RESUMO Lesões articulares no ombro são bastante comuns em atletas de voleibol. Estudos sugerem que o desequilíbrio muscular entre os músculos rotadores internos e externos do ombro podem estar relacionados a tais lesões. O objetivo deste estudo foi comparar os picos de torque (PT) concêntricos de rotadores externos e internos do ombro em jogadores de voleibol com (HL) e sem histórico (SH). Participaram 21 jogadores de voleibol do sexo masculino (idade: 17,2±1,96 anos; estatura: 183,6±6,63 cm; peso: 75,1±11,50 kg; gordura: 13,4±2,77%) divididos em 2 grupos: HL (n=8); SH (n=13). Foram realizadas duas séries de 5 repetições concêntricas de rotação interna (RI) e externa (RE) do ombro nas velocidades de 60 e 180°·s para posterior cálculo das razões convencionais. O PT concêntrico para RE em ambas velocidades avaliadas (60 e 180°·s) foram significativamente superiores para o grupo HL. O PT concêntrico na RI foi maior comparado a RE em ambos os grupos. Apenas a razão convencional à 60º/s, foi significativamente maior para jogadores HL. Conclui-se que os atletas com histórico de lesão de ombro apresentam desequilíbrio muscular, podendo este fator ser considerado um aspecto que tenha levado ao aparecimento do evento lesivo.

ABSTRACT Joint shoulder injuries are quite common in volleyball athletes. Studies suggest that muscle imbalance between the internal and external rotator muscles of the shoulder may be related to such lesions. The objective of this study was to compare the concentric torque peaks (PT) of external and internal rotators of the shoulder in volleyball players with (HL) and without history of injuries in joint shoulder (SH). Participated of present study 21 male volleyball players (age: 17.2 ± 1.96 years, height: 183.6 ± 6.63 cm, weight: 75.1 ± 11.50 kg, fat: 13.4 ± 2, 77%) divided into 2 groups: HL (n = 8); SH (n = 13). Two series of 5 maximal concentric repetitions of internal (RI) and external rotation (RE) of the shoulder were performed at speeds of 60 and 180 °·s for later calculation of the conventional ratio PT concentric for RE at both velocities evaluated (60 and 180 °·s) were significantly higher for the HL group. PT concentric in RI was higher compared to RE in both groups. Only the conventional rate at 60°·s was significantly higher for HL players. It is concluded that athletes with a history of shoulder injury present muscular imbalance, and this factor can be considered an aspect that has led to the appearance of the injury event.

The aim of this study was to analyze the effect of different squat depths in the performance and biomechanical parameters at counter movement jump (CMJ). Twenty-two male volleyball or basketball players volunteered to participate in this study and all were currently competing at the college level. The CMJ was performed in three different conditions: 1) with relative knee flexion at the end of counter movement phase smaller than 90° (<90°); 2) greater than 90° (>90°), and; 3) preferred position (PREF). During the CMJ, kinematic, kinetic, and electromyography parameters were assessed. ANOVA for repeated measures with post-hoc Bonferroni´s test was used for variables comparison, with a significance level set at p≤0.05. The higher performance was on PREF and <90° situations compared with CMJ>90°. Average and peak power, as well as absolute and normalized peak forces, were higher in >90° CMJ. The peak velocity of CG and angular velocities of hip and knee were higher in the <90° condition. EMG activity of the vastus lateralis (VL) during the descending and ascending phases were higher in position >90°. Recuts femoris and biceps femoris did not show difference in any jump phases. In conclusion, the knee flexion interferes the performance and the biomechanical variables at the CMJ. The highest jumps were got at a deeper squat, so this technique could be used for athletes in order to optimize the vertical jump performance in the training and competitions.

