Is There a Relationship Between Birth Quartile and Vertical Jump Performance Among Young Male Elite Volleyball Athletes?

Vertical jump is an important skill that influences volleyball performance. In this study, we analyzed the relationship between vertical jump performance and birth quartile of Brazilian male youth volleyball players. We calculated chi-square goodness-of-fit tests to compare the athletes' birthdate distributions in quarters of their birth years (Q1, Q2, Q3, and Q4) according to player age categories (U17, U18, U19, and U21). We calculated one-way ANOVAs to compare spike jump and block jump heights of players born in different quarters of the same year. Overall, we found a relative age effect (i.e., more players with birth dates early in the birth year) in U17 (p < .001), U18 (p < .001), U19 (p < .001), and U21 (p = .04). Regarding vertical jump performance, U18 athletes born in Q2 reached higher spike jump heights (p = .006) and block jump heights (p = .002) than athletes born in Q4, and U19 athletes born in Q1 reached higher block jump heights than athletes born in Q3 (p = .049). There were no significant differences in vertical jump performance across birth quartiles among U17 and U21 athletes. Thus, a relative age effect was present in all age categories but not always reflected in vertical jump performance. Volleyball coaches and policymakers are still advised to employ strategies to ensure fairer opportunities for players born later in the year of their eligibility dates, as we found RAE to be sometimes, but not always, related to higher spike or block jump heights even among these older adolescents and young adult athletes.

Patterns and management of musculoskeletal injuries in attempted suicide by jumping from a height: a single, regional level I trauma center experience.

BACKGROUND: Suicide is a common cause of death in Brazil, with an overall increase of 62.5% during the last 30-year period. The study aims to determine overall patient characteristics and symptomatic indicators of complications among survivors. METHODS: In this retrospective cross-sectional study, we collected and analyzed clinical information of all patients aged > 10 years who presented to our hospital with a history of attempted suicide by jumping from a height in a 7-year period. Records were searched for primary demographic data, radiographs and CT scans were reviewed to determine injury characteristics, and records and operative notes were searched to look for symptomatic indicators of complications among survivors. Baseline demographics and the distribution on skeletal injuries were compared between the survivor and non-survivor patients using the Chi-squared for categorical variables and the Student's t-test for continuous variables. Among survivors, univariate and multivariate analysis were performed to investigate independent risk factors of attempted suicide and complications. RESULTS: A total of 222 patients attempted suicide by jumping from a height. At multivariate analysis, the middle-aged patient was the unique identified risk factor for suicide by jumping from a height. Overall mortality was 67.6%. The main independent cause for death was traumatic brain injury. Among survivors, there was a higher incidence of foot and ankle fractures, and pelvic ring injuries. The overall complication rate for survivor patients was 51.4%, with acute infection being the most prevalent complication. At multivariate analysis, middle-aged men, foot and ankle injuries, open pelvic injuries, and open fractures were identified as risk factors for acute complications. CONCLUSION: Middle-aged people are at significant risk for attempting suicide by jumping from a height in Brazil, independently of gender, with 67.6% deaths. Traumatic brain injury, higher ISS, and more than 3 skeletal injuries are independent variables related to this fatal outcome. Acute complications occur in approximately 50% of survivors. Middle-aged men, foot and ankle injuries, open pelvic injuries, and open fractures are risk factors for complications.

Efecto de diferentes tipos de entrenamiento físico en la altura de salto de gimnastas: meta-análisis / Effect of different types of physical training on gymnastics jump height: meta-analysis

