Perceived training load and jumping responses following nine weeks of a competitive period in young female basketball players

The aims of this study were to describe the session rating of perceived exertion (sRPE), total quality recovery (TQR), and variations in countermovement jump (CMJ) height throughout nine weeks of a competitive period in young female basketball players. In total, 10 young female basketball players (17.2 ± 0.4 years; 71.8 ± 15.0 kg; 177.2 ± 9.5 cm) participated in this study. The sRPE and TQR were assessed in each training session, whereas the CMJ height was assessed prior to the first weekly training session. The magnitude-based inferences method was used to compare the sRPE, TQR, and CMJ height across the nine weeks of training. The training loads accumulated in weeks 1, 2, and 3 were likely to almost certainly be higher than in the following weeks (ES varying from 0.67 to 2.55). The CMJ height in week 1 was very likely to be lower than in weeks 2, 5, 7, and 8 (ES varying from 0.24 to 0.34), while the CMJ height of the 9th week was likely to almost certainly be higher than all previous weeks of training (ES varying from 0.70 to 1.10). Accordingly, it was observed that when higher training loads were accumulated, both CMJ and TQR presented lower values than those presented during periods with lower internal training loads. These results highlight the importance of using a comprehensive and multivariate approach to effectively monitor the physical performance of young athletes

Post-activation potentiation: is there an optimal training volume and intensity to induce improvements in vertical jump ability in highly-trained subjects?

The aim of this study was to compare the acute effects of performing half squats (HSs) with different loading intensities (1, 3, and 5 repetitions maximum [RM], and 60% 1RM) and a different number of sets (1, 2, and 3) on the countermovement jump (CMJ) performance of 18 highly-trained male subjects. Participants were submitted to four experimental conditions (1RM, 3RM, 5RM, and 60% 1RM) in randomized order. The CMJ was assessed before and after each set. Differences in CMJ performance between the distinct experimental conditions and individual responses in CMJ performance induced by the different protocols were analyzed via the magnitude-based inference method. Overall, significant improvements were detected in individual CMJ heights after each activation protocol. It can be concluded that the use of 1 to 3 sets of HSs performed at moderate-to-high loads may be an effective strategy to improve jump performance in highly-trained subjects. Nevertheless, despite the high efficiency of the protocols tested here, coaches and researchers are strongly encouraged to perform individualized assessments within the proposed range of loads and sets, to find optimal and tailored post-activation potentiation protocols

A new bioavailable fenretinide formulation with antiproliferative, antimetabolic, and cytotoxic effects on solid tumors.

Fenretinide is a synthetic retinoid characterized by anticancer activity in preclinical models and favorable toxicological profile, but also by a low bioavailability that hindered its clinical efficacy in former clinical trials. We developed a new formulation of fenretinide complexed with 2-hydroxypropyl-beta-cyclodextrin (nanofenretinide) characterized by an increased bioavailability and therapeutic efficacy. Nanofenretinide was active in cell lines derived from multiple solid tumors, in primary spheroid cultures and in xenografts of lung and colorectal cancer, where it inhibited tumor growth independently from the mutational status of tumor cells. A global profiling of pathways activated by nanofenretinide was performed by reverse-phase proteomic arrays and lipid analysis, revealing widespread repression of the mTOR pathway, activation of apoptotic, autophagic and DNA damage signals and massive production of dihydroceramide, a bioactive lipid with pleiotropic effects on several biological processes. In cells that survived nanofenretinide treatment there was a decrease of factors involved in cell cycle progression and an increase in the levels of p16 and phosphorylated p38 MAPK with consequent block in G0 and early G1. The capacity of nanofenretinide to induce cancer cell death and quiescence, together with its elevated bioavailability and broad antitumor activity indicate its potential use in cancer treatment and chemoprevention

Short-term calorie restriction enhances adult hippocampal neurogenesis and remote fear memory in a Ghsr-dependent manner

The beneficial effects of calorie restriction (CR) have been described at both organismal and cellular levels in multiple organs. However, our understanding of the causal mediators of such hormesis is poorly understood, particularly in the context of higher brain function. Here, we show that the receptor for the orexigenic hormone acyl-ghrelin, the growth hormone secretagogue receptor (Ghsr), is enriched in the neurogenic niche of the hippocampal dentate gyrus (DG). Acute elevation of acyl-ghrelin levels by injection or by overnight CR, increased DG levels of the neurogenic transcription factor, Egr-1. Two weeks of CR increased the subsequent number of mature newborn neurons in the DG of adult wild-type but not Ghsr−/− mice. CR wild-type mice also showed improved remote contextual fear memory. Our findings suggest that Ghsr mediates the beneficial effects of CR on enhancing adult hippocampal neurogenesis and memory

