Universidade Federal do Rio Grande do Sul - UFRGS, Porto Alegre, Brazil.
Published: April 2024
AI Article Synopsis
Article Abstract
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 ( < .001), U18 ( < .001), U19 ( < .001), and U21 ( = .04). Regarding vertical jump performance, U18 athletes born in Q2 reached higher spike jump heights ( = .006) and block jump heights ( = .002) than athletes born in Q4, and U19 athletes born in Q1 reached higher block jump heights than athletes born in Q3 ( = .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.
Harry, JR, Park, S, Stewart, M, Hite, M, Simms, A, Larsen, M, and Bishop, C. Asymmetry during landing impacts following jumps with aerial rotation in collegiate men's basketball players. J Strength Cond Res XX(X): 000-000, 2024-This project explored whether (a) landing performances and (b) impact force asymmetries were different during countermovement jump (CMJ) landings with leftward versus rightward aerial rotation in 19 collegiate men's basketball players.
Objectives: Early specialization in a single sport from childhood is associated with an increased risk for acute and overuse injuries. Conversely, experience in multiple sports may be associated with improved neuromuscular control and performance. Currently, early sports specialization remains poorly researched in Japan.
The aim of this study was to examine the influence of three warm-up protocols, with and without post-activation performance enhancement (PAPE), on sprint and vertical jump performance in female athletes. Twenty-five university futsal athletes were randomly assigned to three protocols: i) Traditional Warm-Up (TWU), involving cardiovascular, coordination exercises, and dynamic stretching; ii) Drop Jump Warm-Up (DJWU), consisting of drop jumps from heights of 30 and 40 cm; and iii) Maximum Isometric Warm-Up (MIWU), with high-intensity isometric contractions held for 10 seconds in a squat position at approximately 130-135 degrees of knee flexion. Tests included the countermovement vertical jump (CMVJ) and a 20-meter sprint (S20).
The primary inquiry of this study was to determine if exergaming is more effective than balance training in improving dynamic postural control during jump-landing movements among athletes with chronic ankle instability (CAI). Additionally, the study aimed to compare the effectiveness of these interventions on clinical and psychological outcomes. This study was a randomized, single-blinded, controlled trial in which participants were assigned to either an exergaming group or a balance training group.
Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Physical Therapy Center, National Cheng Kung University Hospital, Tainan, Taiwan. Electronic address:
This study aimed to investigate the hamstring activation in athletes with hamstring strain injuries in vertical jump tasks using an EMG time-frequency analysis. Fifteen injured athletes and 15 matched controls were recruited. The EMG signals of the lateral hamstring (LH) and medial hamstring (MH) were assessed during countermovement, squat, and drop vertical jump tasks.