Resumen Ulloa-Sánchez, P., y Hernández Elizondo, J. (2021). Efecto de diferentes tipos de entrenamiento físico en la altura de salto de gimnastas: meta-análisis. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(1), 1-35. El principal objetivo del presente estudio fue determinar el efecto de diferentes tipos de entrenamiento físico en la altura de salto de gimnastas bajo la metodología de meta-análisis. Se siguieron los lineamientos PRISMA; las bases de datos electrónicas consultadas en la búsqueda fueron EBSCOhost (SPORTDiscus, MEDLINE, Academic Search Complete, E-Journals, OmniFile Full Text Select (H.W. Wilson), Web of Science, Scopus, SciencDirect, Research Gate y Pubmed para identificar los artículos relevantes que investigaron la aplicación de un entrenamiento físico y evaluaron la altura salto en gimnastas antes y después de la intervención. Después del proceso de selección de estudios, y a partir de los criterios de inclusión, se codificaron 29 estudios individuales y se codificaron 157 tamaños de efecto (TE) individuales. La muestra total de sujetos fue 688 gimnastas. El grupo experimental mostró un TE global de bajo a moderado y significativo (TE = 0.33, . <0 .001*). Se evidenció una diferencia significativa (. = 0.001*) entre los tipos de entrenamiento; el análisis Post Hoc mostró que el TE global del entrenamiento de pliometría (TE = 0.85, . <0.001*) fue mayor al de estiramiento (TE = -0.07, . = 0.56) y "otros" (TE = 0.48, . < 0.001*), pero no al de vibración (TE = 0.54, . < 0.001*); además, el TE global de tipo de estiramiento fue significativamente menor a todos los tipos de entrenamiento. Se concluyó que el tipo de entrenamiento que mostró el mayor TE global fue pliometría, seguido por el entrenamiento en plataforma vibratoria. Parece que el estiramiento no se relaciona significativamente con la altura de salto de gimnastas.

Abstract Ulloa-Sánchez, P., & Hernández Elizondo, J. (2021). Effect of different types of physical training on gymnastics jump height: meta-analysis. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(1), 1-35. The main objective of this study was to determine the effect of different types of physical training on gymnastics jump height under the meta-analysis methodology. The PRISMA guidelines were followed. The electronic databases used in the search were EBSCOhost (SPORTDiscus, MEDLINE, Academic Search Complete, E-Journals, OmniFile Full Text Select (HW Wilson), Web of Science, Scopus, SciencDirect, Research Gate, and Pubmed in order to identify relevant articles regarding the use of physical training and the assessment of jump height in gymnasts before and after intervention. Based on the inclusion criteria, 29 individual studies and 157 individual effect sizes (TE) were coded. The total sample included 688 gymnasts. The overall TE of the experimental group was low to moderate and significant (TE = 0.33, . < 0.001*). A significant difference was evidenced (p = 0.001*) between the types of training. The Post Hoc analysis showed that the global TE of plyometrics training (TE = 0.85, . < 0.001*) was higher than that of stretching (TE = -0.07, . = 0.56) and "others" (TE = 0.48, . < 0.001*), but not than vibration (TE = 0.54, . < 0.001*). Furthermore, the overall TE of stretching was significantly lower than all the other types of training. It was concluded that the type of training with the highest overall TE was plyometrics, followed by vibrational platform training. Stretching does not appear to be significantly related to gymnastics jump height.

Resumo Ulloa-Sánchez, P., e Hernández Elizondo, J. (2021). Efeito de diferentes tipos de treinamento físico na altura do salto de ginastas: metanálise. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(1), 1-35. Este estudo teve como principal objetivo determinar o efeito de diferentes tipos de treinamento físico na altura de salto de ginastas, por meio da metodologia de metanálise. Foram seguidas as diretrizes do PRISMA e consultadas, na busca, as bases de dados eletrônicas: EBSCOhost (SPORTDiscus, MEDLINE, Academic Search Complete, E-Journals, OmniFile Full Text Select (HW Wilson), Web of Science, Scopus, SciencDirect, Research Gate e Pubmed, para identificar artigos relevantes que investigaram a aplicação de um treinamento físico e avaliaram a altura do salto em ginastas antes e depois da intervenção. Após o processo de seleção dos estudos e com base nos critérios de inclusão, foram codificados 29 estudos individuais e 157 tamanhos do efeito (TE) individuais. A amostra total de sujeitos foi de 688 ginastas. O grupo experimental apresentou um TE global de baixo a moderado e significativo (TE = 0,33, . < 0,001*). Diferença significativa (. = 0,001*) entre os tipos de treinamento; a análise Post Hoc mostrou que o TE global do treinamento de pliometria (TE = 0,85, . < 0,001*) foi maior do que o do alongamento (TE = -0,07, p = 0,56) e "outros" (TE = 0,48, . < 0,001 *), mas não maior do que o de vibração (TE = 0,54, . < 0,001 *); além disso, o TE global de tipo de alongamento foi significativamente menor do que todos os tipos de treinamento. Concluiu-se, portanto, que o tipo de treinamento que apresentou o maior TE geral foi o de pliometria, seguida do treinamento em plataforma vibracional. O alongamento não parece estar significativamente relacionado à altura de salto de ginastas.