Effects of combined strength and plyometric training on technic, tactic and strategic volleyball game actions

O objetivo desse trabalho foi observar se as ações de jogo de voleibol (i.e., saque, recepção, levantamento, ataque, bloqueio, defesa), as ações consecutivas e os complexos de jogo (KI e KII) alteram-se com aumentos de força e potência muscular. Vinte e oito jogadoras amadoras de duas equipes diferentes dividiram-se em grupo controle (GC) e experimental (GE), sendo GE submetido a oito semanas de treinamento de força e pliometria (TC) para membros inferiores e superiores. Foram realizados testes de força dinâmica máxima (agacha-mento e supino), T de agilidade modificado, arremesso de medicinebol, salto vertical com contramovimento, força reativa e potência (agachamento com salto e supino com arremesso da barra),e essas variáveis foram denominadas motoras. As ações de jogo foram denominadas de variáveis técnico-tática-estratégicas e foram analisadas quanto à frequência absoluta, relativa e efetividade. Observaram-se melhoras de GE para 1RM no agachamento e supino, tempo do teste T modificado, potência pico de membros superiores e distância no arremesso de medicinebol, com aumento significante desta última também para GC (p0,05) em nenhuma das variáveis motoras. Para as varáveis técnico-tática-estratégicas, os efeitos do TC para GE, em relação a GC, parecem influenciar o tipo de levantamento de um modo geral e após uma ação, o tipo de ataque após uma ação, o tempo de ataque, a quantidade de bloqueadores e o tipo de defesa com deslocamentos, assim como, ao considerar a combinação de ações consecutivas, pareceram influenciar o tipo de levantamento nas diferentes zonas de levantamentos após a recepção e a defesa, as inversões do levantamento para maiores distâncias após a recepção e a defesa, bem como a quantidade de bloqueadores para os ataques de bolas mais altas e para as bolas intermediárias, a defesa para os ataques sem bloqueios e com bloqueios simples e as defesas para os ataques mais rápidos. Em relação aos complexos de jogo, ainda, os efeitos do TC pareceram influenciar o tipo e o tempo de ataque quando as recepções são realizadas com deslocamento no complexo I, enquanto no complexo II, pareceram influenciar os tempos de ataque quando a equipe que contra-ataca tem a posse do saque, bem como o tipo e o tempo dos contra-ataques que tiveram início com defesa com deslocamento. Por fim, a efetividade das ações de jogo pareceu ser pouco influenciada pelas alterações induzidas pelo TC, com pequenos aumentos para o levantamento e bloqueio. A inclusão do TC ao treinamento específico exerce pouca influência sobre o desempenho técnico-tático-estratégico de jogadoras de voleibol amadoras. Entretanto, este foi o primeiro estudo a investigar tal relação, de modo que, pesquisas adicionais e a busca por meios de avaliação capazes de identificar de modo objetivo e preciso as alterações físicas num contexto específico do jogo são necessáriosThe aims of this study were test if performance in volleyballs skills (i.e. service, re-ception, set, spike, block and dig), as well as their combinations and game phases (side out and side out transition), are influenced by muscle power improvements achieved with a com-bined training (CT). Twenty-eight amateurs volleyball players from two different teams par-ticipated on this study. Players were assigned to either a control (CG;n=14) or training (TG;n=14) group. TG performed eight weeks of CT, twice a week, using plyometric and tra-ditional strength exercises for both the lower and upper limbs. Both groups maintained their technical-tactical training routines. Motor (1RM squat and bench press, time on agility T modified test, medicineball throw distance, countermovement jump height (CMJ), reactive strength index (RSI), and peak power in jump squat and bench throw exercises) and sport-specific performance(game analysis) were accessed before and after experimental protocol. Squat and bench press 1RM, agility T test-time, bench throw-peak power and medicineball throw distance improved for the TG (p0,05). It seems that TG had improved and changed the type of set, type and time of attacks, number of blockers and getting behind the ball to dig. Actions game combinations seemed have improved also, especially type of set from different set zones after reception and dig, sets to the farthest distances, attacks in oppo-sition to two players blocks and number of blockers to high balls, as well as digs to attacks without block, with a single player block and after ball touches block and digs for quick at-tacks also. Besides, it seems that TG had improved their type and time of attacks in KI when they were initiated with receptions after displacements, and time of attacks in KII when teams were serving, as well as when they were initiated with dig after displacements. Finally, total game actions effectiveness was little or no influenced by increasing strength and power per-formances. Since this was the first research that had investigated if increasing strength and power output also improve sport specific performances, additional researches are necessary, as well as an instrument which measures precisely and objectively the alterations in games actions in a game specific context must be searc

