The purpose of this study was to analyze systolic blood pressure (SBP), diastolic blood pressure (DBP) and the heart rate (HR) before, during and after training at moderate intensity (MI, 50%-1RM) and at low intensity with blood flow restriction (LIBFR). In a randomized controlled trial study, 14 subjects (average age 45±9,9 years) performed one of the exercise protocols during two separate visits to the laboratory. SBP, DBP and HR measurements were collected prior to the start of the set and 15, 30, 45 and 60 minutes after knee extension exercises. Repeated measures of analysis of variance (ANOVA) were used to identify significant variables (2 × 5; group × time). The results demonstrated a significant reduction in SBP in the LIBFR group. These results provide evidence that strength training performed acutely alters hemodynamic variables. However, training with blood flow restriction is more efficient in reducing blood pressure in hypertensive individuals than training with moderate intensity.

Water-based exercise and low-intensity exercise in combination with blood flow restriction (BFR) are two methods that have independently been shown to improve muscle strength in those of advancing age. The objective of this study was to assess the long-term effect of water-based exercise in combination with BFR on maximum dynamic strength and functional capacity in post-menopausal women. Twenty-eight women underwent an 8-week water-based exercise program. The participants were randomly allocated to one of the three groups: (a) water exercise only, (b) water exercise + BFR, or (c) a non-exercise control group. Functional capacity (chair stand test, timed up and go test, gait speed, and dynamic balance) and strength testing were tested before and after the 8-week aquatic exercise program. The main findings were as follows: (1) water-based exercise in combination with BFR significantly increased the lower limb maximum strength which was not observed with water-based exercise alone and (2) water-based exercise, regardless of the application of BFR, increased functional performance measured by the timed up and go test over a control group. Although we used a healthy population in the current study, these findings may have important implications for those who may be contraindicated to using traditional resistance exercise. Future research should explore this promising modality in these clinical populations.

The present study aimed to analyse the effects of six weeks of strength training (ST), with and without blood flow restriction (BFR), on torque, muscle activation, and local muscular endurance (LME) of the knee extensors. Thirty-seven healthy young individuals were divided into four groups: high intensity (HI), low intensity with BFR (LI+BFR), high intensity and low intensity + BFR (COMB), and low intensity (LI). Torque, muscle activation and LME were evaluated before the test and at the 2nd, 4th and 6th weeks after exercise. All groups had increased torque, muscle activation and LME (p<0.05) after the intervention, but the effect size and magnitude were greater in the HI, LI+BFR and COMB groups. In conclusion, the groups with BFR (LI+BFR and COMB) produced magnitudes of muscle activation, torque and LME similar to those of the HI group.

Strength training combined with blood flow restriction (BFR) have been used to improve the levels of muscle adaptation. The aim of this paper was to investigate the acute effect of high intensity squats with and without blood flow restriction on muscular fatigue levels. Twelve athletes (aged 25.95 ± 0.84 years) were randomized into two groups: without Blood Flow Restriction (NFR, n = 6) and With Blood Flow Restriction (WFR, n = 6) that performed a series of free weight squats with 80% 1-RM until concentric failure. The strength of the quadriceps extensors was assessed in a maximum voluntary isometric contraction integrated to signals from the surface electromyogram. The average frequency showed significant reductions in the WFR group for the vastus lateralis and vastus medialis muscles, and intergroup only for the vastus medialis. In conclusion, a set of squats at high intensity with BFR could compromise muscle strength immediately after exercise, however, differences were not significant between groups.

Abstract The production of litterfall is essential for nutrient cycling in terrestrial ecosystems. From November 2009 to October 2011, analyzed the monthly litterfall production in two areas of Caatinga, a type of Seasonally Dry Tropical Forest located in the Cariri Paraibano, in the semiarid region of the Paraíba, Northeastern Brazil. One of the areas, Private Natural Heritage Reserve (RPPN) Fazenda Almas, is legally protected, and the other, Fazenda Moreiras, does not. The aims were to evaluate the effects of precipitation, evapotranspiration and vegetation structure on the temporal and spatial dynamics of litterfall production. Eight sampling points were randomly chosen at each site, and two 1 m2 collectors were installed 50 m apart from each other. The collected material was sorted, dried and weighed. Additionally, the characteristics (density, species richness, height and mean basal area) of the tree-shrub stratum in plots with a 10 m radius surrounding each collector. Total litterfall production was 4,500 kg ha-1 yr-1 for Fazenda Almas and 3,300 kg ha-1 yr-1 for Fazenda Moreiras; these values were within the expected range for Seasonally Dry Tropical Forests. The inter- and intra-annual variation in litterfall production was positively correlated with precipitation and evapotranspiration rates, and four months after the highest precipitation rates, there was a marked decrease in litterfall occurred during the dry season. Furthermore, the contributions of the material fractions were distinct with the leaf fraction representing for more than 60% of the litterfall, and the vegetation structure explained 75% of the variation in litterfall production. Therefore, climatic factors and vegetation structure affect the temporal and spatial dynamics of litterfall production and consequently influence nutrient dynamics in the semiarid region of Brazil.

