Factors correlated with volleyball spike velocity.

BACKGROUND: Spike effectiveness represents a determining element in volleyball. To compete at a high level, the player must, in particular, produce a spike characterized by a high ball velocity. HYPOTHESIS: Some muscular and physical features could influence ball velocity during the volleyball spike. STUDY DESIGN: Descriptive laboratory study. METHODS: A total of 19 male volleyball players from the 2 highest Belgian national divisions underwent an isokinetic assessment of the dominant shoulder and elbow. Ball velocity performance (radar gun) during a spike test, morphological feature, and jump capacity (ergo jump) of the player were measured. We tested the relationship between the isokinetic parameters or physical features and field performances represented by spike velocity. We also compared first-division and second-division player data. RESULTS: Spike velocity correlated significantly with strength performance of the dominant shoulder (internal rotators) and of the dominant elbow (flexors and extensors) in the concentric mode. Negative correlations were established with the concentric external rotator on internal rotator ratio at 400 deg/s and with the mixed ratio (external rotator at 60 deg/s in the eccentric mode on internal rotator at 240 deg/s in the concentric mode). Positive correlations appeared with both the volleyball players' jump capacity and body mass index. First-division players differed from second-division players by higher ball velocity and increased jump capacity. CONCLUSION: Some specific strength and physical characteristics correlated significantly with spike performance in high-level volleyball practice. CLINICAL RELEVANCE: Our results could provide useful information for training management and propose some reflections on injury prevention

Shoulder terminal range eccentric antagonist/concentric agonist strength ratios in overhead athletes

Objective: The agonist-antagonist strength relationship for shoulder external rotation and internal rotation was formerly described by the relatively more functional ratios of eccentric external rotator to concentric internal rotator moments, and eccentric internal rotator to concentric external rotator moments for the entire range of motion. The aim of this study was to provide descriptive data for terminal range eccentric antagonist/concentric agonist rotator cuff strength in overhead athletes. Methods: The dominant and non-dominant shoulders of 40 asymptomatic military overhead athletes were tested through a range of 20 degrees of external rotation to 90 degrees of internal rotation using the Cybex NORM isokinetic dynamometer at a speed of 90 degrees/s. Differences between the dominant and non-dominant shoulders were assessed using the paired samples t-test. Results: The terminal range ratios during external rotation (20 degrees of internal rotation -10 degrees of external rotation) were found to be 2.09 and 1.58 for the dominant and non-dominant shoulders, respectively, whereas the terminal range ratios during internal rotation (60-90 degrees of internal rotation) were 1.03 and 1.19 for the dominant and non-dominant shoulders, respectively. These ratio differences between the dominant and non-dominant shoulders were significant (P < 0.01 for external and internal rotation). Conclusion: The muscle torque ratios of eccentric antagonist/concentric agonist are different between dominant and non-dominant shoulders of skilled overhead athletes at terminal ranges. This functional assessment of strength testing that reflects dynamic shoulder joint stability during the throwing activity at these specific ranges may provide valuable information either during preventive exercise programs or in the evaluation of the injured shoulder of the overhead athlete. We recommended functional exercises that improve eccentric external rotation strength on the dominant shoulder during the rehabilitation and prevention programs in overhead athletes

Consumo alimentar e perfil antropométrico de tenistas amadores e profissionais Food intake and anthropometric profile of amateur and professionals tennis players

INTRODUÇÃO: O perfil antropométrico e o consumo alimentar exercem grande influência no desempenho esportivo; entretanto, essas informações sobre tenistas brasileiros ainda são escassas. OBJETIVO: Descrever e comparar o consumo alimentar e o perfil antropométrico de tenistas amadores (AM) e profissionais (PRO). MÉTODOS: Foram avaliados 24 tenistas, com a seguinte distribuição: profissionais (PRO; n = 9) e amadores (AM; n = 15). Os atletas foram avaliados quanto a variáveis antropométricas (peso, estatura, circunferências e dobras cutâneas) e a composição corporal foi estimada por três diferentes protocolos. As dietas foram avaliadas a partir de três diários alimentares. RESULTADOS: Não houve diferença significativa no perfil antropométrico dos atletas PRO em relação aos AM (peso: 69,5 ± 9,8kg e 66,0 ± 5,0kg; estatura: 177,9 ± 4,3cm e 175,6 ± 2,7cm, IMC: 23,5 ± 1,4kg/m² e 22,6 ± 0,8kg/m² e gordura corporal: 13,0 ± 5,5% e 13,7 ± 2,4%, respectivamente). Observou-se significativo déficit energético entre a estimativa da necessidade energética e a ingestão energética relatada. O consumo de carboidratos apresentou-se no limite mínimo sugerido (AM: 6,3 ± 0,5g/kg/dia e PRO: 6,5 ± 0,7g/kg/dia), enquanto a ingestão de proteínas mostrou-se superior às recomendações disponíveis na literatura (AM: 2,4 ± 0,2g/kg/dia e PRO: 2,3 ± 0,3g/kg/dia). Com relação aos minerais, a principal preocupação foi a baixa ingestão de cálcio (AM: 798,1 ± 786,3mg/dia e PRO: 766,9 ± 602,4mg/dia). CONCLUSÃO: Não foram observadas diferenças significativas no perfil antropométrico e no consumo alimentar entre os atletas AM e PRO. Os desvios observados no consumo alimentar reforçam a necessidade de orientação/planejamento nutricional, a fim de atender às demandas específicas da modalidade, visando maximizar o desempenho.<br>The anthropometric profile and food intake play a key role in sports performance; however, there is little information available regarding Brazilian tennis players. AIM: the present study aimed to evaluate the food intake and the anthropometric profile of professional and amateur tennis players. METHODS: twenty-four tennis players were distributed in two groups: professionals (PRO; n = 9) and amateurs (AM; n = 15). The athletes were evaluated on their anthropometric measurements (body weight, height, circumferences and skin folders). Body fat was estimated from three different equations. Food intake was determined by a 3-day food diary. RESULTS: there were no significant differences from anthropometric profile between PRO and AM (body weight: 69.5 ± 9.8 kg and 66.0 ± 5.0 kg; height: 177.9 ± 4.3 cm and 175.6 ± 2.7 cm, BMI: 23.5 ± 1.4 kg/m² and 22.6 ± 0.8 kg/m² and body fat: 13.0 ± 5.5% and 13.7 ± 2.4%, respectively). Significant difference between the energy expenditure and estimation and reported energy intake was observed. Both groups showed low carbohydrate (AM: 6.3 ± 0.5 g/kg/day and PRO: 6.5 ± 0.7 g/kg/day) and high protein intake AM: 2.4 ± 0.2 g/kg/day and PRO: 2.3 ± 0.3 g/kg/day) compared to the current recommendations. Very low calcium intake was observed (AM: 798.1 ± 786.3 mg/day and PRO: 766.9 ± 602.4 mg/day). CONCLUSION: no significant differences were detected for food intake pattern and anthropometric profile between PRO and AM. The results presented herein reinforce the relevance of nutritional planning in order to achieve specific demands of tennis and maximize performance