Mixed Training Methods: Effects of Combining Resisted Sprints or Plyometrics with Optimum Power Loads on Sprint and Agility Performance in Professional Soccer Players

The aim of this study was to compare the effects of two different mixed training programs (optimum power load [OPL] + resisted sprints [RS] and OPL + vertical/horizontal plyometrics [PL]) on neuromuscular performance of elite soccer players during a short-term training preseason. Eighteen male professional soccer players took part in this study. The athletes were pair-matched in two training groups: OPL + RS and OPL + PL. Unloaded and resisted sprinting speeds at 5-, 10-, 20-, and 30-m, change of direction (COD) speed, and performance in the squat jump (SJ), countermovement jump (CMJ), and horizontal jump (HJ) were assessed pre- and post- a 5-week training period. Magnitude based inference with the effect sizes were used for data analysis. A possible increase in the SJ and CMJ heights and a likely increase in the HJ distance were observed in the OPL + PL group. Meaningful improvements were observed in the COD speed test for both training groups comparing pre- and post-measures. In both unloaded and resisted sprints, meaningful decreases were observed in the sprinting times for all distances tested. This study shows that a mixed training approach which comprises exercises and workloads able to produce positive adaptations in different phases of sprinting can be a very effective strategy in professional soccer players. Moreover, the possibility of combining optimum power loads with resisted sprints and plyometrics emerges as a novel and suitable option for coaches and sport scientists, due to the applicability and efficiency of this strength-power training approach

Loaded and unloaded jump performance of top-level volleyball players from different age categories

The aim of this study was to investigate the differences in loaded and unloaded jump performances between different age categories of top-level volleyball players from the same club. Forty-three volleyball players were divided into four age groups: under-17, under-19, under-21 and professional. Vertical jumping height for squat jump (SJ), countermovement jump (CMJ) and CMJ with arm swing (CMJa) and mean propulsive velocity (MPV) in the loaded jump squat exercise with 40% of the athlete’s body mass were compared among the different age categories, considering body mass as a covariate. SJ and CMJ jump height values were higher for professional and under-21 players than under-17 players (p<0.05). CMJa height was higher for under-21 players than under-19 and under-17 players (p<0.05). MPV in the loaded jump squat was higher for under-21 players than under-17 players (p<0.05). From a general perspective, these results suggest that aging per se is not capable of substantially improving loaded and unloaded vertical jump performances across different age categories of top-level volleyball players. Therefore, to increase the vertical jumping ability of these team sport athletes throughout their long-term development, coaches and strength and conditioning professionals are encouraged to implement consistent neuromuscular training strategies, in accordance with the specific needs and physiological characteristics of each age group

Jump-Squat and Half-Squat Exercises: Selective Influences on Speed-Power Performance of Elite Rugby Sevens Players.

The aim of this study was to evaluate the relation between the maximum mean propulsive power (MPP) obtained in the loaded jump squat (JS) and half squat (HS) exercises and functional performances in vertical jumps, 40 m linear speed (VEL) and change-of-direction (COD) tests, using the median split technique. Twenty-two male rugby sevens players from the Brazilian National Olympic Team (Rio-2016) performed vertical jumping tests (squat and countermovement jumps [SJ and CMJ]), JS and HS exercises, COD speed test and sprinting velocity in 40 m, in this order. Based on the results of the MPP in the JS and HS exercises the participants were divided, using the median split, into four groups as follows: higher JS, lower JS, higher HS, and lower HS. Between-group differences in the functional tasks were detected via magnitude-based inferences. The athletes with higher MPP in the JS were capable of jumping higher and sprinting faster (including the COD speed test) than their weaker counterparts. This pattern was not observed in the HS exercise. To conclude, JS was shown to be more connected to sprinting, COD speed and jumping abilities than HS in elite rugby sevens players and should be preferred for assessing and possibly training elite athletes needing to improve speed-power related abilities