and the numbers of accelerations were analyzed. The inference based on magnitudes was used to compare the match physical performance between groups. Results: The total distance (2716.7 ± 203.3 m vs. 1988.5 ± 346 m), high intensity running distance (42.7 ± 30.6 m vs. 11.8 ± 8.7 m), number of high intensity activities (20.8 ± 12.1 vs. 5.3 ± 4.8) and accelerations >1.5 g were greater in national level than in regional level players. The HTTT was moderately to highly correlated (Spearman’s test) to the total distance covered and the distance covered >15 km/h, and to accelerations >1.5 g. Conclusion: The present study showed that young tennis players of national level performed better than regional level ones during matches. In addition, the HTTT performance was positively correlated with match physical performance, evidencing its validity in tennis.

Efeitos do treinamento sobre variaveis psicofisiologicas na pre-temporada de futebol

OBJETIVO: Verificar o efeito da carga de treinamento em variaveis bioquimicas, psicologicas, fisiologicas e hematologicas durante uma pre-temporada em atletas profissionais de futebol. METODOS: Oito jogadores de futebol profissional foram monitorados por 21 dias durante uma pre-temporada e submetidos a quatro avaliacoes (T1, T2, T3 e T4). As variaveis analisadas foram: concentracao de hemoglobina, creatina quinase, questionario POMS e variabilidade da frequencia cardiaca no dominio do tempo e da frequencia. A carga de treinamento de cada sessao foi quantificada atraves do metodo TRIMP. RESULTADOS: A creatina quinase aumentou significativamente (p 0,05) e nao foram encontradas correlacoes entre as variaveis. CONCLUSAO: Parece que a creatina quinase e a variavel mais sensivel a carga de treinamento do que as outras analisadas. Os valores da variabilidade da frequencia cardiaca no dominio da frequencia apresentam uma tendencia na resposta para mudancas na carga de treinamento.o bjective: t o verify the effect of training load in biochemical, psychological, physiological and hematological variables during a pre-season in professional soccer players. methods: Eight male professional soccer players were monitored for 21 days during a pre-season and submitted to four evaluations ( t 1, t 2, t 3 and t4). t he variables analysed were: hemoglobin, creatine kinase, poms questionnaire and heart rate variability in time and frequency domains. t he load of each training session was quantified using the trimp method. r esults: creatina kinase increased significantly (p 0.05) and no correlations between variables were found. c onclusion: i t seems that creatina kinase is the most sensitive variable to training load compared to the other variables. heart rate vari -

Effect of cold water immersion performed on successive days on physical performance, muscle damage, and inflammatory, hormonal, and oxidative stress markers in volleyball players.

Abstract de Freitas, VH, Ramos, SP, Bara-Filho, MG, Freitas, DGS, Coimbra, DR, Cecchini, R, Guarnier, FA, and Nakamura, FY. Effect of cold water immersion performed on successive days on physical performance, muscle damage, and inflammatory, hormonal, and oxidative stress markers in volleyball players. J Strength Cond Res 33(2): 502–513, 2019—The aim of this study was to investigate the effects of daily cold water immersion (CWI) on physical performance, muscle damage, and inflammatory, hormonal, and oxidative stress markers in volleyball. Six players were submitted to CWI and six players to a placebo, during 5 training days. Thigh circumference, squat jump, and agility were measured on the first, third, and sixth days. On the first and sixth days, blood and saliva were collected for analysis of oxidative stress, muscle damage, and inflammatory and hormonal levels. Muscle soreness and countermovement jump were quantified daily. The physical performance comparisons did not present differences and the only between group comparison with a large effect size (ES = −1.39) was in &Dgr;% between day 1 and day 2 for countermovement jump. Delayed onset muscle soreness and creatine kinase increased in both groups and the ESs of between group comparisons of &Dgr;% between moments were not more than moderate. Thigh circumference increased only in the placebo group (p = 0.04) and the ES of the between group comparisons of &Dgr;% between moments was large (1.53). No differences were found in oxidative stress, or inflammatory markers. Cortisol decreased only in the CWI-group (p ⩽ 0.05) and the ESs of the between group comparisons of &Dgr;% between moments of the testosterone to cortisol ratio (−1.94) and insulin-like growth-1 (−1.34) were large. Despite the positive effects of daily CWI on muscle edema and hormonal status, the limited effects of CWI on performance, muscle damage, inflammation markers, and reactive oxygen species mediators signal the unimportance of the daily practice of this recovery method in volleyball players.