Reliability and sensitivity of countermovement jump-derived variables in detecting different fatigue levels / Reprodutibilidade e sensibilidade das variáveis derivadas do salto com contra movimento na detecção de diferentes níveis de fadiga

ABSTRACT The aim was to verify the reliability and sensitivity of countermovement jump (CMJ) derived variables in detecting small, moderate and large changes and whether the capacity of CMJ-derived variables in detecting fatigue is dependent of the volume of the fatiguing exercise. Seventeen physically active men performed two fatigue protocols, on separate weeks, composed by continuous vertical jumps: short protocol (7 x 10 jumps) and long protocol (14 x 10 jumps). Jump height (JH), power output (PO), impulse (IMP) and vertical stiffness (KVERT) were measured during CMJ prior to and immediately after the fatigue protocols. Intraclass coefficient correlation, typical error, smallest worthwhile change and magnitude-based inference were analyzed. PO and JH presented excellent reliability and good sensitivity to detect small and medium changes, respectively. Negative effects of fatigue could be detected most likely by PO, regardless of fatiguing exercise volume. JH and IMP seem to be affected only after long protocol and KVERT only after short protocol. In conclusion, PO (peak and mean) is the better marker in CMJ with excellent reliability and sensibility, which allows detect even the small effects and differentiate the fatigue levels.

RESUMO O objetivo foi verificar a reprodutibilidade e a sensibilidade de variáveis derivadas do salto com contra movimento (CMJ) na detecção de pequenas, moderadas e grandes alterações e se a capacidade das variáveis em detectar fadiga é dependente do volume do exercício fatigante. Dezessete homens fisicamente ativos realizaram dois protocolos de fadiga, em semanas separadas, compostos por saltos verticais contínuos: protocolo curto (7 x 10 saltos) e protocolo longo (14 x 10 saltos). A altura do salto (JH), a potência (PO), o impulso (IMP) e a rigidez vertical (KVERT) foram mensurados durante o CMJ antes e imediatamente após os protocolos de fadiga. Foram avaliados o coeficiente de correlação intraclasse, erro típico de medida, mínima mudança valiosa e magnitude baseada em inferência. PO e JH apresentaram excelente reprodutibilidade e boa sensibilidade para detectar pequenas e médias alterações, respectivamente. Os efeitos da fadiga podem ser detectados mais provavelmente pela PO, independentemente do volume de exercício fatigante. JH e IMP parecem ser afetados somente após protocolo longo e KVERT somente após protocolo curto. Em conclusão, PO (pico e média) é o um marcador melhor durante o CMJ com excelente reprodutibilidade e sensibilidade, o que permite detectar até mesmo pequenos efeitos e diferenciar níveis de fadiga.

Effects of Plyometric Training on Explosive and Endurance Performance at Sea Level and at High Altitude.

Plyometric training performed at sea level enhance explosive and endurance performance at sea level. However, its effects on explosive and endurance performance at high altitude had not been studied. Therefore, the aim of this study was to determine the effects of a sea level short-term (i.e., 4-week) plyometric training program on explosive and endurance performance at sea level and at high altitude (i.e., 3,270 m above sea level). Participants were randomly assigned to a control group (n = 12) and a plyometric training group (n = 11). Neuromuscular (reactive strength index - RSI) and endurance (2-km time-trial; running economy [RE]; maximal oxygen uptake - VO2max) measurements were performed at sea level before, at sea level after intervention (SL +4 week), and at high altitude 24-h post SL +4 week. The ANOVA revealed that at SL +4 week the VO2max was not significantly changed in any group, although RE, RSI and 2-km time trial were significantly (p < 0.05) improved in the plyometric training group. After training, when both groups were exposed to high altitude, participants from the plyometric training group showed a greater RSI (p < 0.05) and were able to maintain their 2-km time trial (11.3 ± 0.5 min vs. 10.7 ± 0.6 min) compared to their pre-training sea level performance. In contrast, the control group showed no improvement in RSI, with a worse 2-km time trial performance (10.3 ± 0.8 min vs. 9.02 ± 0.64 min; p < 0.05; ES = 0.13). Moreover, after training, both at sea level and at high altitude the plyometric training group demonstrated a greater (p < 0.05) RSI and 2-km time trial performance compared to the control group. The oxygen saturation was significantly decreased after acute exposure to high altitude in the two groups (p < 0.05). These results confirm the beneficial effects of sea level short-term plyometric training on explosive and endurance performance at sea level. Moreover, current results indicates that plyometric training may also be of value for endurance athletes performing after an acute exposure to high altitude.