Physiological responses in futsal have not been studied together with temporal information about the players’ stay on the court. The aim of this study was to compare heart rate (HR) and blood lactate concentration ([La⁻]) responses between 1-H and 2-H considering the time of permanency of the players on the court at each substitution in a futsal match. HR was recorded during entire match and [La⁻] was analyzed after each substitution of seven players. %HR_mean (89.61 ± 2.31 vs. 88.03 ± 4.98 %HR_max) and [La⁻] mean (8.46 ± 3.01 vs. 8.17 ± 2.91 mmol·L⁻¹) did not differ between 1-H and 2-H (ES, trivial-small). Time in intensity zones of 50–100 %HR_max differed only in 60–70 %HR_max (ES, moderate). HR coefficient of variation throughout the match was low (7%) and among the four outfield players on the court (quartets, 5%). Substitutions (2 player’s participation in each half), time of permanence on the court (7.15 ± 2.39 vs. 9.49 ± 3.80 min), ratio between time in- and out-ratio on the court (In:Outcourt = 1:1.30 ± 1:0.48 vs. 1:1.05 ± 1:0.55 min) also were similar between 1-H and 2-H (ES, moderate and small, respectively). Balancing the number of substitutions, and the In:Outcourt ratio of players in both halves of the match, playing lower time at 1-H, ~8 min for each participation in the match, made it possible to maintain intensity of the match in 2-H similar to the 1H. These results are a good guidance to coaches and for application in future studies.

The primary aim of this study was to compare the measured oxygen consumption (Measured-VO₂) in a simulated futsal game (S-Game) with the estimated oxygen consumption (Estimated-VO₂) through a regression equation between heart rate (HR) and oxygen consumption (VO₂) (HR-VO₂) in treadmill running, and a secondary aim was to calculate the total energy expenditure (EE) in S-Game. Ten professional players (22.20 ± 3.22 years) were evaluated. HR-VO₂ was determined individually in the continuous test on the treadmill (Cont_Test). The Measured-VO₂ in S-Game was compared with the Estimated-VO₂ in the Cont_Test. Alactic and lactic pathways were estimated by VO₂. The Estimated-VO₂ presented no statistically significant difference with the Measured-VO₂, using the paired t-test (p = 0.38). However, the correlation between Estimated- and Measured-VO₂ was very weak (r = −0.05), and it presented poor agreement (concordance correlation coefficient = −0.04). In addition, a Bland–Altman plot presented bias of −2.8 ml/kg/min and individual difference as large as 19 ml/kg/min. The HR-VO₂ determined by the Cont_Test was not a good individual predictor of VO₂. The high intensity and intermittent nature of the futsal game possibly caused dissociation in the HR-VO₂ relationship. Cont_Test is not recommended for estimating VO₂ and calculating individual EE in the futsal game. This is recommended only for the group mean. The total EE in S-Game was 13.10 ± 1.25 kcal.min⁻¹ (10.81 ± 1.57 metabolic equivalents). The contributions from the metabolic pathways were as follows: aerobic (93%), alactic (5%), and lactic (2%).

Maximum isometric handgrip strength (MIHS) is a relevant parameter for judo performance and is related to health. Understanding the association between MIHS and MIHS relative (MIHSrel) and the absolute lean mass of the arm (LMarm) and the percentage of body fat (%BF) can provide important information for performance and health. The study aimed to investigate the correlation between MIHS and MIHSrel with the LMarm and the %BF of young judokas (sub-19, 15 males and 14 females). MIHS was measured using a multipurpose digital dynamometer with a load cell for computer. Body composition was measured by dual-energy X-ray absorptiometry (DXA). The correlation between MIHS, MIHSrel with LMarm and %BF was verified through Pearson’s correlation, with a significance level of p < 0.05. Correlation between MIHSrel and %BF was very high only in female judokas for both arms (right, r = −0.76; left, r = −0.75). Correlations between LMarm and MIHS of the right and left arms ranged from very high to almost perfect for both sexes (r = 0.74 to 0.94). These results highlight the importance of strengthening the arms in young judokas, and controlling body fat for performance and health, especially in female judokas.