ARTIGO ORIGINAL | ORIGINAL ARTICLE RESUMOO objetivo do presente estudo foi verificar o efeito agudo do exercício predominantemente aeróbico (EA) com restrição de fluxo sanguíneo (RFS) sobre a pressão arterial sistólica (PAS), pressão arterial diastólica (PAD) e frequência cardíaca (FC) em jovens saudáveis. Participaram do estudo 13 universitários normotensos (19.5 ± 1.7anos). Os participantes foram divididos randomicamente em duas sessões experimentais (cross-over): a) exercício aeróbico com a RFS (EARFS); b) exercício aeróbico sem a RFS (EASRFS). As sessões foram realizadas com cinco séries de dois minutos e um minuto de intervalo. A PAS, PAD e FC foram mensurados em repouso, no final dos exercícios e durante os 60 minutos pós-exercício. O EASRFS apresentou efeito hipotensivo no 60º pós-exercício (p= 0.029); o EA com e sem RFS elevou significativamente a PAS e FC imediatamente após o exercício (p< 0.05), e o EARFS apresentou valores de PAD e FC superiores, no momento imediatamente pós-exercício, quando comparado com o EASRFS (p= 0.001; p< 0.001, respectivamente). Conclui-se, que o EARFS parece não maximizar o efeito hipotensivo, ambos as sessões podem elevar a PAS e FC imediatamente pós-exercício com valores significativos maiores na PAD e FC para o EARFS. Palavras-chave: hemodinâmica, oclusão vascular, exercício, efeito hipotensivo. ABSTRACTThe aim of the present study was to verify the acute effect of the aerobic exercise (AE) with blood flow restriction (BFR) upon systolic (SBP), diastolic blood pressure (DBP) and heart rate (HR) in health youngsters. Participated in the present study 13 young normotensive students (19.5 ± 1.7 years old). The sample was randomly divided into two experimental protocols: stationary race with BFR and stationary race without BFR. Subjects performed 5 sets of 2 minutes with 1 minute of rest interval for both protocols. SBP, DBP and HR were measured at rest, in the end of the exercises and during 60 minutes after conditions. The AE without BFR presented hypotensive effect 60 minutes post exercise (p= 0.029); the AE with and without BFR elevated significantly the SBP and HR immediately post exercise (p< 0.05) and the AE with BFR presented higher DBP and HR values immediately post-exercise when compared to AE without BFR (p= 0.001; p< 0.001, respectively). It is concluded that the AE without BFR does not seem to maximize the hypotensive effect, both sessions can increase SBP and HR immediately post-exercise with significant higher values in DBP and HR for AE with BFR.

ARTIGO ORIGINAL | ORIGINAL ARTICLE RESUMOO objetivo do estudo foi identificar e comparar os indicadores de rendimento técnico-tático em função do resultado do set no voleibol feminino escolar. Participaram do estudo 110 atletas, com faixa etária entre 12 a 14 anos, pertencentes a 11 equipes. Foram filmados 58 sets de 28 jogos, e analisados 7194 ações, sendo 2830 saques, 2157 recepções de saque, 1358 levantamentos e 1299 ataques. Em seguida, os sets dos jogos foram agrupados em sets vencedores e perdedores. As equipes que venceram os sets obtiveram vantagem na recepção de saque, no levantamento e no ataque nos critérios de erro e excelência/ponto (p< 0.05) e na qualidade nos coeficientes de levantamento, de saque e de ataque (p< 0.001). Em conclusão, os sets vencedores foram os que apresentaram melhor desempenho técnico-tático de forma quantitativa e qualitativa. Palavras-chave: voleibol, análise de jogo, esportes coletivos ABSTRACTThe aim of the study was to identify and compare the technical and tactical performance indicators based on the outcome of the set in the school female volleyball. The study included 110 athletes, aged between 12 and 14 years, belonging to 11 teams. Fifty-eight sets of 28 games were filmed and 7194 actions, 2830 serves, 2157 serve reception, 1358 passes and 1299 attacks were analyzed. Afterwards, the game sets were divided into winners and losers sets. Teams that won the sets had advantage at the serve reception, set and attack on error and excellence/point criteria (p< 0.05) and of serve, set and attack (p< 0.001). In conclusion, the winner's sets were those with a better technical-tactical performance quantitatively and qualitatively.

Introduction: No research has investigated predictive equations for application in blood flow restriction (BFR) training using a cuff with a circumference of 18 cm for the lower limbs, and including age and sex as predictor variables. Objectives: To develop an equation to predict cuff pressure levels for use in BFR training for the lower limbs. Methods: A total of 51 adults (age 23.23 ± 5.24 years) of both sexes (males, n= 32; females, n= 19) underwent a series of tests and anthropometric (body mass, height, body mass index -BMI, and thigh circumference -TC) and hemodynamic (brachial systolic -SBP -and diastolic -DBP -blood pressure) measurements. The arterial occlusion pressure (AOP) of the lower limbs was measured using a Doppler probe. Results: The predictive equation was developed based on a hierarchical linear regression model consisting of six blocks, corresponding to TC (β = 0.380; p = 0.005), SBP (β = 0.091; p = 0.482), age (β = 0.320; p = 0.015), and sex (β = -0.207; p = 0.105), which explained 39.7% of the variation in arterial occlusion pressure. DBP and BMI were not associated with AOP. As a result, the predictive equation is as follows: AOP (mmHg) = 65.290 + 1.110 (TC in cm) + 0.178 (SBP in mmHg) + 1.153 (age in years) -7.984 (sex, 1 -male and 2 -female), reporting values of r = 0.630, r 2 = 0.397 and SEE = 15,289. Conclusion: Cuff pressure for BFR training of the lower limbs may be selected based on TC, SBP, age and sex, and thigh circumference is considered the main predictor. Level of Evidence III, Non-consecutive studies, or studies without consistently applied reference standard.