O objetivo do presente estudo foi comparar as características antropométricas e aptidão aeróbia e anaeróbia entre ciclistas e triatletas competitivos. Participaram do estudo 11 ciclistas e 12 triatletas com experiência em competições esportivas. As avaliações foram realizadas em dois dias distintos, com intervalo de 48 h entre as sessões. No primeiro dia, foram realizados a avaliação antropométrica (massa corporal, estatura e dobras cutâneas) e um teste incremental máximo para determinação do consumo máximo de oxigênio, potência máxima, frequência cardíaca máxima, lactato máximo, primeiro limiar de lactato (LL1) e segundo limiar de lactato (LL2). No segundo dia, foi realizado um teste de Wingate para obter a potência pico, potência média e índice de fadiga. Houve diferença significativa (p < 0,05) e com tamanho de efeito moderado (0,80 - 1,5) para a dobra cutânea da coxa média (15,2 ± 6,3 e 10,5 ± 4,8 mm), potência no LL1 (195,0 ± 30,9 e 162,7 ± 28,3 W), potência no LL2 (247,6 ± 25 e 219,7 ± 37,9 W) e índice de fadiga (47,2 ± 13,0 e 60,1 ± 16,4 %) entre ciclistas e triatletas, respectivamente. As demais variáveis analisadas não diferiram estatisticamente entre os grupos. Os triatletas e ciclistas são semelhantes em relação às características antropométricas. No entanto, ciclistas apresentam maiores valores de potência nos limiares (LL1 e LL2) e menores valores do índice de fadiga.

The aim of this study was to compare anthropometric characteristics and aerobic and anaerobic fitness between competitive cyclists and triathletes. The sample consisted of 11 cyclists and 12 triathletes with experience in competitions. The tests were performed on two different days, with an interval of 48 h between sessions. On the first day, the athletes were submitted to anthropometric assessment (body mass, height, and skinfold thickness) and a maximal incremental test to determine maximal oxygen uptake, maximum power, maximum heart rate, maximum lactate, and the first (LL1) and second lactate threshold (LL2). The Wingate test was conducted on the second day to determine peak power, average power, and fatigue index. There were significant difference (p < 0.05), with medium effect size (0.80 - 1.5), in mid-thigh skinfold thickness (15.2 ± 6.3 and 10.5 ± 4.8 mm), power at LL1 (195.0 ± 30.9 and 162.7 ± 28.3 W), power at LL2 (247.6 ± 25.0 and 219.7 ± 37.9 W), and fatigue index (47.2 ± 13.0 and 60.1 ± 16.4%) between cyclists and triathletes, respectively. The other variables did not differ between groups. Anthropometric characteristics are similar in triathletes and cyclists. However, cyclists present higher power outputs at the lactate thresholds (LL1 and LL2) and lower fatigue indexes.

A exposição aguda à altitude sem aclimatação prévia pode provocar mal-estar e diminuir o desempenho físico e esportivo. O objetivo deste estudo foi verificar o efeito de sessões de hipoxia normobárica, em repouso, na Frequência Cardíaca (FC) e Saturação de Oxigênio da Hemoglobina (SpO2) em atletas de futebol profissional. Participaram do estudo 13 atletas, os quais foram submetidos a 15 sessões de hipoxia, 5-6 vezes por semana. A duração das sessões foi de 60 min, com fração inspirada de oxigênio entre 14% e 12 %. A SpO2 e FC foram registrados segundo a segundo durante a primeira e última sessão. Para comparar, a SpO2 e FC da primeira sessão, última sessão e normoxia foi utilizado Anova para medidas repetidas. Houve aumento da SpO2 (p<0,05) e redução da FC (p<0,05) na última sessão, quando comparado à primeira. Concluímos que o protocolo de treinamento utilizado no estudo melhora a resposta do organismo em hipoxia.

The acute exposure at altitude without previous acclimatization may cause sickness and decrease the sport and physical performance. This research aimed at verifying the effect of normobaric hypoxia sessions, at rest, on the Hemoglobin Oxygen Saturation (SpO2) and the Heart Rate (HR) of professional soccer athletes. Thirteen athletes performed 15 sessions of hypoxia, 5-6 times a week, with 60 min of duration and with the fraction of inspired oxygen between 14 and 12%. The SpO2 and HR were recorded every second during the first and the last session. In order to compare the SpO2 and HR from the first session, last session and normoxia it was used the ANOVA with repeated measures. There was an increase in the SpO2 (p<0.05) and a decreased HR (p<0.05) for the last session when compared to the first session. We conclude that the training protocol used in the acclimatization study improves the organism response to hypoxia.