Objective: To analyze the association between volume and intensity of physical activity and mental health among adolescents. Methods: Cross-sectional study with 604 Brazilian adolescents. Data were assessed using a self-report questionnaire. The outcomes were suicidal ideation, suspicion of common mental disorders, and negative self-perception of mental health. The independent variables were leisure physical activity at low and moderate-to-vigorous intensities. Volume was analyzed in two ways: any volume (presence vs absence), and volume classified according to amount in minutes of weekly physical activity: inactive (0), low active (1–419), and high active (≥420). Poisson regression was performed to estimate prevalence ratios. Results: Any volume of moderate-to-vigorous physical activity was significantly associated with a lower prevalence ratio of all outcomes (PR 0.67 to 0.77). Compared to inactive adolescents, those who were classified as low active for moderate-to-vigorous intensity, presented a lower likelihood of having suicidal ideation, suspicion of common mental disorders, and negative self-perception of mental health (PR 0.70 to 0.76). Furthermore, high active adolescents in moderate-to-vigorous physical activity presented lower suicidal ideation and negative self-perception of mental health (PR 0.62 and 0.57). Conclusions: The promotion of moderate-to-vigorous intensity physical activity at any volume can benefit the mental health of adolescents, however, no association was evidenced for low intensity physical activity.

Introduction: The Relative Age Effect (RAE) encompasses variations associated with the age of athletes within the same category and is present in various sports, including futsal. Objective: This study aimed to compare the RAE in male professional players from the Brazilian National Futsal League (Liga Nacional de Futsal [LNF]) and the Spanish National Futsal League (Liga Nacional de Fútbol Sala [LNFS]), considering differences between native and foreign players. Methodology: The sample consisted of 401 players registered in LNF and 307 in LNFS during the 2020/2021 season. Players were grouped according to their birth quartiles (Q1-Q4) and semesters (S1 and S2). The goodness-of-fit chi-square test (χ2) was used in the statistical analysis of RAE, comparing differences between observed and expected distributions. Cramer’s V was calculated as an effect size measurement. Odds ratios were also calculated for the likelihood of being born in Q1 vs. Q4 and for the first vs. second semester of the year. Results: The main results indicated that RAE was observed only in Brazilian players from the LNF, where players born in Q1 were more frequent than those born in Q3 and Q4. Discussion: Considering the natives and foreigners in the LNFS no deviation from the expected birthdate distribution was observed. Conclusions: Therefore, the conclusion is that RAE is a phenomenon in Brazil's LNF. However, no evidence exists in the LNFS of Spain, whether considering natives or foreigners.

This study aimed to test the reproducibility of the 3-min all-out effort applied using shuttle running and compare its values to aerobic parameters. On the first day, 14 futsal players underwent an exhaustive test to determine the maximal incremental speed (MIS) and anaerobic threshold (AnT). On the second day, the participants performed the 3-min all-out effort (n=14), which was repeated after 48 h (third day) to test its reproducibility (n=11). Peak oxygen consumption (V̇ O2PEAK) and peak blood lactate concentrations ([La-]) were determined from 3-min all-out efforts performed through a 20-m shuttle run on the official court. The distance covered, mean speed, and critical speed (CS) during the 3-min all-out presented direct relationships with aerobic parameters determined through the incremental test (r>0.62). The distance covered above CS (D’) presented a direct relationship with peak lactate concentrations induced by a 3-min all-out effort (r=0.81). Despite the acceptable levels of reproducibility observed for most of the 3-min all-out variables, the minimal detectable change for D’ was high (72%). Our results demonstrated the potential use of mean speed to evaluate aerobic fitness. However, the applicability of the 3-min all-out shuttle run test to monitor training adaptations should be avoided, at least in nonexperienced athletes.