Relationship Between Training Volume and Ratings of Perceived Exertion in Swimmers.

The markers of external training load (ETL), distance and intensity, do not take into account the athletes’ psychophysiological stress, i.e., internal training load (ITL). Thus, the aim of this study was to evaluate the relationship between ETL and ITL using the rating of perceived exertion (RPE) and session-RPE in swimmers. Seventeen young swimmers (10 male, 15.8 ± 0.87 yr and 7 female, 15.1 ± 0.46 yr) belonging to one national level youth team took part in this study over 4 wk. The external training load was planned using swimming distance (in meters) at seven different training intensities. Swimmers’ RPE was assessed 30 min after each training session. Session-RPE was calculated by multiplying RPE by session duration (min). The relationship between the variables was analyzed with Pearson correlations and a multiple linear regression was performed to predict the session-RPE as a function of the independent variables (aerobic and anaerobic volume). The swimming distance at different intensities correlated strongly with RPE and very largely with session-RPE (.64, p < .05 and .71, p < .05, respectively). Regression analysis indicated that the aerobic and anaerobic volumes together explained more than 50% of the ITL variability. In conclusion, the swimming distance in each training session was significantly associated with RPE and session-RPE in swimmers. In other words, based on these results, the use of high-volume training at lower intensities affects the RPE and Session-RPE more than the anaerobic volume.

Validation of the futsal-specific intermittent shuttle protocol for the simulation of the physical demands of futsal match-play

Abstract The aim of this study was to analyse the impact of a futsal-simulated match (SM) and futsal-specific intermittent shuttle protocol (FISP) on physical performance, and muscle damage, inflammation, and oxidative stress markers immediately and 24 h post protocols. Thirteen, male, U-20 futsal players performed the FISP and the SM on two different occasions. Heart rate (HR) and rating of perceived exertion (RPE) were monitored during both protocols with countermovement jump (CMJ), perceived muscle soreness, and blood samples measured Pre, Post, and 24 h post protocols. Player’s HR was not significantly different between FISP and SM (p > .05) with RPE significantly higher during the FISP (p < .05). Player’s CMJ for FISP and SM (p < .05) decreased at Post and 24 h compared with Pre, without significant increases in perceived muscle soreness, interleukin-6, tumour necrosis factor-α, carbonylated proteins and advanced products of protein oxidation (AOPP) at 24 h (p > .05). Creatine kinase (CK) increased 24 h for SM (p < .05). The chances of FISP being different from SM were very likely for CK and AOPP 24 h and unclear for other variables. The results found demonstrated the FISP as a valid simulator of futsal match demands.

Efectos del entrenamiento en las variables psicofisiologicas en pretemporada de futbol

OBJETIVO: Verificar o efeito da carga de treinamento em variaveis bioquimicas, psicologicas, fisiologicas e hematologicas durante uma pre-temporada em atletas profissionais de futebol. METODOS: Oito jogadores de futebol profissional foram monitorados por 21 dias durante uma pre-temporada e submetidos a quatro avaliacoes (T1, T2, T3 e T4). As variaveis analisadas foram: concentracao de hemoglobina, creatina quinase, questionario POMS e variabilidade da frequencia cardiaca no dominio do tempo e da frequencia. A carga de treinamento de cada sessao foi quantificada atraves do metodo TRIMP. RESULTADOS: A creatina quinase aumentou significativamente (p 0,05) e nao foram encontradas correlacoes entre as variaveis. CONCLUSAO: Parece que a creatina quinase e a variavel mais sensivel a carga de treinamento do que as outras analisadas. Os valores da variabilidade da frequencia cardiaca no dominio da frequencia apresentam uma tendencia na resposta para mudancas na carga de treinamento.o bjective: t o verify the effect of training load in biochemical, psychological, physiological and hematological variables during a pre-season in professional soccer players. methods: Eight male professional soccer players were monitored for 21 days during a pre-season and submitted to four evaluations ( t 1, t 2, t 3 and t4). t he variables analysed were: hemoglobin, creatine kinase, poms questionnaire and heart rate variability in time and frequency domains. t he load of each training session was quantified using the trimp method. r esults: creatina kinase increased significantly (p 0.05) and no correlations between variables were found. c onclusion: i t seems that creatina kinase is the most sensitive variable to training load compared to the other variables. heart rate vari -