A análise das ações de jogo no Voleibol de elite: um estudo comparativo

2026-07-27T15:00:52Z

Title: A análise das ações de jogo no Voleibol de elite: um estudo comparativo Authors: Arezes, Gonçalo; Lima, Ricardo Abstract: Foi objetivo deste estudo analisar as ações de jogo de atletas de elite participantes no Campeonato da Europa de Voleibol Masculino 2023. Para isso, durante a fase de grupos, analisou-se as equipas do Grupo D, constituído por França, Roménia, Grécia, Portugal, Turquia e Israel, o que perfez um total de 30 jogos, 84 atletas analisados (12 distribuidores, 12 opostos, 24 centrais, 24 de rede e 11 líberos) e 1176 ações observadas. Optou-se pela comparação de médias superior a duas variáveis independentes, através da ANOVA (post-hoc de t-Tukey) para identificar as diferenças significativas entre variáveis independentes. Para calcular o tamanho do efeito, foi utilizado o método de Cohen (d) (d <0.2 trivial; 0.2

Assessment of energy availability in a professional female soccer team

2026-05-18T15:00:56Z

Title: Assessment of energy availability in a professional female soccer team Authors: Oliveira, César Chaves; Leão, César; Mendes, António Pedro; Custódio, Catarina; Ng, Mafalda; Ribeiro, Nuno; Loureiro, Nuno; Araújo, João Pedro; Afonso, José; Tavares, Francisco; Rocha-Rodrigues, Sílvia Abstract: Relative Energy Deficiency in Sport is often observed in athletes, especially women, and can negatively affect exercise performance by reducing power output, recovery capacity, neuromuscular function, and/or increasing injury risk. Purpose: we aimed to evaluate the energy availability (EA) of female football players from the highest Female Football Portuguese League across a typical in-season microcycle. Methods: from a professional female football club competing in the highest Female Football Portuguese League, 14 players completed the study (mean ± SD, 22.50 ± 4.38y, 57.23 ± 8.61 kg, 164 ± 6.00 cm, 18.33 ± 2.48 % of body fat and 46.34 ± 6.05 kg of fat-free mass). Participants played for 4.79 ± 4.47 years at a professional level. The load was monitored using a portable 18-Hz global positioning system (GPS) device for 7 consecutive days during a typical mid-season microcycle (one match day (MD), 4 training sessions and 2 rest days). To assess energy intake (EI), the 7-day dietary food recording method was used. Exercise energy expenditure (EEE) was estimated applying the proper METs for their exercise activities and corrected for the resting metabolic rate. The EA (kcal/kg fat-free mass/day) was estimated by using the following equation: (EI-EEE)/fat-free mass. Players with values <30 were classified as low EA, [30 - 44] as reduced EA and ≥ 45 as optimal EA. Results: energy intake for rest days, training days and MD was 1661.52 ± 584.45, 1719.30 ± 441.25 and 2125.07 ± 348.60 kcal/day, respectively, with significant differences between rest days and MD (p = 0.045; ES = 1.02). The EEE for training days was lower than MD (545.16 ± 164.50 vs. 703.90 ± 297.57 kcal/day; p = 0.045; ES = 0.66). The EA for training days was lower than rest days (56.78 ± 15.24 vs. 26.31 ± 13.15; p = 0.04; ES = 2.14) and MD (37.77 ± 11.49 vs. 26.31 ± 13.15; p = 0.017; ES = 0.96), representing a large effect. According to the EA classification, rest days and MD were characterized mainly by a reduced EA while training days were low EA. Conclusions: reduced or low EA is prevalent among players of the highest Female Football Portuguese League, during a typical mid-season microcycle. As an adequate energetic intake is critical for maximal exercise performance, recovery, and health, athlete screening and proper nutritional intervention when needed is strongly advised.

Is there a relationship between birth quartile and vertical jump performance among young male elite volleyball athletes?

2026-04-07T14:44:40Z

Title: Is there a relationship between birth quartile and vertical jump performance among young male elite volleyball athletes? Authors: Castro, Henrique de Oliveira; Lima, Ricardo; Figueiredo, Lucas Savassi; De Oliveira, Vivian; Peyré-Tartaruga, Leonardo Alexandre; Kruel, Luiz Fernando Martins; Laporta, Lorenzo Iop; Costa, Gustavo De Conti Teixeira; Berriel, Guilherme Pereira 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 (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, andU19athletesborn inQ1reached 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.

Hip muscle strength ratios predicting groin injury in male soccer players using machine learning and multivariate analysis — a prospective cohort study

2025-01-14T15:43:57Z

Title: Hip muscle strength ratios predicting groin injury in male soccer players using machine learning and multivariate analysis — a prospective cohort study Authors: Kekelekis, Afxentios; Musa, Rabiu Muazu; Nikolaidis, Pantelis T.; Clemente, Filipe Manuel; Kellis, Eleftherios Abstract: Despite ongoing efforts, the relationship between groin strength and injury remains unclear. The challenge of accurately predicting injuries presents an opportunity for researchers to develop prevention strategies to reduce the occurrence of such injuries. Consequently, this issue requires further investigation to obtain insights into effective mitigation strategies. In 120 male soccer players, the maximum isometric strength of the hip muscle groups was measured, and the strength ratios were calculated. Previous injury and anthropometric data were registered. Injury data were collected following the FIFA/UEFA consensus. k-nearest neighbor (k-NN) was used to predict the incidence of injury, while the significant predictive variables of the k-NN algorithm were fitted into a multivariate logistic regression model (LR) to analyze the likelihood of players sustaining a groin injury. The LR model determined two variables as significant predictors of groin injury. Players were less likely to sustain a groin injury by 76% for each decrease of the adductor/abductor isometric strength ratio in the non-dominant limb (OR = 0.238, CI 95% = [(0.098–0.572]). Players with a history of previous injury had a 67% greater risk of sustaining an injury (OR = 0.333, CI 95% = [(0.1068–1.038]). Isometric hip adductor and abductor strength imbalances of the non-dominant lower limb and a history of previous injury were risk factors for groin injury in soccer players.

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A análise das ações de jogo no Voleibol de elite: um estudo comparativo

Assessment of energy availability in a professional female soccer team

Is there a relationship between birth quartile and vertical jump performance among young male elite volleyball athletes?

Hip muscle strength ratios predicting groin injury in male soccer players using machine learning and multivariate analysis — a prospective cohort study