Avaliação muscular isocinética da articulação do joelho em atletas das seleções brasileiras infanto e juvenil de voleibol masculino

Abstract

The vertical jump is a basic volleyball practice that demands a high ability to generate strength and work in the muscles involved, mainly in the quadriceps muscle. Due to such demand, muscle imbalances between extensor and flexor muscles may be present, causing an overloading on the muscle-tendinous structures of the knee joint. Thus, the establishment of normal parameters for the muscle function related to that joint in volleyball athletes is necessary. Therefore, the purpose of this study was to assess through isokinetic dynamometry the peak torque, work peak, agonist/antagonist ratio, and fatigue index of the flexor and extensor of the knee among both volleyball athlete population. The isokinetic flexion and extension tests of the knees were performed in the concentric-concentric seat mode at 60 and 300 o /sec. velocity in thirtysix athletes (20 under 19-under 21, and 16 under 21). The data allowed to set the parameters for the muscle function of the knee joint among athletes of the 2003 Under 19-Under 21 and Under 21 Brazilian National Team Selection of Male Volleyball. Athletes presented peak torque and work peak values normalized by the body mass to the upper quadriceps to the mean normal values for the athletes and non-athletes populations. Compared to other categories, the under 21 athletes presented significantly higher values for the agonist/antagonist ratio, and peak work ratio of the knee flexors at 60 o /sec. velocity. Furthermore, the agonist/antagonist ratio was lower than the reference value expected for both categories, thus characterizing predominance in the extensor musculature over the flexor musculature. The fatigue index was close to what would be expected for the majority of athletes. The present study may be useful as comparison basis for future studies aiming evaluate the isokinetic muscle function in volleyball players.

The trunk extensor flexor relationship in men and women by isokinetic dynamometry

“…This has led to difficulty in discussing this study directly with the literature. (8,10) The study sample showed homogeneous in age and BMI as shown in Table 1. Regarding the number of participants was statistically significant, since the average found in the literature on the subject was 30-40 participants.…”

“…(8) The relationship between muscle groups agonists/antagonists can be used to verify imbalances and weaknesses in certain muscle groups that may predispose the subject to injury. (9,7,10) Electromechanical dynamometers allow measurement of parameters such as torque production capacity, muscle power, fatigue and ability to generate work for several musculature. The data obtained from the use of these dynamometers have had major impact on clinical decision-making.…”

Efeito do FIFA11+ e do treinamento convencional de handebol sobre força isocinética e equilíbrio

“…Before starting the test, athletes performed a five-minute warm-up on an exercise bike and three submaximal repetitions prior to familiarization with procedures 11 . Then, they performed five maximal repetitions of knee flexion and extension in the concentric-concentric mode at speed of 60°/s, in which they received verbal stimulation to develop maximum strength at each repetition 11 . It was chosen in the present study by the concentric form, because it is safer and of easier understanding for the athlete's execution 12 .…”

Análise isocinética da articulação do cotovelo em crianças com paralisia cerebral

“…Por outro lado, o dinamômetro isocinético permite a avaliação da ação muscular no desempenho de movimentos monoarticulares em várias velocidades, mensurando o torque, trabalho e a relação líquida dos músculos agonista/antagonista 56 (BITTENCOURT et al, 2005) …”